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UNDP/PAPPPALESTINE CONSTRUCTION OF THE KHAN YOUNIS Waste Water Treatment Plant

VOLUME 2 – PART 2 – TECHNICAL SPECIFICATIONS – CIVIL WORKS

PALESTINECONSTRUCTION OF THE KHAN YOUNIS

WASTE WATER TREATMENT PLANT

VOLUME 2 – TECHNICAL SPECIFICATIONS PART 2 – CIVIL WORKS

SOGREAH CONSULTANTS/UNIVERSAL GROUP N° 1310076 - MAY 23 VOLUME 2 – PART 2 - PAGE 1



TABLE OF CONTENTS

1. DESCRIPTION OF WORK..................................................................................32. MATERIALS AND WORKMANSHIP.................................................................53. EXCAVATION, TRENCHING AND BACKFILLING........................................94. MANHOLES AND CHAMBERS........................................................................195. CONCRETE WORKS..........................................................................................226. MASONRY WORKS............................................................................................347. PAINTING AND PROTECTIVE COATINGS...................................................378. METALWORK.....................................................................................................379. PROTECTIVE COATING, LINING And PAINT WORK.................................3810. STEEL PIPES, VALVES AND FITTINGS.....................................................4311. WELD INSPECTION AND TESTS.................................................................5012. HYDROSTATIC PRESSURE TEST................................................................5213. CONCRETE MANHOLES..............................................................................5314. FINISHING WORKS.......................................................................................5615. LANDSCAPING................................................................................................6616. BITUMINOUS CONSTRUCTION..................................................................7417. CONCRETE BLOCK PAVING........................................................................85




1.DESCRIPTION OF WORK

1.1 General Information

1.1.1 Location of SiteThe construction site for Khan Younis Waste Water Treatment Plant is located at eastern side of Khan Younis governorate beside Sofa crossing point.

1.1.2 Adjoining ContractsThis contract is one of four contracts to be implemented separately under the ” Phase I, Khan Younis Wastewater Treatment Plant ”. These contracts are1- Construction of Khan Younis Waste Water Treatment Plant (KY WWTP), 2- Construction of main pressure lines to the sea, and to the infiltration basins,3- Construction of the infiltration basins in Al Fukhari, and4- Construction of the electrical power supply to the WWTP.

1.1.3 Temporary WorksThe Contractor shall take into consideration all temporary works he may require for the execution of the Works. He shall submit four (4) weeks in advance of any scheduled temporary work, detailed drawings and supporting calculations on stability, hydraulics or any other calculation considered essential by the Engineer’s Representative.Within two weeks after submission of the afore-mentioned drawings and calculations the Engineer’s Representative shall comment or approve the relevant Temporary Works.

Notwithstanding the approval by the Engineer’s Representative of any temporary works, the Contractor shall remain responsible for their efficiency, safety and maintenance, and for all obligations in regards to such works specified or implied in the Contract until the removal of such works.Unless provided for in the Bill of Quantities, expenditures whatsoever dealing with any temporary works shall be deemed to be covered by the other rates and prices in the Bill of Quantities and shall not be measured for payment nor be paid for under a separate item.

1.1.4 Demolish And Dismantling WorksThe Engineer’s Representative must be given at least two weeks notice in writing before demolition or dismantling of any existing obstruction on site or relocation of utilities. The Contractor shall require the approval of the Engineer’s Representative for the method and order of work and the steps taken to ensure the safety and stability of any remaining structures affected thereby. This approval by the Engineer’s Representative shall not in any way relieve the Contractor of his responsibilities in connection with carrying out the Works.

The Contractor shall dismantle carefully and handing over to the store or any place as directed by the Engineer’s Representative all the items specified in the Bill of Quantities.

No measurement will be required for this type of work, unless it is clearly specified in the Bill of Quantities. No payment shall be made for clearing, grubbing, demolition, dismantling, or relocation of utilities, unless it is clearly specified in the Bill of Quantities. Otherwise prices shall be deemed to be included in the various unit prices of the items of the Contract.

The average yearly rainfall in the eastern part of Khan Younis governorate is 200 mm which falls during the months of October to March. Rainfall intensities can very occasionally exceed 100 mm per hour, and when this happens flooding occurs in low lying areas.

1.1.5 Datum LevelAll levels (z co-ordinates) are referred to Mean Sea Level (MSL), which is (00.00).The Contractor shall establish his own additional bench marks and control points needed under the Contract, all levels and coordinates on new control points shall be based on the level and coordinates of the main bench mark that will be handed to the contractor at the commencement of work by the Consultant.




1.1.6 Co-ordinate SystemThe official grid system for Gaza is defined as the Palestinian Co-ordinate System.

1.1.7 Local MaterialCement and reinforcement steel are imported from Israel and outside. Sources of supply of sand are from Palestinian Territory. Sources of supply aggregates from West Bank via Israel and from Israel itself. The Contractor shall make his own investigations to secure the necessary supply of cement locally or imported and of aggregates for his operations during the full construction period. Mechanical parts, pumps, pipes and electrical equipment will most likely have to be imported. The contractor shall set all precautions to avoid delays of supply due to the frequent closure of the border to Israel.

1.2 Scope of WorksThe permanent works to be carried out within the scope of Construction of New Waste Water Treatment Plant facilities as shown in the contract drawings and in the BOQ and according to the relevant technical specifications.

1.3 Phasing Of Works And Time ScheduleThe Contractor shall on the basis of the indicated time schedule elaborate a detailed programme for the execution of the work given due consideration to his resources in plant and to his working methods. The programme shall show the interaction between activities and which activities are critical.The Contractor shall take into consideration that The construction work for the Infiltration Basins and the pressure line will be carried out by other contractor and during the same period of the construction of the New Waste Water Treatment Plant facilities.

1.4 Contractor’s AreaThe Contractor shall make his own arrangements with local authorities or private landowners for any areas needed for his plant, equipment, material etc.It is the Contractor’s responsibility to secure adequate supplies of water, sewerage disposal and electri-city for his needs from the local authorities or to make his own arrangements therefore.The Contractor shall also make his own arrangements for telecommunications.Irregularities in water and electricity supply may be expected to arise, therefore the Contractor may need to provide standby power and temporary water tanks in order to be able to carry out the Works in accordance with his contractual obligations.The Contractor shall make his own arrangements for collecting and disposing of sewage from his office and other facilities within the areas in his possessions to the satisfaction of the Engineer’s Representative.

1.5 Field Laboratory The Contractor may provide, set up and fully equip a field laboratory at the site. The laboratory shall be suitably located and of adequate size and layout to accommodate and operate all apparatus needed to carry out specified tests and to store samples, as required. All necessary personnel and labour required for the efficient running and maintenance of the laboratory and its equipment shall be provided by the Contractor. An indication of the equipment required is given under section 2 of Materials and Workmanship. Apart from necessary requirements to run the laboratory to the Engineer’s Representative’s satisfaction, the laboratory shall include a separate lockable office room, fully furnished for one site engineer from the Engineer’s Representative’s staff.If the contractor wishes not to provide a field laboratory as specified above, he may carry out specified tests at an independent laboratory approved by the Engineer’s Representative.




2.MATERIALS AND WORKMANSHIP

2.1 Standards And Codes Of PracticeThis Technical Specification is not complete in the respect of covering all materials and type of works occurring under this Contract. It shall be seen as complementation/clarifications and/or replacement of relevant standards where this is deemed necessary, for the materials and works it covers.If contradicting information between this Technical Specification and relevant standards should occur, this Technical Specification shall prevail unless otherwise directed by the Engineer’s Representative.For materials and works not covered by this Technical Specification, relevant standards shall apply.Depending on the origin of manufacture, materials complying with other well known standards will be accepted for incorporation in the works if deemed necessary by the Engineer’s Representative’s Representative, to be at least of equal quality as given by the specified standards. It is the objective, however, to standardize such installations and components that may eventually need replacement, to comply as far as possible with those already established in the Site.One original set of the latest issue of all reference standards shall be available on Site for the use of the Engineer’s Representative at the start-up of the Works. These standards shall remain the property of the Contractor when the work has been completed.Reference standards mentioned in the documents shall be regarded as minimum standards required. Where reference standards refer to other standards, code of practice etc., which are deemed to be necessary for execution of the Work, these standards, code of practice etc. shall also be handed over in original to the Engineer’s Representative’s Representative if so requested.The publication in effect on the date of issue of Contract Documents, except when a specific publication date is specified, shall be the standards in effect for execution of the Works.

2.2 Design DataWork, for which the Contractor shall or may be required to design, shall be designed in accordance with American National Standards Institute (ANSI), and American Society of Civil Engineers (ASCE).

2.3 Workmanship The Contractor shall employ only adult skilled labours and workmen according to Palestinian Laws and regulations, who have the good experience in such projects, as included in the General Conditions and Specifications. The Engineer’s Representative has the authority to dismiss any of the contractor’s labours or workmen; he found that he is not suitable to work in this particular project.

2.4 Laboratory and Testing Equipment

2.4.1 LaboratoryThe Contractor may choose to set up his own laboratory as indicated under 1.5 above. If he decides to do so, the laboratory shall be completed and operational at the commencement of the civil works.Furthermore, the laboratory building shall be supplied with electricity, water and air conditioning, and shall have a concrete floor capable of adequately supporting all testing equipment etc.

2.4.2 StaffingIf the Contractor chose to set up his own laboratory, he shall provide for the duration of the Contract:

an engineer or technician fully experienced in directing and undertaking site and laboratory tests using the specified or other necessary equipment, and in preparing appropriate reports on tests carried out, including all necessary computations involved;

a laboratory assistant, who has satisfactorily completed necessary education, capable of carrying out tests under the direction of the engineer or technician.

2.4.3 Testing EquipmentThe contractor shall perform all tests during the course of the Contract, as referred to in this Technical Specification in accordance with relevant Standard and Codes of Practice. The tests required in this Technical Specification mostly refer to American Society Testing and Material (ASTM). The




Contractor may propose to substitute such tests and test apparatus to similar test and test apparatus of other well known standards, subject to the approval of the Engineer’s Representative.Tests which shall be carried out frequently includes at least the following:

Soil and Aggregate tests:-dry density-compaction (CBR)-sieve analyses-water absorption-silt and clay content-sulphate content-chloride content-acid soluble content

Cement and Concrete Tests- cement setting time- water analysis- temperature- slump- water-cement ratio- cube, masonry block, paving block strength

Pipe Tests- pressure pipe testing equipment- gravity pipe testing equipment

2.4.4 Field EquipmentAt least the following equipment shall be provided exclusively for the supervision operations of the Engineer’s Representative:

automatic levelling instrument with two staffs, labelled with inch on one side and cm/mm on the other.

50 and 100 m tapes templates, spirit level required nos. of 2 m pocket tapes 3 m straight edge marking flags, ranging rods, stakes, paint etc., as required any additional equipment in normal site use, required by the Engineer’s Representative from

time to time. Furthermore, an electronic theodolite shall be available to the Engineer’s Representative

when required.

2.4.5 Lifting EquipmentThe Contractor’s lifting equipment shall, before use on site and as may be required during the construction period, be inspected according to the Standard regulations of relevant authorities in the Palestinian Territory.

2.5 Approvals

2.5.1 Approval of MaterialThe Contractor shall submit, for approval of the Engineer’s Representative, at least 21 days in advance of placing orders for any materials for incorporation in the Permanent Works, at least the following information:

name of manufacturer or supplier proposed; sufficient evidence to prove that the materials proposed comply in all respects with the

Specification and a declaration stating the Standards with which they comply; declaration that the materials will be supplied with the specified markings and certificates; manufacturer’s current instructions and explanatory data; details of fabrication and painting arrangements where appropriate;




declaration that the whole quantity required to complete the work can be supplied from the same source, with written evidence if requested.

Within 14 days of the receipt of the request from the Contractor, the Engineer’s Representative will return to the Contractor with his eventual approval, or request for further information. After such further information has been provided by the Contractor, the Engineer’s Representative will, again within 14 days, return to the Contractor with his reply. This procedure shall be repeated until final approval has been given by the Engineer’s Representative.Materials shall not be used in the Permanent Works until the Engineer’s Representative has given his written approval. Such approval shall not relieve the Contractor of his responsibility for the materials.

2.5.2 Inspection and Testing on the SiteAll materials delivered to the Site and workmanship on the Site shall be subject to inspection and testing by or under the direction of the Engineer’s Representative.

2.5.3 Tests on CompletionExcept where specifically agreed to the contrary in writing, the Contractor shall present all Plant and systems installed under the Contract for Tests on Completion, at least 14 days before the date for the Taking-Over Certificate for the Works. These tests are in addition to any works tests performed by the manufacturer and tests the Contractor may need to carry out in order to set up the systems to his own satisfaction.Before the Contractor offers Plant and systems for Tests Completion, all associated systems and installations are to be complete, checked, adjusted and set up. Final paintwork must be complete. Tests on Completion shall not be carried out until the approved operation and maintenance manuals have been provided.The Contractor shall submit to the Engineer’s Representative a detailed Schedule and Programme of Tests on Completion, to be agreed and completed 28 days before the commencement of testing.Testing shall be carried out in the presence of and to the satisfaction of the Engineer’s Representative and in the presence of one or more representatives of the Employer, to demonstrate that the Plant and systems perform in accordance with the Specification and are ready for operation. Undertaking of the tests and demonstrations shall be the responsibility of the Contractor and all costs associated therewith shall have been included in the rates and prices.The Contractor shall provide all rigs, test loads, instrumentation and labour assistance necessary for the proper performance of the Tests on Completion, and shall take and record such readings as are required.Any defects discovered during the Tests on Completion shall be recorded by the Contractor and Engineer’s Representative and shall be duly rectified by the Contractor. Following rectification the Contractor shall repeat the tests before final handover of the Plant or system.On completion of the Tests on Completion, the Contractor shall provide three copies of the Test Schedule completed for all observed tests and data readings. A Test Certificate shall be submitted in triplicate for signature by the Engineer’s Representative.

2.5.4 ManualsExcept where specifically agreed to the contrary in writing, the Contractor shall provide comprehensive manuals in English, with those to be used by operators for operation and maintenance translated to Arabic, covering all aspects of operation and maintenance in respect of all Plant and systems installed under the Contract. The Contractor shall submit the manuals in hard copies draft form at least 2 months before the date for the Tests on Completion. The Contractor shall make such modifications and additions as the Engineer’s Representative requires and shall re-submit the manuals for final approval by the Engineer’s Representative at least 14 days before the Tests on Completion are to be carried out.The Contractor shall be entirely responsible for the consequences of any delay by the Engineer’s Representative in agreeing to commission the Plant and equipment where such delay is due to errors, omissions or defects in the documents submitted by the Contractor. The Contractor shall make any further revision of the manuals required or agreed by the Engineer’s Representative and shall provide one original hard copy and five hard copies of each manual in addition to soft copy on CD within a period of 28 days after the Tests on Completion have been completed. The manuals shall clearly describe with step-by-step procedures and diagrams the starting up, running and shutting down of each item of Plant or system.




They shall contain sufficient information to permit the Employer to take over, operate and maintain the Plant or system efficiently and effectively. Full spare parts lists shall be included together with ordering procedures. The manuals shall be of high quality in both presentation and technical content presentation and technical content. Manual not meeting this standard will be rejected.


3. EXCAVATION, TRENCHING AND BACKFILLING

3.1Site InvestigationThe Contractor shall be deemed to have visited the site of Works and satisfied himself as to the nature of the ground and made himself conversant with the local conditions to be encountered during the execution of the Contract.

3.2 MaterialsConstruction materials supplied by the Contractor shall include but not be limited to the following:

Backfill: Backfill and fill shall be structurally sound material such as sand or native soil free of rocks, lumps, vegetable and other organic materials, obtained from suitable excavated material and/or from approved borrow pits. The backfill shall be appropriate for the existing road or paving construction to be reinstated as required.

Water shall be clean potable water free from injurious amounts of oil, acid or any other deleterious mineral and/or organic matter.

Concrete for thrust blocks, chambers, cover slabs or used as fill for making up to correct level and areas of over-excavation, shall have a characteristic strength of 25 N/mm2.

Pipe bedding and surrounds shall be sand.

The sand shall be clean coarse sand free from dirt or organic materials.

3.3 Site PreparationPrior to commencing any excavation work, the Contractor shall establish a horizontal and vertical survey network, record existing ground elevations and stake the location of trenches to be excavated.

The Contractor shall prepare the site for construction by clearing, removing and disposing of all items not indicated on the Drawings to remain or so defined by the Engineer or his representative.

3.3.1 Existing UtilitiesThe Contractor shall ascertain the whereabouts of all existing utilities on the site both, above and below ground.

The Contractor shall be held responsible for all damages entailed on any of the utilities adjacent to the site resulting from the Works.

All proposed or existing utilities, including buried pipes, sewers, ducts, culverts, cesspits, chambers and the like, in the vicinity of the work site, are to be determined by the Contractor and the location of them is to be shown on the as-built drawings.

Prior to commencement of excavation, the Contractor shall establish the number and location of underground utilities and chambers in the immediate proximity of the work.

Where necessary, the Contractor shall use hand tools to excavate test pits prior to excavation to determine the exact locations of existing utilities. It shall be the responsibility of the Contractor to make such explorations sufficiently in advance of construction to enable the Engineer or his representative to approve modifications, if any, to be made to the pipeline, structure or conflicting utility. The Contractor shall obtain the permission of the Engineer or his representative before commencing any test pits and shall fence, mark and protect them, as required by the Engineer or his representative. Test pits shall be refilled by hand as soon as practicable after the necessary information has been obtained.

As the excavation approaches sewers conduits, cables or other underground facilities, the excavation shall be continued with care by means of hand tools. Where necessary, the Contractor shall provide


temporary support for the existing utilities to prevent damage during his operations. Notwithstanding these provisions, if damage to existing utilities results from the Contractor's operations, such damage shall be repaired without delay by the Contractor to the Utility Engineer or his representative’s satisfaction.

If damage to existing utilities causes disruption to Contractor's schedule of work by delaying work in the area of such damage, the Contractor shall re-adjust his program, methods of working and resources so that critical dates in the schedule for the completion of the Contract are not affected. This shall not be deemed to be an instructed acceleration.

3.3.2 Cleaning And GrubbingThe Contractor shall perform the clearing and grubbing (if any), of top soil consisting mainly of loose soil, vegetable and organic matters, drift sand, unsuitable soil and rubbish by scarifying the areas to be excavated and sidewalks to a minimum depth of 300mm from the natural ground level. All materials resulting from the above operations shall be removed from the site, loaded and transported and off loaded, spread and leveled to approved municipal dumps.

3.4 ExcavationThe Contractor shall perform all excavation true to line, width and depths shown on the Drawings or to such further lines, depths or dimensions or to reach suitable bearing strata as may be directed by the Engineer or his representative.

Excavation for structures includes reduction of levels where indicated, excavation for manholes, foundations, supports, and other structures, in accordance with the specific set of Drawings. All such excavations shall be carried out to the dimensions, lines and grades as shown on the Drawings, or directed by the Engineer or his representative. Where necessary because of the depth of the excavations or the nature of the soil, the Contractor shall prevent caving in or slides by either excavating to slopes or installing sufficient shoring braces or supports. Excavations on or against which concrete or compacted fill is to be placed, shall be clean and free from stones, clods, debris and other loose material.

Where the bottom of an excavation does not provide a solid basis for casting concrete, it shall be consolidated by tamping and/or watering as necessary until the required base density is obtained. Any over-excavation in the bottom of the structure shall be cleaned and backfilled with concrete or selected backfill compacted to the density of the adjacent natural soil or 95% relative density using modified Proctor test, whichever is greater. Over-excavation in rock shall be backfilled with the concrete of the structure or with dry stone pack, as directed by the Engineer or his representative.

3.4.1 Keeping Excavations Free From WaterAll excavations shall be kept clear of water by pumping or bailing or by well-point de-watering, but the latter system shall not be employed if any danger exists withdrawing water from the foundations of the adjoining buildings and such water shall be discharged clear of the Works and the method adopted shall in no way contravene with regulations of the Municipalities.

The system or systems to be employed shall be approved by the Engineer or his representative. Such approval if given, shall not waive the Contractor's responsibilities and liabilities under the Contract.

Particular attention shall be paid to the installation of sheeting and shoring as may be necessary for the protection of the work and for the safety of personnel and public.

3.4.2 Storing Of Suitable Excavated MaterialDuring excavation, materials suitable for backfill shall be stockpiled on the site at adequate distance from the sides of the excavation to avoid over-loading and prevent collapse of the trench walls.

3.4.3 Disposal Of Unsuitable And Surplus Excavated MaterialUpon the order of the Engineer or his representative, all unsuitable and surplus materials shall be immediately removed, loaded and transported off the site area by the Contractor to approved dumps and he shall abide by the relevant local regulations.


3.5 Sheeting, Shoring And BracingExcept where banks are cut back on a stable slope, excavation shall be sheeted, braced and shored as necessary to prevent collapse of the excavations. The Contractor shall furnish, put in place, and maintain such sheeting, bracing, etc..., as may be necessary to support the sides of the excavation and to prevent any movement of earth which could in any way diminish the width of the excavation to less than that necessary for proper construction, or could otherwise injure or delay the work, or endanger adjacent structures. If the Engineer or his representative is of the opinion that at any point sufficient proper supports have not been provided, he may order additional supports.

The Engineer or his representative may direct that sheeting and bracing be cut off at any specified elevation.

All sheeting and bracing not to be left in place shall be carefully removed in such manner as not to endanger the construction or other structures. All voids left or caused by the withdrawal of sheeting shall be backfilled immediately with approved material and compacted by ramming with tools especially adapted to that purpose, by watering or by other means as may be directed.

3.6 Trench Excavation

3.6.1 General RequirementsTrench excavation work shall be performed in a safe and proper manner with appropriate precautions being taken to safeguard workmen and existing structures and utilities against all hazards.

All trench excavation shall be open cut from the surface unless authorized by the Engineer or his representative and shall be excavated so that pipes can be laid straight at uniform grade without dips or humps between terminal elevations indicated on the Drawings.

No more trench shall be opened in advance of pipe laying than is necessary to expedite the work. The maximum length of open trench on any line under construction shall be 50m.

The pipe is to be laid in sand bedding, as indicated on the Drawings or directed by the Engineer or his representative. The trench is to be excavated by labour to, or to just below, the designated sub-grade, provided that the material remaining at the bottom of the trench is not disturbed. The pipe is not to be laid directly on the trench bottom.

Whenever unstable soil which in the opinion of the Engineer or his representative is incapable of properly supporting the pipe is encountered in the bottom of the trench, such soil shall be removed to the depth instructed and the trench backfilled to the proper grade with sand approved by the Engineer or his representative.

3.6.2Mechanical ExcavationThe use of mechanical equipment will not be permitted in locations where its operation would cause damage to trees, tree roots, buildings, culverts or other existing property, utilities or structures above or below ground. In all such locations hand excavation shall be used.

Mechanical equipment if used for trench excavation shall be of type approved by the Engineer or his representative. Equipment shall be so operated that the rough trench excavation bottom can be controlled, that uniform trench widths and vertical sidewalks are obtained at least from an elevation 20cm above the top of the installed pipe when accurately laid to specified alignment will be centered in the trench with adequate clearance between the pipe and sidewalks of the trench.

3.6.3Alignment And Minimum CoverThe alignment of each pipeline shall be fixed and determined from offset stakes. Horizontal alignment of pipes and the maximum joint deflection used in connection therewith, shall be in conformity with requirements of the section covering installation of pipe.


Pipe grades or elevations are not definitely fixed by the Drawings, trenches shall be excavated to a depth sufficient to provide a minimum depth of backfill cover over the top of the pipe of 100cm for main lines with surface traffic, 80cm for main lines with no traffic including pavements and 60cm for house connections. Greater pipe cover depths may be necessary at certain locations, the locations and depths will be determined by the Engineer or his representative. Measurement of pipe cover depth shall be made vertically from the outside top of pipe to finish ground or pavement surface elevation except where future surface elevations are indicated on the Drawings. Where there is no adequate minimum cover, concrete encasement shall be used as detailed on the Drawings or as directed by the Engineer or his representative.

3.7Depth Of TrenchThe depth of trench shall be the sum of the specified cover to pipe plus pipe O.D plus 15cm minimum. The trench bottom shall be straight and even so as to provide a good support for the pipe along its entire length and shall be free of roots, stones, lumps and other hard objects that may injure the pipe or its protective coating as applicable. The sand bedding under the pipe shall be not less than 15cm.

3.8 Width Of TrenchNo wide unsupported trenches shall be permitted, in general, within the area of the works and therefore all trenches should conform to the minimum trench widths stated and shall be supported with the use of approved trench sheeting or sheet piles.

Pipe trenches shall be made as narrow as practicable and shall not be widened by scraping or loosening materials from the sides. Every effort shall be made to keep the sides of the trenches firm and undisturbed until backfilling has been completed and consolidated.

To allow sufficient working room plus trench wall supports, the minimum excavated trench width to the outside of the sheeting or shield box shall be as shown in the following values:

Nominal Pipe Size Diameter, (mm)

Trench Width, Minimum ( m )

Trench Width, Maximum (m)

200 0.90 2.50315 1.00 2.50450 1.20 2.65500 1.30 2.65630 1.40 2.65710 1.50 2.95750 1.55 2.95800 1.60 3.35900 1.70 3.351000 1.80 3.35

Widths are based upon 200 to 400mm clearance on each side of the pipe to the inner face of trench supports. The trench supports are assumed to be 150mm thick trench box or shield walls or 100 mm walls inside of 50mm sheeting. Exceptionally deep trenches with thicker sheeting and bracing or other systems of trench support may require the Engineer or his representative to vary these trench widths. Timber sheeting, where used below the top of the pipe, shall be driven approximately 60cm below the bottom of the pipe and be left in place approximately 45 cm above the top of pipe. In supported trenches compaction of foundation and embedment materials should extend to the trench wall or sheeting left in place.

In confined areas, where the passage of excavating equipment is impossible, or where the Engineer or his representative deems the use of such equipment impracticable or undesirable for any reason


whatsoever, trench excavation shall be done by hand. All requirements specified above for common excavation shall apply to trench excavation.

3.9 Unauthorized ExcavationExcept where specifically stated otherwise all the provisions of this section shall equally apply to both common and rock excavation. All excavation shall be done to the lines, grades and dimensions shown on the Drawings and within the tolerances given by the Engineer or his representative.

If the bottom of any excavation is taken out beyond the limits indicated or prescribed, the resulting void shall be backfilled at the Contractor's expense with thoroughly compacted, selected screened gravel or sand fill as directed by the Engineer or his representative if the excavation was for a pipeline, or with concrete if the excavation was for a structure or a manhole.

3.10 Elimination Of Unsuitable MaterialSuitable material shall comprise all material that is acceptable in accordance with the Contract for use in the Works. Suitable material for earthworks shall be approved soil with a plasticity index not exceeding 6% obtained from excavations within the Works or from borrow pits approved by the Engineer or his representative. It shall not contain an excess of fines.

Unsuitable material shall be deemed to be: - Rock particles exceeding 75mm in size. - Organic material, stumps and other perishable material. - Material susceptible to spontaneous combustion. - Soils of liquid limit exceeding 40% and/or plasticity index exceeding 6%. - Any other material which the Engineer or his representative may deem to be unsuitable for earthwork.

If material unsuitable for foundation (in the opinion of the Engineer or his representative) is found at or below the grade to which excavation would normally be carried in accordance with the Drawings and/or structure, the Contractor shall remove such material to the required width and depth and replace it with compacted, selected screened gravel, sand fill or concrete as directed by the Engineer or his representative.

3.11 Disposal Of Surplus Excavation MaterialsAll surplus excavated materials shall be disposed of by the Contractor, except as otherwise directed or approved by the Engineer or his representative.

3.12 BackfillingIn general, and unless other material is indicated on the Drawings or specified, material used for backfilling trenches and excavations around structures shall be suitable material.

Backfilling of pipe trenches, (except at joints) shall be done as practicable after the pipes have been satisfactorily laid in position and jointed and in no case shall more than five pipe lengths be left uncovered after laying. The first stage of the backfill, from the bedding surface and up to 30 cm above the top of the pipe, shall consist of granular material as specified in section 1.15 obtained from trench excavation or from borrow areas, free from stones, clods, and organic matter. This backfill shall be hand-tamped under and around the pipe in layers not exceeding 15 cm in thickness after compaction, to a density not less than that required for the subsequent backfill. (at least 95% of modified Proctor).

The remainder of the pipe trench (second stage backfill from 30 cm above the pipe to the top of the trench) shall be backfilled by one of the following methods:

a) Where the pipeline runs transversely underneath asphalt paved roads highways, the second stage backfill shall be done with selected excavated material or imported material as specified in section 1.20, and shall be placed in layers not exceeding 15 cm thickness after compaction, wetted as necessary and compacted to a density not less than that of the adjacent material or compacted soil. (at least 95% of modified Proctor). As shown on


the Drawings or directed by the Engineer or his representative, the top of the trench backfill shall consist of four layers with total thickness of 38 cm, the first layer is of crushed aggregate base course layer 15 cm thick and the second layer of 15 cm thickness of crushed aggregate base course layer mixed with cement in the proportions of 7:1, with each layer wetted as necessary and compacted to a density at least 98% of modified Proctor. The third layer shall be asphalt base course layer of 40 mm thick of (3/4") aggregate size and the fourth layer shall be asphalt wearing layer of 40 mm thick of (1/2") aggregate size. MC70 and RC70 are used for priming the base course and between the two asphalt layers at a rate of 1.00 kg per m2

and 0.50 kg per m2, respectively. Edges of asphalt shall be sawed into straight lines with no curves or abrupt edges; with berm width of 15cm on either side of the trench and to a depth of 8cm. All crossing shall be of one straight segments. The Contractor is responsible for cutting, removing and reinstating all pavements cracked or destroyed as a result of his Work.

b) Where the pipeline runs longitudinally underneath asphalt paved roads highways, the second stage backfill shall be done with selected excavated material or imported material as specified in section 1.20, and shall be placed in layers not exceeding 15 cm thickness after compaction, wetted as necessary and compacted to a density not less than that of the adjacent material or compacted soil. (at least 95% of modified Proctor). As shown on the Drawings or directed by the Engineer or his representative, the top of the trench backfill shall consist of four layers with total thickness of 38 cm, the first two layers shall be of crushed aggregate base course layers 15 cm thick, each wetted as necessary and compacted to a density at least 98% of modified Proctor. The third layer shall be asphalt base course layer of 40 mm thick of (3/4") aggregate size and the fourth layer shall be asphalt wearing layer of 40 mm thick of (1/2") aggregate size. MC70 and RC70 are used for priming the base course and between the two asphalt layers at a rate of 1.00 kg per m2 and 0.50 kg per m2, respectively. Edges of asphalt shall be sawed into straight lines with no curves or abrupt edges; with berm width of 15cm on either side of the trench and to a depth of 8cm. Each straight segments shall not be less than 50m. The Contractor is responsible of cutting, removing and reinstating all pavement cracked or destroyed as a result of his Work.

c) Where the pipeline runs longitudinally underneath concrete pavement, the second stage backfill shall be done with selected excavated material or imported material as specified in section 1.20, and shall be placed in layers not exceeding 15 cm thickness after compaction, wetted as necessary and compacted to a density not less than that of the adjacent material or compacted soil at least 95% of modified Proctor. As shown on the Drawings or directed by the Engineer or his representative, the top of the trench backfill shall consist of two layers the first top layer shall be crushed aggregate base course 15 cm thick wetted as necessary and compacted to a density at least 98% of modified Proctor and the second layer of 10 cm thickness of plain concrete B200

d) Where the pipeline runs underneath tile paved roads, the second stage backfill shall be done with selected excavated material or imported material as specified in section 1.20, and shall be placed in layers not exceeding 15 cm thickness after compaction, wetted as necessary and compacted to a density not less than that of the adjacent material or compacted soil at least 95% of modified Proctor. As shown on the Drawings or directed by the Engineer or his representative, the top of the trench backfill shall consist of three layers the first top layer shall be crushed aggregate base course 20 cm thick wetted as necessary and compacted to a density at least 98% of modified Proctor and the second layer of 5cm thickness of fine granular material and the third layer of 8cm thickness of concrete tiles.

e) Where the pipeline crosses tile-paved sidewalk or island, the second stage backfill shall be done with selected excavated material or imported material as specified in section 1.20, and shall be placed in layers not exceeding 15 cm thickness after compaction, wetted as necessary and compacted to a density at least 95% of modified Proctor. As shown on the Drawings or directed by the Engineer or his representative, the top of the trench backfill


shall consist of three layers with total thickness of 21 cm, the first layer shall be crushed aggregate base course 10 cm thick wetted as necessary and compacted to a density at least 98% of modified Proctor and the second layer shall be 5 cm thick of fine granular material. The third layer shall be concrete tiles 6 cm thick or similar to existing tiles with 2cm mortar, if any.

f) Where the pipeline crosses an asphalt paved sidewalk or island the second stage backfill shall be done with selected excavated material or imported material as specified in section 1.20, and shall be placed in layers not exceeding 15 cm thickness after compaction, wetted as necessary and compacted to a density at least 95% of modified Proctor . As shown on the Drawings or directed by the Engineer or his representative, the top of the trench backfill shall consist of two layers with total thickness of 15 cm, the first is of crushed aggregate base course layer 10 cm thick wetted as necessary and compacted to a density at least 98% of modified Proctor and the second layer shall be asphalt wearing layer of 5 cm thickness of (3/8") aggregate size. MC70 is used for priming the base course at rate of 1 kg/m2. Edges of asphalt shall be sawed into straight lines with no curves or abrupt edges;

g) Where the pipeline runs longitudinally underneath a road’s unpaved shoulder, the second stage backfill shall be done with selected excavated material or imported material as specified in section 1.20, and shall be placed in layers not exceeding 15 cm thickness after compaction, wetted as necessary and compacted to a density not less than that of the adjacent material or compacted soil at least 95% of modified Proctor. As shown on the Drawings or directed by the Engineer or his representative, the top of the trench backfill shall consist of crushed aggregate base course layer 15 cm thick, wetted as necessary and compacted to a density at least 98% of modified Proctor.

h) Where the pipeline runs longitudinally underneath a road’s paved shoulder, the second stage backfill shall be done with selected excavated material or imported material as specified in section 1.20, and shall be placed in layers not exceeding 15 cm thickness after compaction, wetted as necessary and compacted to a density not less than that of the adjacent material or compacted soil at least 95% of modified Proctor. As shown on the Drawings or directed by the Engineer or his representative, the top of the trench backfill shall consist of two layers with total thickness of 20 cm, the first is of crushed aggregate base course layer 15 cm thick, wetted as necessary and compacted to a density at least 98% of modified Proctor and the second layer of 5cm thick of asphalt wearing (1/2") aggregate size. MC70 is used for priming the base course at rate of 1 kg/m2. Edges of asphalt shall be sawed into straight segments with no curves or abrupt edges. Each straight segment shall not be less than 50m with width of 15cm on either side of the trench and to a depth of 5cm

i) In agricultural land or in natural ground roads of width less than 2.5m , where the requirements of para (a),(b),(c),(d),(e), (f), (g) and (h) do not apply, the second stage backfill may be done with selected excavated material, and shall be placed in layers not exceeding 30 cm after compaction, wetted as necessary and compacted to a density. (at least 90% of modified proctor). provided that the fill material does not contain any large stones.

j) In natural ground roads of width equal or more than 2.5m, where the above requirements do not apply, the second stage backfill may be done with selected excavated material as specified in section 1.20, and shall be placed in layers not exceeding 30 cm after compaction, wetted as necessary and compacted to a density. (at least 90% of modified proctor). provided that the fill material does not contain any large stones. The top of the trench backfill shall consists of one layer of 15cm thickness of natural material in accordance with the grading requirements in the Specifications, and shall be wetted as necessary and compacted to a density at least 95 % of modified proctor.

All joints, and other accessories shall be left uncovered until and after the pipeline shall have passed any leakage tests that may be prescribed by the Specifications

Where the backfill cover over the pipe is less than 100 cm, the travel of the trucks or heavy equipment thereon, will be strictly prohibited, and the Contractor shall be responsible for any damage caused to the pipe by non-compliance with this requirement.


3.13 Fill And Backfill Under StructuresUnless otherwise indicated or specified, all fill and backfill under structures shall be compacted. The percentage of compacting for backfill shall be 95% maximum density at optimum moisture content.

3.14 Backfilling Around StructuresThe Contractor shall not place backfill against or on structures until they have attained sufficient strength to support the loads (including construction loads) to which they will be subjected, without distortion, cracking or other damage as practicable after the structures are structurally adequate and other necessary work has been done, special leakage tests, if required, shall be made. Promptly after the completion of such tests, the backfilling shall be started and then shall proceed until its completion. Suitable material shall be used in backfilling. Unequal soil pressure shall be avoided by depositing the material evenly around the structure.

The material shall be placed and compacted as specified below, insofar as applicable. Compacting shall be accomplished by water-jetting or pudding, if the nature of the material permits, otherwise by tamping.

Walls with fill on both sides shall have the fill constructed such that the difference in the top elevation of the fill on the two sides does not exceed 60cm at any time.

3.15 Backfilling Material

3.15.1Granular BackfillThe material shall consist of natural silica sand subject to approval of the Engineer or his representative, other inert materials with similar characteristics having durable particles.

Materials from different sources of supply shall not be mixed or stored in the same pile nor used alternately in the same class of construction without permission from the Engineer or his representative.

The granular material shall be uniformly graded and shall meet the following gradation requirements.

Sieve designation Passing Square-Mesh Sieves Percentages by Weight (AASHTO T 27)

3/8" 100No. 4 95 – 100No. 16 45 - 80No. 50 10 – 30No. 100 2 – 10

The material shall not contain deleterious substances in excess of the following percentages:AASHTO

Test MethodPercentage by Weight

Clay lumps T 112 1Coal and Lignite T 113 1Material passing sieve No. 200 T 11 3

Total deleterious substances including the above and shale, alkali, mica, coated grains, and soft and flaky particles shall not exceed 5 percent by weight.

The placing, compacting and testing of granular backfill shall conform to applicable requirements for select backfill as specified herein except as noted above.

The Contractor shall submit to the Engineer or his representative samples of proposed Granular Backfill. The proposed material must receive the approval of the Engineer or his representative prior to using of it on the project. The Contractor will be permitted to use excess materials from the trench provided that they conform to the above requirements.


3.15.2Select BackfillSelect backfill shall be placed as shown and specified or where directed by the Engineer or his representative. All materials used as select backfill shall consist of well-graded clean sand or sand and gravel meeting the following gradation requirements:

Sieve Size Percent Passing by Weight 1" 100No. 4 30 – 100No. 40 0 – 40No. 200 0 – 10

No material containing pieces of wood or other organic matters or having lumps, pockets or concentrations of silt or clay will be accepted. Samples of proposed backfill material should be submitted to the Engineer or his representative for testing and approval prior to using of the backfill. The Contractor shall certify that for samples submitted, sufficient similar material is available to complete the Work. No backfill shall be placed at the Site without approval by the Engineer or his representative. The Engineer or his representative shall be permitted access to borrow pits at all times for purposes of inspection.

Prior to placement of select backfill, the surface of the subgrade shall be levelled and shall be compacted with two complete coverage using equipment approved for backfill placement. Engineer or his representative shall approve the subgrade prior to backfill placement. All backfill shall be placed in horizontal loose lifts not exceeding the thickness specified in section 1.17 para (a), (b), (c), (d), (e) and (f), and shall be mixed and spread in a manner assuring uniform lift thickness after placing. Each layer of backfill shall be properly compacted as specified herein before placement of the following lift. Backfill against foundation walls shall not be placed until obtaining the approval of the Engineer or his representative. The backfill shall be performed in a manner that will not create unbalanced pressure that could damage completed Work.

Backfill material may be placed in either a dry or a wet condition. Any material which is in the “bulking” range of the moisture content of the material shall be saturated before compaction. No backfill material shall be placed when free water is standing on the surface of the area where the backfill is to be placed. No compaction of backfill will be permitted with free water on any portion of the backfill to be compacted. Any backfill containing organic materials or other unacceptable material previously described shall be removed and replaced with approved backfill material prior to compaction.

Compaction of backfill shall be performed as specified, with equipment suitable for the type of backfill material being placed. The Contractor shall select equipment capable of providing the minimum density required by these Specifications or in cases where the compaction equipment is specified, this specified equipment shall be used, and shall submit information pertaining to the equipment to the Engineer or his representative for approval. Equipment shall be capable of compacting in restricted areas next to structures and around piping without damaging same.

Each lift of backfill material shall be compacted by at least two coverages of all portions of the surface of each lift by approved compaction equipment. One coverage is defined as the condition obtained when all portions of the surface of the backfill material have been subjected to the direct contact of the compacting surface of the compactor. The minimum density to be obtained in compacting select backfill shall be 95 percent of maximum density obtained in the laboratory in accordance with Palestinian Standard. This percentage is of standard Proctor density. Compaction tests, soil analyses and any other laboratory tests necessary in the opinion of the Engineer or his representative for proper completion of the work shall be performed by the Contractor.

The water content of the fill shall be controlled during placement within the range necessary to obtain the compaction specified. In general, the moisture content of backfill soils shall be within 3 percent of the optimum moisture content for compaction as determined by laboratory tests. All laboratory tests necessary to establish that the water content of the backfill is suitable for placement shall be performed by the Engineer or his representative. The Contractor shall perform all necessary work to adjust the


water content of the backfill material to be within the range necessary to permit the compaction specified. This shall include, but not be limited to, spreading, scarifying and mixing to permit drying to reduce natural water contents to an acceptable range or adding water to increase the water content to an acceptable level.

The Contractor shall perform whatever tests he deems necessary to provide data for his selection of backfill material and control of water content. Copies of a test results shall be furnished to the Engineer or his representative for his review.

If the field and laboratory tests indicate unsatisfactory compaction, the Contractor shall provide the additional compaction necessary to obtain the specified degree of compaction. All additional compaction work shall be performed and paid for by the Contractor until the specified compactions is obtained.

If the specified densities are not being obtained because of the Contractor’s improper control of placement or compaction procedures or because of improperly functioning compaction equipment, the Contractor shall perform whatever work is required to provide the specified densities. This work shall include complete removal of unacceptable backfill areas and replacement and re-compaction until acceptable backfill is provided. All additional work to provide acceptable backfill shall be performed and paid for by the Contractor. In-place density determinations shall be made by an approved laboratory using a sand density cone or equivalent method as specified by Palestinian Standard.

The Contractor shall submit to the Engineer or his representative samples of proposed select backfill. The proposed material must receive the approval of the Engineer or his representative prior to using of it on the project. The Contractor will be permitted to use excess materials from the trench provided they conform to the above requirements.

3.15.3Gravel Or Crushed Stone BackfillGravel or crushed stone backfill shall consist of gravel, crushed stone, crushed rock, material sands, manufactured sands or combination thereof, and shall conform to the following gradation requirements:

Screening size Percentage passing by Weight2" 100

No. 4 30 – 100No. 40 0 – 30No. 200 0 - 5

The portion of the backfill passing the No. 4 screen shall have a sand equivalent of not less than 60 percent.

Gravel or crushed stone backfill shall be placed as shown and specified or where directed by the Director or Works or his representative.

Gravel or crushed stone shall be spread in layers of uniform thickness not exceeding 20 cm and shall be thoroughly compacted with suitable power driven tampers or other power driven equipment. The placing, compacting and testing of gravel or crushed stone shall conform to applicable requirements for select backfill as specified herein except as noted above.

The Contractor shall submit to the Engineer or his representative samples of proposed gravel or crushed stone backfill. The proposed material must receive the approval of the Engineer or his representative prior to using of it on the project. The Contractor will be permitted to use excess materials from the trench provided that they conform to the above requirements.

3.16 Preparation Of Sub-gradeThe Contractor shall remove loam topsoil, loose vegetable, matter, stumps, large roots, etc..., from areas upon which material will be placed for grading. The sub-grade shall be shaped as directed by the Engineer or his representative and shall be so prepared for forking, furrowing or plowing that the first layer of the new material placed therein will be well bonded to it.


4. MANHOLES AND CHAMBERS

4.1GeneralAll chambers and manholes to be supplied by the Contractor. The work covered by this section of the specification shall consist of furnishing all plant, labor, equipment, appliances and materials, and performing all operations necessary in the construction of manholes in accordance with the specifications and the drawings and subject the terms of the conditions of contract

Concrete, reinforced concrete, concrete blocks and reinforcement bars shall be as specified under concrete. All pipes shall be as specified under pipe and pipe laying. Materials and allowable loads in cast iron frames and covers shall comply with British standard 497, and as specified hereinafter.

4.2 CleaningAll manholes and valve chambers specified under this section shall be cleaned of any accumulation of silt, mortar, debris or any other foreign matter of any kind and shall be free of any such accumulations at the time of final inspection.

4.3 Construction Of Manholes And Valve ChambersAll manholes and chambers shall have concrete bases. The Contractor shall construct all manholes, chambers, and special structures including transition chambers and outfall structures as indicated on the Drawings and herein specified.

Manholes, chambers, and special structures shall conform in shape, size, dimensions, materials, and other respects to the details indicated on the Drawings or as ordered by the Engineer or his representative.

Manhole and chamber cover slabs shall be either pre-cast or cast in place reinforced-concrete as marked on the Drawings. The cast iron frames and covers for manholes and chambers shall be brought to grade by the number of courses of concrete blocks shown on the Drawings and a reinforced concrete frame into which the cast iron frame is embedded. Class B concrete shall be cast to a minimum thickness of 150mm around the concrete blocks for rigidity.

Manhole walls (rings) and cover slabs shall be either pre-cast or cast in place reinforced-concrete. In pre-cast construction rubber rings are to be placed in all joints except for the joint between the cast in place roof slab and the top wall ring. In below the manhole cover slab shall have removable plus or minus 30cm high concrete ring.

The cast iron frames and covers for manholes shall be brought to grade by a maximum of three courses of concrete blocks and a reinforced concrete frame into which the cast iron frame is embedded. Manhole frames shall be set with the tops conforming accurately the grade of the pavement or finished ground surface or as indicated on the drawings directed. The cast iron manhole frames and covers shall be as indicated on the drawings and hereinafter specified .The inverts shall conform accurately to the size of the adjoining pipe Side inverts shall be curved and main inverts (where direction changes) shall be laid out in smooth curves of the longest possible which is tangent, within the manhole the centerlines of adjoining pipelines all as indicated on the drawings and approved by the Engineer or his representative. All benching indicated shall be class B300 Concrete. Class B200 should be used for plain concrete.

External and internal form work for all manholes shall be in accordance with the requirements of the specifications. The use of the sides of the excavations instead of external form works is not allowed. Internal surfaces of all manholes shall be smooth finished by the used of steel forms, plywood or timber with one face treated to a smooth surface, indicated with two coats of coal tar epoxy compound. The internal surfaces of the manholes will be plastered with cement mortar using 1: 5 mix and 1.0cm thickness.

Manholes shall be completely constructed as the works progress and as each one is reached by the pipe work.


Manhole frames and covers shall be placed immediately after the completion of the manhole. If not defined elsewhere, the depth shall be taken as the difference between the top of the manhole and the base of the manhole.

The contractor shall furnish all cast-iron frames and covers conforming to the details shown on the drawings, or as herein before specified. As described in the general specifications, the contractor shall submit for approval detailed shop and working drawings of all casting before fabrication.

The castings shall be of good quality, strong, tough, even grained cast iron, smooth, free from scale, lumps, blisters, sand holes, and defects of every nature which would render them unfit for service for which they are intended.

For mainlines cast iron heavy duty covers of 120kg weight and 25 tons bearing capacity will be used, for laterals and sub-laterals cast iron medium duty covers of 50kg weight and 8 tons bearing capacity will be used. They shall have a rubber ring installed at the inner surface of the cover and frame seating to ensure non-rocking under traffic.

Before being shipped from the foundry, castings shall be given one coat of coal-tar pitch in a satisfactory manner so as to make a smooth coating, tenacious, and not brittle or with any tendency to scale off.

4.4 Formwork Of Valve ChambersThe Contractor shall be responsible for the design and stability of the formwork. The Contractor shall submit a full program of work indicating the various phases for the erection and removal of forms and the manner in which he intends to execute.

4.5Pre-Cast ElementsPre-cast elements shall be either of concrete or mortar as shown on the Drawings and as specified hereinafter.

4.5.1 Pre-Cast Concrete ElementsPre-cast concrete elements shall be of plain or reinforced concrete dimensions, thickness and reinforcement rods and bars shown on the Drawings and stated in the Bill of Quantities.

4.5.2 Pre-Cast Mortar ElementsMoist tamped mortar pre-cast elements shall be of a mixture of ordinary or tinted cement and sand (fine aggregate) approximately in the proportions of one part cement to two and one-half parts of sand. The sand shall be specially selected for color and grading. The sand shall be screened through 1/8" inch square meshes and all oversize particles shall be discarded. Only sufficient water shall be used in mixing to permit the immediate removal of the member from the mould. The pattern, dimensions and thickness shall be as shown on the Drawings and/or as directed in writing by the Engineer or his representative.

4.5.3 MortarMortar for joining the pre-cast elements shall be composed of one part of Portland cement and three parts of clean sand unless otherwise specified. The cement and sand shall conform to the requirements of ordinary Portland cement and aggregate for mortar specified heretofore.

4.5.4 FabricationPre-cast concrete or mortar elements shall be cast in mortar-tight metal lined timber moulds and shall be mechanically vibrated when cast. The Pre-cast elements shall be removed from the moulds as soon as practicable and shall be kept. damp for a period of at least 10 days. Any elements that shows checking or soft corners or surfaces shall be rejected. The method of storage and handling shall be such as to preserve true and even edges and corners, any pre-cast element which becomes chipped, marred or cracked before or during the process of placing shall be rejected, sampling of pre-cast elements shall be submitted to the Engineer or his representative for approval, prior to fabrication, at the Contractor's own expense.


4.5.5 WorkmanshipAll pre-cast concrete or mortar elements shall be well cleaned and thoroughly wetted with clean water before placing in their positions shown on the Drawings. The pre-cast elements shall be bedded and jointed in cement and sand mortar (1:3) mix and the joints raked out on both faces to receive plaster or pointing as indicated on the Drawings to the satisfaction of the Engineer or his representative.

4.6 Manholes Protective CoatingThe interior walls of the manholes in contact with waste water shall be painted with epoxy paint on concrete in two layers at least and until a uniform color is attained and as per the manufacturer’s recommendations.

4.7 Connection Of A Sewer To An Existing SystemThe following specifications include the requirements for executing the following works:

Concoction of a sewer to an existing manhole Construction of a manhole on an existing sewer.

4.7.1 Safety RegulationsWhenever any work or repair/or connection to existing sewers is about to be executed, the contractor shall inspect and test such sewers for the presence of dangerous gases by means of detection torches or similar devices and shall take all necessary precautions and protective measures, which shall include, but not limited to, the following:

Before entry into a manhole, the absence of noxious gases and availability of oxygen in it must be ascertained. Should any noxious gases or lack of oxygen in it be discovered, no entry shall be made until the manhole has been thoroughly ventilated with the aid of blowers. Only after all gases have been removed and sufficient oxygen has been introduced, will entry be permitted, but only to personnel wearing gas masks.

Manhole covers shall be opened to ventilate pipelines for 24 hours, at least, as follows: For work in an existing manhole: the cover of the manhole upstream and downstream of it. A

total of three covers. For connection to a sewer: the covers of the manholes upstream and downstream of the

connections. no entrance into a manhole shall be permitted unless at least one person stays outside the

manhole in readiness to render assistance if required. The person entering the manhole shall wear rubber gloves and rubber knee-boots with acid

resistant soles. He shall also wear a safety harness with lifting rope, the end of which will be held by the person outside the manhole.

persons entering the manholes deeper than 3.0m shall wear suitable gas masks. Mechanical ventilation by blower must be employed prior to entry and throughout the work in

manholes deeper than 5.0m. Personnel employed on work requiring entry into manholes, septic tanks, etc. shall be briefed

on the above noted safety measures and drilled in the use of harnesses, gas masks, etc. The provisions of this section shall in no way be construed as relieving the contractor from full

and complete responsibility for the safety of his workmen and any other person who may suffer accident or injury due to the works carried out by the contractor.

4.7.2 Permission To ProceedThe contractor must receive written permission from the Engineer or his representative before executing any of the previous described works. In all cases permission to proceed should be recorded in the works diary by the Engineer or his representative.


5. CONCRETE WORKS5.1GeneralConcrete work shall consist of furnishing all materials and constructing structures of the forms, shapes and dimensions shown on the Drawings or as directed, using Portland Cement Concrete, in accordance with the details shown on the Drawings and these Specifications.

5.2ClassificationThe concrete is classified on the basis of its characteristic strength in compressive at 28 days as shown in the following table

Concrete Class Comp. Strength @ 28 day for

Cylinder 15x15x15 cm cubeB 300 300kg/cm2 ( 4260 psi ) 345kg/cm2 ( 4900 psi )B 250 250kg/cm2 ( 3550 psi ) 287kg/cm2 ( 4075 psi )B 200 200kg/cm2 ( 2850 psi ) 230kg/cm2 ( 3270 psi )B 150 150kg/cm2 ( 2130 psi ) 180kg/cm2 ( 2555 psi )

Note : The concrete characteristic strength in compression (fcu) is the crushing strength at 28 days of cube 100x100x100mm cured in water for 7 days at 21 ± 2C° provided that the concrete characteristic strength of not more than 5% of the tested samples is allowed to be less than the specified strength in above table.

5.3AdmixturesAir entraining agents, plasticisers, water proofing agents, retarders, and other similar admixtures shall comply with Palestinian Standard Specifications and shall be used in accordance with the manufacturer’s recommendations and B.S. Samples of proposed admixtures shall, if required, be submitted to an approved testing authority by the Contractor in order to ascertain its suitability for use in the Works. Use of any admixtures must be approved before hand by the Engineer or his representative.

The cost of such admixtures shall be included in the cost of concrete and no extra payment shall be made if they are used. The proportions of cement, fine aggregate and water shall be determined by the Contractor before concreting commences and submitted together with such test results as may be required to the Engineer or his representative for approval and the Contractor shall not commence concreting before such approval is given nor shall he alter or vary in any way the proportion of mix unless he submits fresh test results and mix proportions to the Engineer or his representative for approval.

The approval by the Engineer or his representative of such mix designs does not in any way absolve the Contractor of any of the requirements of the Specifications.

5.4Mixing And Testing

5.4.1Samples Of AggregatesSamples of both fine and coarse aggregates are to be submitted to the Engineer or his representative for testing at least one week before commencing deliveries. No deliveries in bulk are to be commenced until such samples are approved by the Engineer or his representative as complying with this Specification.

5.4.2 Trial MixesFollowing the Engineer or his representative’s approval of the materials for each class of concrete, the Contractor shall prepare a trial mix of each grade of concrete in the presence of the Engineer or his representative. Each trial mix shall comprise not less than 1/3 of a cubic meter of concrete and shall be mixed in an approved type of concrete mixer similar to that which the Contractor propose to employ on the Works. The quantities of all ingredients of trial mix including water shall be carefully determined by weight according to the approved mix design. Each trial mix shall show no tendency to segregate when


handled and compacted by the methods by which the Contractor proposes to handle and compact the grade of concrete in the Works and it shall be capable of adequate compaction by such methods.

5.4.3 Water/Cement RatioThe quantity of water to be added to the cement and aggregates during mixing shall be just sufficient to produce a workable mix to enable it to be well compacted and worked into corners of formwork and around reinforcement. All mixes shall be designed in respect of the proportioning of water so that the Slump Test as carried out according to B.S. 1881 shall be in accordance with the slump specification. Measurement of water on the site shall take into account the moisture present in the aggregates , and Slump Tests shall be taken sufficiently frequently to ensure that variations in the moisture content of the aggregate are fully taken into account in determining the amount of water to be added.

5.4.4 Measurement Of IngredientsThe aggregates for the concrete shall be measured by weight but measurement by volume may be allowed in special circumstances with approval of the Engineer or his representative.

When the aggregates are to be measured by weight the weight batching machines shall be of a type approved by the Engineer or his representative. They shall be clean and in good condition and adjustment. At the Engineer or his representative may require, the Contractor shall check the accuracy of each weight-batching machine.

When the aggregates are to be measured by volume, the proportions of fine and coarse aggregates shall be measured in well constructed gauge boxes, of dimensions approved by the Engineer or his representative to guarantee that whole multiples of such gauge boxes wile-sure the use of one or more whole bags or containers of cement and the capacity of the concrete mixer shall be such as to ensure that no splitting of cement bags or containers is required. Gauge boxes shall be properly filled and struck off level, addition of fine aggregates to allow for bulking due to moisture content being made as required.

An efficient water measuring device shall be fitted to each concrete mixer. Any cement container shall be such as to contain an accurately weighed amount of cement.

5.4.5 Mixing Concrete The concrete shall be mixed in a power driven machine of the batch type, no hand mixing shall be permitted. Mixing shall continue until the mass of concrete batch is uniform in consistency and color. The method of discharge shall be such as to cause no segregation of the concrete materials.

Concrete which has commenced to set before placement shall not be re-mixed and shall be rejected and in no case used in the works.

5.4.6 Concrete Testing - Compressive Crushing StrengthA) GeneralThe methods used in sampling, making, curing and testing the concrete samples, either in the field or in the laboratory, will be in accordance with PS 55 Part 1 1997.Adequate facilities shall be provided for the Engineer or his representative to inspect ingredients and processes used in the manufacture and delivery of the concrete. The manufacturer and/or Contractor shall afford the Engineer or his representative, without charge, all facilities necessary to secure samples and conduct tests to determine whether the concrete is being furnished in accordance with the Specifications.

A part from the samples taken from the batching plant, to check the uniformity of production of the same, all samples taken in the field shall be taken at random from batches of concrete after leaving the mixer and under the Supervision of the Engineer or his representative. The quantity of samples and tests will be established by the Engineer or his representative, but each class of concrete shall be represented by at least one test (8) specimens, cubes 100x100x100mm) for each 75 cubic meter of concrete poured, but there shall be at least one test for each concrete poured for each day’s concreting regardless of the quantity.

The cubes shall be numbered consecutively and marked with the date, section of work form which they are taken and any other relevant information and tested at an approved laboratory. The first set of four cubes shall be tested after seven days.


B) 7 (Seven) day Tests and Acceptance of the Concrete WorksThe results of 7 day tests may be used as an indication of the compressive strengths which may considered to be 67% of strength at 28 days.

If the average strength of the four cubes tests after seven days is below 67 percent of the required strength after 28 days, the Contractor must immediately stop all concreting until checks are made on the material and equipment and immediately rectify any defect which has become apparent as the result of such checking. If the Contractor elects to remove and replace the defective concrete without waiting for the results of the twenty eight day test, concreting can then continue entirely at the responsibility of the Contractor otherwise, the second set of four cubes shall be tested, after 28 days.

C) 28 (Twenty eight) day Tests and Acceptance of the Concrete Works :The specified strength requirements shall be assumed satisfied if for any set of 4 consecutive test cubes none of the strengths is below the specified characteristic strength, or the average is not less than the specified characteristic strength and the difference between the greatest and least strength is not greater than 20%.

D) Concrete Testing - Workability Concrete shall be of a consistency and workability suitable for the conditions on the job. For most concrete a “plastic” mix is required, vibrated, without segregation.

The Contractor shall provide the equipment necessary to determine the slump of freshly-mixed concrete at each place where concrete is being placed and shall determine the slump of the concrete on each occasion that a set of test cubes is made and not less than once a day or as the Director or Works or his representative may direct.

Concrete delivered for placing, except as otherwise instructed by the Engineer or his representative, shall have a working slump limit ranging from 75 to 125 mm.

Whenever the working slump limit is out of the range mentioned above, the concrete shall be rejected and disposed at the Contractor’s expense.

The Engineer or his representative may choose to adopt lesser slumps whenever concrete of such lesser slump can be poured and consolidated readily in place by means of vibrators

E) Concrete Testing - Materials The Contractor shall also obtain and furnish the Engineer or his representative with current Material Test Certificates from the concrete supplier or otherwise for the following parameters;

Grading, fine and coarse aggregate Flakiness and Elongation Index Compacting Factor Test Co-efficient of expansion for the aggregates Absorption Index Mix Design

F) Requirements For The Concrete To Resist Chemical Attack. Sulphate-Resistance Portland Cement (SRPC) can be used for concrete to resist chemical attack as far as ultimate strength, durability, workability etc. are concerned. It is also essential to obtain a hardened concrete of low permeability. However, due to the very aggressive nature of acids, protective measures would have to be taken to prevent the acid coming in contact with concrete by using water proofing .

Full compaction of the concrete so as to reduce the permeability to a minimum is an essential factor in resisting sulphate attack even when SRPC is used. Workability and compaction can be improved by increasing the cement content of the mix to 330 kg/m3.


Waterproof coatings shall be applied to concrete structures in order to protect the concrete against the aggressive effects of saline ground water, generally, protective coatings will be applied to surface of structures which are close to or in contact with ground water.

Before applying any coating the surface of the concrete shall be cleaned of all dirt, dust and loose material and where necessary any surface shall be made good so that the surface is smooth and free from air or water holes. No coating shall be applied until the Engineer or his representative has approved the preparatory work. The coating shall be applied using approved bituminous coating with approved coatings.

5.5Transporting ConcreteConcrete shall be taken from the place of mixing to the place of deposition by methods which shall prevent the segregation or loss of the ingredients and which are sufficiently rapid to ensure that the concrete does not commence to set before it is compacted in position. The concrete shall be deposited as near as possible to its final position in the works and shall not be allowed to flow laterally into position. Deposition of the concrete through chutes shall not be permitted nor dropped freely from a height exceeding 1.50m.

5.6Placing Concrete - GeneralThe concrete shall be deposited generally in horizontal layers in such a manner as to maintain, until completion of the pour, a plastic surface approximately horizontal. The thickness of each layer shall range from 300 to 600mm as approved, and the placement shall be carried out at such a rate that no concrete surface can reach an initial set, before additional concrete is placed thereon and in any case not after 30 minutes (in the case that no retarding admixtures are used) or 2 hours (in the case that retarding admixtures are used).

The Engineer or his representative may authorize higher lifts or layers where concrete can be placed or consolidated in thick layers. Concrete shall be deposited, as nearly as practicable, directly in its final position, flowing of concrete with vibrators, or by other means will not be permitted. For locations where direct placement is not possible and in narrow forms, hoppers and trunks must be provided, of a size to allow proper placing.

Where steep slopes are required for placing concrete with chutes, the chutes shall be equipped with baffle boards or be in short lengths that reverse the direction of movement. Chutes and use of chutes must be approved by the Engineer or his representative.

All chutes, troughs and pipes shall be kept clean and free from coatings of hardened concrete by thoroughly flushing with water after each run. The water used for flushing shall be discharged clear of the concrete already in place.

Concrete shall not be dropped in the forms a distance of more than one and on half (1½) meters unless confined by approved closed chutes or pipes, and care shall be taken to fill each part of the form by depositing the concrete as near to the final position as possible. The coarse aggregate shall be worked back from the forms and worked around the reinforcement without displacing the bars. After initial set of the concrete, the forms shall not be jarred and no strain shall be placed on the ends of projecting reinforcement.

Any tendency to segregation shall be corrected by shoveling stone into mortar, rather than mortar into stones.

Concrete that is of excessive slump, segregated, partially hardened, or unworkable, shall not be placed in forms or if placed, shall be removed and wasted as directed by the Director or Works or his representative, at the Contractor’s expense.

Each layer of the concrete shall be worked with suitable types of equipment, until the concrete is consolidated to the maximum practicable density, is free of pockets of coarse aggregate, and fits tightly against all form surfaces and embedded materials.

Construction equipment used for spreading, vibrating or other operations must absolutely not spatter loose oil, fuel and grease on the concrete.


No concrete work shall be stopped or temporarily discontinued within forty five (45) centimeters of the top of any finished surface, unless such work is finished with a coping having a thickness less than forty five (45) centimeters, in which case the joint shall be made at the under edge of the coping.

5.7Concrete During RainOutdoor concreting shall not be started during rain unless the Contractor has taken all protective measures including proper shelters so that the concrete maintains the slump tested at the mixing plant during transport and placing. If concreting is already in process, it shall be suspended if the rain affects the quality of concrete i.e. when the slump of vibrated concrete is 25 mm or more than the slump tested at the mixing plant for the same class of concrete.

5.8Concreting Under WaterConcrete shall be deposited in water only with the permission of the Engineer or his representative and under his supervision. The minimum cement factor of the class of concrete being deposited in water shall be increased ten (10) percent without further compensation and the slump shall be 125 mm maximum. When depositing in water is allowed, the concrete shall be carefully placed in the space in which it is to remain in a compact mass, by means of a termite, bottom-dumping bucket, or other approved method that does not permit the concrete to fall through the water without adequate protection. The concrete shall not be disturbed after being deposited. No concrete shall be placed in running water, and forms which are not reasonably watertight , shall not be used for holding concrete deposited under water.

5.9 Concrete At NightNo concrete shall be mixed, placed, or finished when the light is insufficient, unless an adequate and approved artificial lighting system is operated, and such night work is approved by the Engineer or his representative.

5.10 Concreting In Hot Weather Unless otherwise directed, when concrete is placed in hot weather and the temperature is expected to reach thirty three (33) degrees C, (ninety (90) degrees F) or higher, the Contractor shall schedule his operations to place and finish the concrete during the hours that the air temperature in the shade will be below thirty three (33) degrees C, ninety (90) degrees F); or as approved by the Engineer or his representative.

The setting time of concrete can be with hot weather very short and “cold joints” are often hard to avoid when large concreting works have to be carried out in continuous operation. To avoid cold joints, therefore, the Contractor shall provide sufficiently large capacity in his concrete producing plant and concrete transporting arrangements and use an appropriate retarder when deemed necessary by the Engineer or his representative to facilitate placing and finishing of concrete and additives to delay water evaporation. The Contractor shall use pumps for pouring concrete.

When the rate of evaporation of surface moisture from concrete is expected to approach 1 kg/m2 per hour or when the shade air temperature is expected to reach 33 degrees C and above, precautions shall be taken, including the following:

Dampening the forms which shall be painted white. Reducing the concrete temperature to the lowest practical level by procedures such as:

Shading the aggregate and cooling them by pre wetting. Cooling the water before mixing in concrete, by using appropriate and approved chilling

equipment. Screening the mixing plant and transporting vehicles from wind, rain and sun. Shielding form the direct rays of the sun all the surfaces, including reinforcement, against

which concrete is to be placed. Erecting wind breaks and sunshades at the concrete placing location. Placing concrete at night. Reducing the time between the placing of the concrete and the start of curing to the minimum

possible.


Minimizing evaporation (particularly during the first few hours subsequent to placing the concrete) by suitable means such as applying moisture by fog spraying.

All precautions to be taken shall be subject to the Engineer or his representative’s approval and the Contractor shall demonstrate that all approved precautions are available for use prior to the Engineer or his representative granting approval to any concreting operation.

The temperature of the concrete when placed shall not exceed 32 degrees C nor shall concrete be mixed or placed when the shade air temperature is 33 degrees C or above, or is expected to reach such a level during concreting, without special permission from the Engineer or his representative.

The Contractor shall provide a sufficient number of concrete thermometer for use both by his own and the Engineer or his representative’s staff.

No additional compensation will be recognized or paid to the Contractor if he has to resort to special measures, such as are described above, to control the concrete temperature.

5.11 Compacting Concrete

5.11.1 TampingAll concrete shall be thoroughly compacted to the maximum with approved tampers without any segregation in its final position before it commences to set. Care shall be taken to avoid the use of spade type tampers which may cause segregation. Initial compaction shall be with tampers and compaction with screed boards shall be limited to final shape and finish. During the placing and compaction of reinforced concrete, a competent steel fixer shall be in attendance to adjust and correct if necessary the position of the reinforcement.

5.11.2 VibratingConcrete shall be compacted by vibrating with an approved vibrator. The vibrators shall not be attached to any reinforcement or embedded fittings and where immersion type vibrators are used , care shall be taken to ensure that they do not come into contact with the reinforcement or embedded fittings. Freshly placed concrete shall not be vibrated in a manner likely to cause damage to concrete which has already began its initial set. Concrete shall not be vibrated excessively where segregation would result. Shutter type vibrators shall not be used. Nor shall immersion type vibrators come into contact with the formwork.

5.12 Curing Of ConcreteAll concrete shall be protected from the harmful effects of sunshine, drying winds, rain, flowing water, or other adverse effects. For at least 7 days after placing, the concrete shall be prevented from drying out by being sprayed with water and covered with Hessian, clean sand or other approved material which shall be kept wet.

Membrane curing of concrete with an approved liquid may be used as an alternative to curing with water except that membrane curing liquid shall not be applied to surfaces of concrete from which the shuttering has been struck, until the concrete surface and finish has been inspected and approved by the Engineer or his representative.

Concrete curing compound shall be readily upon the concrete surface for at least four hours after the application. The color, if any, shall be inconspicuous on exposed surfaces within seven days after application.

The contractor shall ensure that the concrete is adequately protected against inclement weather until properly set and shall if necessary provide additional protection to that specified above.

5.13 Inspect of ConcreteThe condition of formed surfaces shall be inspected immediately on striking the shuttering by the Contractor and Engineer or his representative, for the presence of defects. Any remedial action approved by the Engineer or his representative, such as application of cement slurry or mortar to superficial


defects, shall be carried out immediately while the concrete surface is still moist and before any curing membrane is applied.

5.14 Defective ConcreteThe Contractor shall on the written instruction of the Engineer or his representative remove and reconstruct any portion of the work which in the opinion of the Engineer or his representative is unsatisfactory as regards the quality of concrete, incorrect dimension or position of the cast concrete, badly placed or insufficient reinforcement, honeycombing or other such cause as to render the construction defective or non compliant with the specification or which may prejudicially affect the strength or durability of the construction.

5.15 Repairs To ConcreteThe method of repairing and replacing defective concrete which the contractor proposes to adopt shall be submitted to the Engineer or his representative for prior approval and the repair shall be carried out in such manner as he may direct or approve.

5.16 Supervision Of Concrete WorkThroughout the progress of the concrete work the Contractor shall employ and provide such supervision as is necessary to ensure the following;

- the day to day control of the quality of the concrete,- the mixing, transporting, placing, compacting, curing and protection of the concrete,- the testing of concrete and material constituents specified,- investigation of defects as required by the Engineer or his representative,- preparation of all concreting records and reports as required by the Engineer or his representative.

5.17 Finishing Of ConcreteAll concrete surfaces not formed by shuttering shall be trowelled to a smooth dense surface with the minimum of cement and fine particles being brought to the surface and shall be free from irregularities.

Shuttered surfaces of concrete may be formed by casting against sawn timber. All other exposed concrete including pre-cast concrete shall be cast against steel, plywood or planed timber formwork and shall be carefully rubbed down with carborundum to remove all imperfections and irregularities.

5.18 Design And Construction Of FormworkForms shall be used whenever necessary to confine the concrete, and shape it to the required lines, grades and dimension shown on the Drawings. Forms shall have sufficient strength to withstand the pressure resulting from placement and vibration of the concrete, and shall provide concrete surfaces conforming to the requirements of the finishes specified in concrete pavement. Forms shall be sufficiently tight to prevent The loss of mortar from the concrete. Where re-used forms are used, the original strength, rigidity, tightness and surface smoothness of the forms shall be maintained throughout their usage.

The Contractor shall submit to the Director or Works or his representative, for approval prior to the start of any concrete construction, the detailed design he proposes to adopt for form work, but approval of the Drawings shall not relieve the Contractor of his responsibility for their adequacy. The Contractor is advised that is recommended that form work be fabricated by a specialist supplier but in any case form work, wherever manufactured must be fabricated in a controlled environment facility.

The form surfaces in contact with the concrete will be treated or protected to avoid chemical reactions in or discoloring of the concrete surface.

The use of forms with bruises, irregularities and encrustations shall not be permitted.

Should any of the elements show signs of deformation during the pouring, they shall immediately be replaced, in order to guarantee the perfect outcome of the work.


The Contractor shall be responsible for the calculations and designs for the form work and if required, shall submit them to the Engineer or his representative before construction. On form work to external faces which will be permanently exposed, all horizontal and vertical form work joints shall be so arranged that joint lines will form a uniform pattern on the face of the concrete. Where the Contractor proposes to make up the form work from standard sized manufactured form work panels, the size of such panels shall be approved by the Director or Works or his representative before they are used in the construction of Works. The finished appearance of the entire elevation of the structure and adjoining structures shall be considered when planning the pattern of joint lines caused by form work and by construction joints to ensure continuity of horizontal and vertical lines. Adjacent panels of form lining shall be so placed that the grain of the wood will be in the same general direction (all horizontal or all vertical).

Form work shall be provided for the top surfaces of sloping work where the slope exceeds fifteen degrees from the horizontal (except where such top surface is specified as spaded finish) and shall be anchored to enable the concrete to be properly compacted and to prevent flotation care being taken to prevent air being trapped.

Opening for inspection of the inside of the form work and for the removal of water used for washing down shall be provided and so formed as to be easily closed before placing concrete.

Before placing concrete, all bolts, pipes or conduits or any other fixtures which are to be built in shall be fixed in their correct positions, and cores and other devices for forming holes shall be held fast by fixing to the form work or otherwise. Holes shall not be cut in any concrete without the approval of the Engineer or his representative.The support form shall be such that no deflection occurs under the weight of wet concrete or other loads.

5.19 Spacing Blocks And Temporary TiesInternal spacing blocks and construction ties shall be avoided as far as possible and practicable. Where it is intended that these shall be removed whether before or after the concrete has set, the making good of the concrete shall be subject to the Engineer or his representatives approval. The removal of the blocks or internal ties must not jeopardize the stability of the construction. If, with the approval of the Engineer or his representative, these are allowed to remain in the concrete then they shall be of a material and quality that they do not prejudice the strength of the work. Concrete spacing blocks shall be made of concrete at least equal in quality to the main concrete. Metal ties shall be positioned such that they do not come into contact with any of the reinforcement or fittings and no part of the tie shall be permanently embedded in the concrete nearer than 5 cm to the exterior surface of the concrete. All holes resulting on the concrete surface from their removal shall be in filled with 1 :2 cement mortar.

5.20 Preparation For ConcretingImmediately before the concrete is deposited, the formwork, shall be thoroughly cleaned out and freed from sawdust, shavings, wire cuttings, dust, sand, soil and all other deleterious and extraneous materials. Temporary openings shall be provided in the formwork to facilitate this work. The internal surfaces of the formwork shall, immediately prior to final erection, be coated with mould oil. The mould oil shall be of approved type and shall be applied uniformly and the quantities used shall be the minimum consistent with its purposes. The contractor shall ensure that all steel reinforcement and adjoining concrete surfaces are kept free of mould oil.

5.21 Approval Before ConcretingThe Contractor shall in all cases request the approval of the formwork by the Engineer or his representative in sufficient time to allow an inspection to be made and shall not commence concreting until such approval is obtained. The period between the Contractor’s request for approval and his intention to commence concreting shall be not less than 24 hours.

Such approval shall not absolve the Contractor of his responsibilities under the Contract.

5.22 Removal Of FormworkThe removal of the forms shall be carried out when the concrete has reached a sufficient strength, except where shorter time is approved by the Engineer or his representative.


The minimum time which shall elapse between the completion of concerting and removal of the forms shall be established by the Engineer or his representative for any particular structure, according to the design calculations. After authorization for removal, the forms shall be removed as soon as practicable, to avoid delay in specified curing of concrete, and also to enable the earliest practicable repair of surface imperfections. Methods of forms removal likely to cause over stressing of the concrete, or injury to the concrete surface, shall not be used. Forms and their supports shall be removed in such a manner as to allow the concrete to take the stresses due to its own weight uniformly and gradually.

Unless otherwise directed by the Engineer or his representative, forms shall remain in place for the following specified periods of time:

1. Arch Centers Fourteen (14) days2. Centering under beams Ten (10) days3. Floor slabs

Less than three (3) meter span Seven (7) daysMore than three (3) meters & less than six (6) meter span Fourteen (14) days

More than six (6) meters & less than fourteen (14) meter span Twenty one (21) days

4. Columns, walls, sides of beams, and other vertically formed surfaces shall be removed at an early date, as directed by the Engineer or his representative to facilitate finish and proper curing.

In any case removal of form works shall have to be carried out only after the concrete has reached a strength of 75% of the one required in the Specifications.

If high strength cement is used, the time limits may be decreased as determined by the Engineer or his representative. Special notes on the plans relative to the removal of forms and false work under arches, continuous spans and other special structures shall have precedence over the above time limits for removal of forms and false work.

5.23 Blinding ConcretePrior to placing any structural concrete on natural surfaces, a blinding layer of class C concrete shall be laid to a minimum of 75mm thickness. This blinding layer shall be suitably cured prior to subsequent concrete placement. The blinding shall be clean and free from any dust and impurities prior to subsequent concrete placement.

5.24 Concrete Below GroundAll concrete placed below ground level shall be painted with two coats of bituminous paint membrane. The expansion joints underground should be filled with rubber.

5.25 Reinforced SteelAll the reinforcing steel shall be fusion bonded epoxy coated and it shall comply with the requirements of Palestinian Standard and as specified hereinafter. Only fusion bonded epoxy coated reinforcement steel will be accepted. No other means of epoxy coating will be approved.

5.25.1 MaterialsReinforcing steel shall be High Bond, High Tension, Deformed bars having the following characteristics. (Palestinian Standard).

Minimum yield point 4,218 kg/cm2

Minimum ultimate tensile strength 6,327 kg/cm2

5.25.2 Reinforcement Steel FixingPrior to concreting the Contractor shall ensure that all reinforcement bars are entirely free from loose mill scale, loose rust, oil, grease, paint, mould oil, and all other deleterious and extraneous material. All hooks, bends and shape codes for bar bending schedules shall be to PS 52, or equivalent to be approved by the Engineer or his representative. Bars shall be bent to the correct radius around proprietary mandrels of the requisite diameter.


All bars to be fixed shall be so positioned to provide the specified cover of concrete. The steel reinforcement bars shall be fixed with tying wire to form a rigid cage.

Reinforcement projecting from the framework for continuation shall be adequately supported throughout concreting and shall not be sent out of p.

The Contractor shall in all cases request the approval of the steel fixing by the Engineer or his representative in sufficient time to allow an inspection to be made and shall not commence concreting until such approval is obtained. The period between the Contractor’s request for approval and his intention to commence concreting shall be not less than 24 hours.

Such approval shall not absolve the contractor of his responsibilities under the Contract.

5.25.3 SubmittalsThe Contractor shall submit the following in advance of fabrication:

a) Shop DrawingsBefore ordering reinforcing steel the Contractor shall submit bar bending schedules for reinforcing steel prepared in accordance with BS 4466 showing layouts, bending diagrams, assembly diagrams, dimensioned types and locations of all bars laps and splices, and shapes, dimensions, and details of bar reinforcing and accessories. Layout plans for bar supports and chairs, with typical details shall be included. Engineer or his representative review and approval of shop drawings will apply to the size, locations, and types of bars, and dimensions of bar lap splices only. Dimensions shown on the shop drawings are the responsibility of the Contractor and the Engineer or his representative’s approval of shop drawings shall not constitute approval of dimensions thereon.

b) SamplesRepresentative samples of all reinforcing steel that the Contractor proposes to use in the Works must be submitted, before Work is commenced, to the Engineer or his representative for his written approval, together with manufacturer’s certificates stating clearly for each sample the place of relevant details of composition, manufacture strengths and other qualities of the steel. In the event a reinforcing steel sample under test fails to meet the Specifications requirements at any time, or the Engineer or his representative considers that samples which were presented to him for test were not truly representative, or if it becomes apparent that reinforcing steel which has not been approved has been used on the Works, then the Engineer or his representative may instruct the Contractor to break out and remove completely all such sections of the Work already constructed using such suspect reinforcing steel.

All testing of reinforcing steel bars shall be carried out in accordance with Palestinian Standard

5.26Cement Mortar And GroutMortars and grout shall be composed of Portland cement and sand in the following proportions;

Quality Portland Cement SandG1 1 1G2 1 2G3 1 3

The amount of water added shall be sufficient to make the mortar or grout workable, consistent with its purpose.

5.27Ready Mixed ConcreteThe use of concrete delivered to the site in a plastic condition ready for placing in its final position shall be permitted provided that the constituent materials and the concrete mix shall comply with the requirements of this specification and subject to the following conditions;

- Water shall only be added to the mix under the control of the central batching plant,- No further addition of water shall be permitted,


- Dry batching with water added on site shall not be permitted,- The Contractor shall submit details of his proposed supplier to the Engineer or his representative for approval including copies of all specified current materials test certificates plus copies of batching plant and dosing meter calibration certificates,The Concrete shall be placed in its final position within 1 hour maximum of the time of adding cement to the wetted aggregates.

The contractor shall provide one copy of the delivery ticket number together with a record of the slump test on site, times of placing, completion time of placing, position of placing plus the works test cube reference number. If necessary the site test cube results should be capable of being compared with the central batching plant cube results.

5.28Concrete Spacing Blocks 1. Concrete spacing blocks shall be used to ensure correct placing and cover of the bars.2. The cover to reinforcement between the outside of the bars and the concerts face shall be : 40mm ±5mm.

5.29Water Stops Water stops are generally performed strips of durable impermeable material which are wholly or partially embedded in the concrete during consideration so as to span across the joint and provide permanent water tightness movements and for preserving water tightness. It is important to ensure that proper compaction of the concrete against the water stop is practicable. The water stop should be sufficiently wide to ensure the water tightness, and it not be allowed the water stop moving during concreting; in wall joint, water stops of the fully embedded type should be placed centrally in the thickness of the concrete and the wings or end bulbs should be supported by some form of tying to adjacent reinforcement. The distance of the water stop from the nearest exposed concrete face should be not less than half the width of the water stop. The full concrete cover to all reinforcement should be maintained. Centrally-placed water stops should not generally be used in a flat horizontal position such as in a floor slab joint. If this is unavoidable care should be taken to ensure full compaction of concrete under the water stop. With slabs, the 'under-slab' partially embedded type is preferable.

The Contractor shall submit with his Tender a detailed description of the water stop he intends to use, accompanied by a drawing showing the shape and size of the water stop, the name of the manufacture, and the methods to be installing and splicing the water stop, which shall be in accordance with the requirements detailed below.The Contractor shall also furnish all labour and materials for making field splices in all water stops. The Contractor shall take suitable precaution to support and protect the water stops during the progress of the work and shall repair or replace any damaged water stop.The rubber water stop shall be fabricated from a high-grade, tread-type compound. The basic polymer shall be natural rubber or a synthetic rubber. The material shall be compounded and cured to have the following physical characteristics: yield strength 10.2 N/mm2, elasticity of 400% at braking strain.

The design of the structure should generally provide for the continuity of the water stops system across all joints particular between floor and wall systems. The correct procedure for making the running joints on site using heat fused butt joint for PVC, vulcanized or pocketed sleeve joints for rubber and braised or welded lap joints for copper or steel must be adopted. Intersections and special junctions such as arise between rubber and PVC should be prefabricated it sealing compounds. Joint sealing compounds are impermeable ductile materials which are to provide a watertight seal by adhesion to the throughout the range of joint movement, which a have been in common use for this purpose usable teen based on bitumen or coal-tar pitch without filler such as limestone or state dust, asbestos rubber.

The sealing compound is usually applied in the surface of the concrete along the. The actual minimum width will depended on the known characteristics of the material. In floor joints of the expansion type the sealant is supported by the joint filler. The sealing of floor joints is generally quite successful since retention of the material is assisted by gravity and in many sealing can be delayed until just before the reservoir is put service so that the amount of joint opining subsequently to be accommodated is quite small. The chase should not be too narrow or too deep to hinder complete filling. Here again, a wider joint demands a smaller percentage distortion in the material.


Vertical joints in wall should be primed where necessary and they sealed on the water face with bituminous putty or other approved sealant. A suitably shaped chase should previously have bed formed. Cold-applied two-component sealing compounds based on polysulphide rubber complying with BS 4254 may be used in vertical joints in walls and generally in expansion joints because of their non-slumping properties and greater extensibility. Most sealants should be applied in conditions of complete dryness and cleanliness.

5.30Expansion Joint Finishing.the material should be un-shrinkageble mastic sealant for wastewater, polystyrene sheets of 12cm height and 2.50cm thickness.


6. MASONRY WORKS6.1General

Generally, the blocks used shall be of local manufacture made with cement and sand in approved vibrated pressure machines. The fine aggregate to be used for blocks shall be clean and sharp. It shall be chemically and structurally stable and shall comply with the Table of Gratings given here under. The cement, fine aggregate and water to be used for blocks shall comply with the requirements given under Concrete Works; and the methods of measuring and mixing the materials shall be the same. The following Mixing Table shall be strictly adhered to in all cases: -

MIXING TABLENominal Cement SandMix Kilos Cu. Meters

360 1.0

TABLE OF. GRADING – PERCENTAGE PASSINGSIZES - % PassingBS ApproximateSieve No. Inches Millimeters Sand - 3 95-1007 .095 2.4 80-10014 .47 1.2 60-10025 .24 .6 30-10052 .012 .3 5-65 .006 .15 0.15

Note: The above figures represent the limits of percentages (by weight) passing sieves of the sizes mentioned.

The blocks shall be hard, sound, square and clean with sharp well-defined arise sand shall be approved by the Engineer. Hollow blocks, where required, shall be of similar quality and overall size to the said blocks, and shall be of local manufacture made with cement and sand in approved vibrated pressure machines. The design of the cavities and webs shall be submitted to the Engineer for approval before manufacture. The thickness of the membranes or solid portions of hollow blocks shall be not less than 4 cm. each and the combined thickness of the solid portions shall exceed one third of the total thickness in either horizontal direction. Immediately after molding the blocks shall be placed on clean, level, non-absorbent pallets. Blocks shall not be removed from the pallets until inspected and approved by the Engineer. Blocks shall be cured by being kept thoroughly wet by means of water sprinklers or the approved means for a period determined by the Engineer, but in all cases for not less than three days. Blocks must not be left on earth or sand during the curing process. Blocks shall be stacked in honeycomb fashion. Solid stacking will not be permitted.The average compressive strength of solid blocks shall be not less than 45 kg.lcm2 of gross area at 28 days (average of 12 blocks) such that minimum crushing strength of individual block is not less than 85% of required strength.The average compressive strength of hollow blocks shall be not less than 35 kg.lcm2 of gross area at 28 days (average of 12 blocks) such that minimum crushing strength of individual block is not less than 85% of required strength.

6.2MortarsThe sand to be used for mortar shall be clean sharp. It shall be chemically and structurally stable and shall comply with the Table of Grading below. The lime to be used mortar shall be imported hydrated lime complying with Class B of British Standard No.890. Where colored -mortars are required these shall be obtained either by the use of colored cement or by addition of pigments complying with British Standard No.1014. The cement and water to be used for mortar shall comply with the requirements given under Concrete Works. The methods of measuring and mixing shall be the same. The following Mixing Table shall be strictly adhere to in all cases: -

MIXING TABLECement/Sand 1:4 Cement Kilos 361 Sand Cubic Meters 100 Imported Lime (Dry

Hydrate) Kilos1:4 Imported Lime with 10% Cement (1:10:2 ½) 145

---Mix

161Normal


TABLE OF GRADINGS - PERCENTAGE PASSINGSIZES SandPS Inches Approximate forSieve No. Millimeters Mortar- 5 95-1007 .095 2.4 80-10014 .047 1.2 60-10025 .024 .6 30-10052 .012 .3 5-65100 .006 .15 0-15

Note: The above figures represent the limits of percentages (by weight) passing sieves of the size mentioned.

The mortar generally shall be cement and sand (1:4) mix. Where plasticiser is added to the mortar the following mixes shall be used: - (a) Building mortar - cement and sand (1:6) and (b (Mortar for pointing - cement and sand (1:3) the palsticiser for jointing-cement and sand (1:3) the palsticiser shall be used strictly in accordance with the manufacturer's instructions. All mortar shall be used before the mitial set has begun. Mortar shall not be re-mixed after the initial set has taken place. The full description given under Section 1 Plaster-work shall apply also to the measuring, mixing, etc. of mortar for Block work.

6.3ConstructionAll block work shall be set out and built to the dimensions shown on the Drawings. Walls shall be carried up regularly without leaving any part more than one meter lower than another unless the permission of the Engineer is first obtained. In the case of cavity walls both thickness shall be carried up more than about 40 cm. in advance of the other. The courses of block work shall be properly leveled. The perpendicular joints shall be properly lined and quoins, jambs and other angles plumbed at the work proceeds: All walls shall be thoroughly bonded in accordance with the best constructional practice and as directed by the Engineer. Broken blocks shall not be used except where required for bond. All cement and sand blocks shall be soaked with water before being used and the tops of walls left off, and concrete elements in touch shall be wetted before work is recommenced. The faces of walls shall be kept clean and free from mortar droppings and splashes. All blocks shall be properly spread with mortar before being laid and all joints shall be thoroughly flushed up solid through the full thickness of the wall at each course as the work proceeds. For block walls the gauge shall be ten courses to 210 cm. Walls to be left unplastered shall have a fair face consisting of selected blocks pointed with a neat weathered or flush joint as the work proceeds using the same mortar mix as for the jointing. Walls to be plastered shall have the horizontal joints raked out to a depth of 11/2 cm. to form a key. Block work shall be bonded to concrete columns by using non-ferrous metal ties east in concrete of type and dimensions approved by the Engineer.

Cavity walls shall be built to the dimensions shown on the Drawings and the two thickness shall be bonded together with wall ties spaced one meter apart horizontally and approximately 40 cm. apart vertically and staggered. Extra ties shall be provided at reveals, quoins and openings.

The ties shall be of the butterfly twist type of No.10 S.W.G. mild steel wire zinc coated and similar to those described in British Standard No. 1243. The length of the ties shall be approximately 8 cm. less than the total thickness of the wall. The cavity shall be kept clean by lifting screeds or other means approved by the Engineer and shall be left clean at completion. Allowance shall be made for leaving, temporarily; open courses immediately under all structural members built into the walls. These open courses shall be left in suitable positions to permit the structural members to take up their full deflection. The members have been fully loaded and before the completion of the Works.

6.4LaborsArches shall be constructed in purpose-made cement and sand (1:5) mix solid blocks as appropriate to the sizes shown on the Drawings. The Contractor shall provide and erect temporary centering of


timber construction and easy, strike and remove on completion. The Contractor shall cut and fit block work around steel work etc., leave or form chases for edges of concrete slabs, Staircases, ends of partitions etc., cut chases for pipes, conduits etc., and make it good. The Contractor shall build all overselling courses, corbels, etc., where shown and build in or out and in ends of sills, steps, lintels, etc., required. Wooden plates and doors and windows frames shall be bedded and exposed edges pointed in mortar and fixing cramps shall be built in. Metal windows shall be bedded in mortar and exposed edges pointed in mastic. Fixing legs shall be built in and channels and frames grouted with mortar. The Contractor shall perform all cutting away and making good for all trades.

Expansion joints as shown on the Drawings or as directed in the Particular Specification shall be constructed generally as either:a) Open expansion joint with a clean straight cavity of the width directed.b) Joint filled with an impregnated fiberboard of the thickness directed.


7. PAINTING AND PROTECTIVE COATINGS

7.1GeneralPainting and coating materials shall be as specified. The amounts used, and the application, shall be in accordance with manufacturer’s instructions, including surface preparation (cleaning, sealing, roughing, etc…), and shall be subject to the prior approval of the Engineer or his representative.

If the painting and coating are not executed as specified, the Contractor shall, at his own expense, remove the paint and thoroughly clean the area, in accordance with the instructions of the Engineer or his representative. Only after receiving the approval of the Engineer or his representative, the Contractor shall apply the painting or coating once again (and in accordance with the Specifications).

All concrete surfaces to be painted shall first be thoroughly prepared, including cleaning, smoothing, filling-in, etc. Prepared surfaces shall be free of dirt, oil, grease and other foreign matter, and shall be completely dry.

7.2Interior AreasThe interior walls, floors and roofs of the valve chambers, pump wet pit , distribution chamber and the manholes, shall all be painted with epoxy paint first class after receiving the approval of the Engineer or his representative, at least 2 layers and until a uniform color is attained.

7.3Exterior AreasThe exterior berried walls of the valve chambers, pump wet pit, distribution chamber and the manholes, shall all be painted with hot bitumen emulsion, on concrete, in at least 2 layers and until a uniform color is attained.

7.4MetalworkAll metal items coming into contact with the wastewater, whether inside or outside of a structure or building, shall be Stainless Steel. Items not coming into contact with the wastewater shall be painted with special epoxy paint.

8. METALWORK

8.1LaddersLadders shall be as specified in the Drawings and the Bill of Quantities. Stainless Steel ladders shall be used. Payment shall be per meter length, including supply, erection, and all required works.

8.2Hand Rail

The Contractor shall erect on top of the walls of the parapet of the pump pit and distribution chamber Stainless Steel hand rail, as per the Drawings.

Payment for this work shall be per meter and shall include supply of the anchoring plates and the profiles, all welding and connection works, and all requirements indicated in the Drawings.

8.3CoversCovers shall be as per standard drawings, and requirements as specified in the Bill of Quantities and Drawings. Covers shall be galvanized and painted. Price shall be per unit (as per its dimensions), including supply, erection and all other necessary works.


9. PROTECTIVE COATING, LINING And PAINT WORK Unless otherwise specified, the protective coatings, linings and paint-work described in this Sub-clause shall be applied, as directed in this and other Sub-clauses of this Specification, to all metallic items supplied in this Contract. To permit future repairs of items supplied, the Contractor shall furnish the Employer with one (1) gallon each of all coatings, linings and paints (both primer and cover paints) used for equipment supplied. The cost of these coatings, linings and paints shall be included in the tender price of the equipment to be supplied.

All equipment supplied and delivered to Site under this Contract shall be inspected by the Engineer or his representative, and any equipment found to have defective or damaged coatings, linings or paint-work shall be repaired or replaced as per the decision of the Engineer or his representative by the Contractor supplying the equipment.

The contractor may suggest equivalent alternative materials to those specified in this Tender, but prior approval by the Engineer or his representative shall be required in all cases. If the applied coating, lining or paint-work is not as specified or approved, the Contractor shall be required, at his expense, to remove it (to the satisfaction of the Engineer or his representative) and to replace it with a coating, lining or paint meeting the requirements of this Specification.

9.1Hot-Dipped Zinc Galvanized CoatingThe following items shall be supplied with a hot-dipped Zinc galvanized coating: all metallic items in the general sewage/sludge atmosphere (such as control panels, guardrails, and covers), other items as indicated in this Specification.

Items to be coated in this way shall be made of what is commonly known as “galvanization - suitable” steel: the content of carbon in the steel shall be less than 0.3%, and of phosphorus, less than 0.2%. The zinc shall be at least of GOB (Good Ordinary Brand) quality, containing no less than 98.5% pure zinc. The zinc bath shall contain no more than 0.03% aluminum.

The design of items to be supplied with a hot-dipped zinc galvanized coating shall take into consideration the requirements of this coating process with regard to maximum permissible size, the need for the molten zinc to be able to flow freely on all internal and external surfaces to be coated, the requirement that no sealed empty spaces be immersed in the bath, and the requirements that the item undergo cleaning, a caustic acid bath, flux treatment, and immersion in a molten zinc bath of 450C and higher.

Prior to application of the coating, the surfaces of the item to be coated shall be prepared , except that sandblasting may not be required in all cases and may be eliminated upon the recommendation of the coating manufacturer, subject always to the Engineer or his representative’s prior approval the coating shall be continuous and without defects. The coating shall be tightly bonded to the metal substrate, such that no peeling or other defects occur during movement, transport, installation or usage of the product.

Testing of the hot-dipped zinc galvanized coating shall be conducted at the factory application site prior to shipment of the coated items. The shall make such arrangements as are necessary to permit him access to the items during all stages of the galvanization process, and to be aided in the testing of those items.

Documentation attesting to the application of the coating as per the requirements of this section shall be furnished with all galvanized items supplied under this Contract, and at the time of delivery to of such items.

9.1.1 Painting Of Galvanized SteelThe external surfaces of all galvanized steel items shall be painted. Before painting, the surfaces to be painted shall be prepared after due consultation with the paint manufacturer and the galvanized steel supplier to ensure that no damage is done to the galvanized coating.

As with all painting operations, the surfaces to be painted shall be completely cleaned and then washed with clean water. Care is to be taken in the use of any soaps or detergents which may interfere with the adhesion of the paint to the metal. Oil and grease shall be cleaned with a strong


thinning agent, preferably the solvent “Erdrox 551-G”, manufactured by “Chimeras”, or equivalent.

9.2Epoxy PaintSelected items shall, where so specified, be painted with an epoxy paint. The surfaces of such items shall be prepared as per Clause 8.1. Four coats of epoxy paint shall be factory-applied to these items, with the application of each layer followed by appropriate oven heating. Each coat shall be of at least 30 microns dry thickness. The first two layers shall be an epoxy-based primer. The top two layers shall be an epoxy-based cover paint.

9.3Painting ScheduleAll exposed pipe and other equipment shall be painted according to the following schedule by the Contractor supplying them.Additions to this schedule will be provided by the Engineer or his representative at a later date.

- Orange: dangerous parts of machines or energized equipment and flammable gas lines.

- Blue: potable water- Jade Green: no- potable process or flushing water.- Brown: wastewater.- Red: fire protection equipment.

Exposed piping will be painted with arrows showing the direction of flow in the piping, and with signs (with white Arabic lettering) painted on the pipes showing the destination of the flow. Signs shall be placed for maximum convenience of viewing and at intervals of no more than 4 meters in any one room. For ease of viewing, signs on adjacent pipes (whether horizontal or vertical) shall be lined up so that they all begin on a common plane.

The cost of the paint-work and the signs described in this sub-clause shall be understood as included in the tender price of the pipes erected. No additional payment will be made to any contractor for the paint-work and sign work described herein.

9.4Corrosion Protection and Surface Coatings

9.4.1 9.4.1 Materials

a) Corrosive EnvironmentsCorrosion protection systems and surface coatings shall in all cases be suitable for exposure to their contact environmental conditions which may include any or all of the following:-

1. The climatic conditions prevailing in the project area with particular emphasis on temperature variations, high surface temperatures and high humidities.

2. Septic sewage with a pH value of unity.3. Sulphuric acid solution in sewage slimes in concentrations up to 15 % by weight.4. Hydrogen sulphide and other gases emanating from sewage, septic sewage and sewage

sludge's.5. Saline groundwater with high sulphide contents both below the water table and in soil

zones above the water table where capillary action and the presence of oxygen may cause extremely severe conditions.

6. Wind blown chlorides.7. Wind blown abrasive sands.

b) PaintProtective and decorative paint systems including primers and undercoats shall be obtained ready mixed for use. All containers of paints and other coating systems shall show date of manufacture, shelf life and pot life where applicable.


The contractor shall only be allowed to use paints which are delivered to the site in sealed cans or drums bearing the name of the manufacturer and properly labeled.

Tints and shades of final coats shall be advised by the Engineer or his Representative.

c) Impervious Tanking MembraneMembrane used for tanking to concrete structures shall be impervious, self-adhesive and covered with a release agent.Rubber bitumen/PVC membrane shall have a minimum bitumen thickness of 1.5 mm and PVC thickness of 0.3 mm.

d) PVC Sheet Lining MaterialsPVC sheet materials to be used for lining concrete structures and pipelines internally shall be manufactured from polyvinyl chloride, plasticisers and pigments to make permanently flexible sheets.

The color of the sheet shall be approved on site.

The PVC sheet shall have a minimum thickness of 1.5 mm and shall be formed by extrusion to have on one side locking keys or ribs of either T or diamond section at centers not greater than 75 mm. It shall be capable of forming a continuous 100 % effective seal with the use of welding strips or other approved method and shall be supplied with all materials and tools for making the joints.

The tensile strength of the material shall be not less than 17000 kN/m2.

All weld strips, patches and other sheets used in the permanent fixing of the ribbed sheet shall be of a material having the same composition as the ribbed sheet.

e) Bituminous EmulsionBituminous emulsion shall be to the approved standard and shall not contain less than 53 % of bitumen.

9.4.2 Installation

a) Protection to Surface of Concrete StructuresConcrete structures shall be protected both internally and externally where indicated on the drawings and by the methods detailed.

All protection systems shall be applied strictly in accordance with the manufacturer's instructions, two copies of which shall be included with the Contractor's application for the approval of the material, and when approved will be deemed to be part of this specification unless stated otherwise.

The permissible rate of permeation of all protection systems shall not exceed 0.0027 perm inches (ASTM, 1 perm inch = 1 gramme of water per hour per square foot (0.0929 m2) per mil (0.0254 mm) of thickness for a 1 inch (25.4 mm) difference in Hg vapor pressure on each side of a membrane.

Coatings shall not be applied at expansion, contraction or construction joints which incorporate a sealant.

The minimum of all coatings and linings shall be 0.5 mm.


1) External Buried SurfacesThe external surfaces of concrete substructures shall be protected or "tanked" by one of the following methods which will be indicated on the drawings.

(a) An impervious bituminous sheet membrane. The self adhesive lap joints shall not be less than 150 mm wide.

Where the membrane is laid on blinding concrete, the surface shall be free from sharp edges and projections. The membrane shall be protected from damage during the fixing of steel reinforcement and the pouring of concrete. Where the tanking is applied to vertical surfaces the surface shall first be painted with one coat of bitumen primer.

(b) A brush applied bituminous emulsion. The surface shall first be wire brushed and all dust and loose scale removed. Three coats of bituminous rubber emulsion paint shall then be applied. The second coat shall not be the same color as either the 1st or 3rd.

Both methods of protection shall totally enclose the substructure within a waterproof membrane to the limits shown on the drawing.

During the backfilling operation around all tanked structures the waterproof membrane shall be protected from damage by the use of fiberboard, or other approved material. 2)Internal and External Exposed Surfaces

Where exposed surfaces of concrete structures are not protected by reinforced plastic liners one of the following systems will be indicated on the drawings required.

(a) An epoxy resin, acrylic, polyester or latest paint system. The surface shall first be wire brushed and all dust and loose scale removed. An epoxy resin or other primer/sealer (for concrete and allied substrates) shall then be applied followed by coats of high build epoxy airless spray or other coatings to give a minimum thickness of 300 microns. The approved paint system must have adequate flexibility to suit the thermal movements of the concrete without cracking whilst maintaining an effective bond.

(b) A PVC sheet lining which shall be fixed such that the keys or ribs are cast into the concrete surface. The lining shall be capable of taking up the same profile as the concrete substrate as indicated on the drawings.

Site operatives for employment on this work shall be certified by the manufacturer as trained to a satisfactory standard in fixing and welding techniques.

After completion of either of the linings or systems as described in sub-clauses (a) and (b) above they shall be offered for inspection and testing. Two sets of testing equipment e.g. feeler probes and spark testing shall be provided and be maintained and available at all times for the sole use of the Engineer's Representatives.

Only linings or systems completely free from pinholes will be accepted.

b) Protective Coating to MetalworkProtective coating and surface preparation shall be to the approved standard and conform to the "Schedule of Protection Systems" given below, but only epoxy systems. Coatings shall only be applied when:

(1) The surface to be coated is completely dry.

(2) The air temperature is above 4o C.

(3) The humidity is less than 85%.


Manufactured items shall have all surface protection applied at the place of manufacture or in Palestine under controlled application conditions approved by the Engineer.

All coats of paint or other coating systems shall be purchased from one manufacturer and applied strictly in accordance with the manufacturer's instructions.

All machined, polished or bright surface whether internal or external shall be protected against corrosion and damage.

Where like metals are jointed at the works priming shall be applied prior to joining.

The mating surfaces of structural steelwork shall be sealed with litharge and glycerin during erection.

Where dissimilar metals are mated including bolts, nuts and washers, the mating surface shall be insulated the one from the other to provide protection against galvanic action.

On delivery of items to site, any defect in the protective coatings shall be made good.


10. STEEL PIPES, VALVES AND FITTINGS

10.1 General ScopeThis chapter of the specification shall apply to the construction of steel pipelines and pipe-work in valve assemblies and similar work.

10.2 Description Of PipeExcept as otherwise specified steel pipes, tees, bends and reducers shall meet the requirements AWWA standard C 200 ASTM A 139 grade B with alumina mortar internal lining 8 mm thick and three layers polyethylene coating from outside. Pipes and fittings shall be designed to withstand a sustained internal pressure of 16 bar in combination with earth loads and other external loads as shown on the drawings or required. All buried pipe and fittings shall be designed for an American Association of State Highway and Transportation officials H-20-S-16 loading plus 50 percent for impact, or equivalent DIN standard, and trench loads using a soil weight of 2,100 kg/m3 together with a sustained internal pressure of 16 bar. Earth loads shall be based on the cover over the pipe and fittings. Where greater loads are imposed upon the cover over the pipe and fittings. Because of the contractor’s operation, the pipes and fittings shall be designed for these greater loads.

10.3 Materials Quality Assurance10.3.1 Experience Clause

Materials and products incorporated in the work shall be manufactured by establishments regularly engaged in production of equipment meeting the specifications cited herein and in subsequent piping, valve, or piping appurtenance section. Manufacturing of the pipe and the application of the lining and coating shall be made at the same plant. All work shall comply with acceptable industry standard practice.

10.3.2 Factory InspectionUp to three Engineer or his representative may inspect pipe production at the manufacturer's plant. The Contractor shall notify the Engineer or his representative of the production schedule in sufficient time so that factory inspection will be made after the manufacturer has performed satisfactory checks, adjustments, tests and operations. Time of inspections and materials expenses including, but not limited to, air fare, transportation, lodging and resetting, caused by delay of the manufacturer, or failed tests, shall be borne by the Contractor through deduction in Contract price.

a) General Design Criteria: All piping, valves and accessories shall be of suitable design for the service intended. They shall be of ample strength for all stresses which may occur during fabrication, transportation, erection, testing and continuous or intermittent operation and corrosion resistant to the fluid being conveyed.

b) Hardware: All bolts, nuts, studs and washers used in the assembly of piping shall be stainless steel for sewage.

c) Flanged and connections: It is intent of this specification that valves, fittings and piping to be jointed, has compatible end connections. As various valve and fittings has differing pressure capacities, this specification calls for flanges conforming to Palestinian Standard 16.1 Class 125 bolt patterns for design working pressures of 11.0 kg/m2 and below and flanges Conforming to Palestinian Standard 16.1 Class 250 bolt pattern for design working pressures of greater than 11.0 kg/m2.

d) Pipe Supports: All exposed piping shall be adequately supported with devices of appropriate design. Where details are shown, the supports shall conform there to and shall be placed as indicated, provided that support for all piping shall be complete and adequate regardless of whether or not supporting devices are specifically shown.


10.4 Transporting And Handling Of Pipes And FittingsPipes and fittings shall not be allowed to drop, free-wheels or strike objects which will injure them. When lifting pipes or their open ends, special hooks or plates shaped to fit the wall shall be used. Chaining will be allowed on bare pipes only, wrapped pipes shall be lifted by padded straps at least 20 centimeters wide. Care shall be exercised in transporting, handling or storing pipes and fittings in order to avoid distortion, flattering, denting, scoring or any other damage to pipes and fittings and to their outer wrap and/or inner lining (if any).

10.5 Stringing Of PipesPipes of the various diameters and wall thickness shall be stung along the alignment as close as possible to their final-position. Pipes and fittings strung along the alignment shall be protected against intrusion of earth, mud, dirt and other foreign bodies, and a gist damage to the outer wrap. Pipes shall not be strewn the side of the trench where excavation material has been or is to be placed. Where necessary or as directed by the Engineer or his representative gaps shall be left in stringing in order to allow movement of vehicles or men across the alignment.

10.6 Repairs Of Defective PipesShould lamination, cracks or other defects be discovered on any pipe, or its coating or lining, the Engineer or his representative will issue instructions as to whether such defects shall be repaired or the defective part shall be cut out or the defective pipe shall be removed. Where the pipes were supplied by the Engineer or his representative, the Engineer or his representative will pay the Contractor the cost of the repairs or other extra work necessitated there by, but other repair or replacement of pipes shall be done by the Contractor at his own cost.

10.7 Welding Of Pipes10.7.1 Welding Methods

All welds shall be made by the manual shielded metal-arc method. The welding procedure to be applied by the Contractor shall be submitted to the Engineer or his representative for approval, before the commencement of the work. All weld shall be made according to the instructions of the manufacturer and to the approval of the Engineer or his representative. All welds shall be made only by welders having passed the welders qualification test. Welds will be either butt welds for planned pipe joints or fillet welds for lap joints (bell and spigot). The use of welding machines with two outlets will not be permitted; every welder shall work with a separate machine.

10.7.2 ElectrodesElectrodes used for welding shall meet the requirements of ASTM Specification A 233 as last revised. Generally, with DC generators, H610 product by Sika or HR6010 4mm product by Universal electrodes shall be used. In any event, the electrodes proposed by the Contractor shall be subject to the Engineer approval prior to their use.

Electrodes shall be stored in the unopened original containers in such a manner as to prevent absorption loss of moisture or mechanical damage to the coating. Electrodes in open containers shall be protected against moisture. Electrodes that have been damaged, become mist or otherwise deteriorated, shall be rejected.

10.7.3 Cleaning Of PipesPipe ends to be welded together shall be thoroughly cleaned of any dirt, oil, residues of paint and asphalt, and any other foreign matter that may adversely affect the quality of the weld. Paint oil residues shall be removed with kerosene or benzene.

10.7.4 Welding Of JointsThe pipe will be joined by a spigot bell welded joint. The number of beads in each weld seam hall not be less than two, and their thickness shall not exceed 3.0 mm.In fillet welds (bills & spigot joint), the thickness of the throat shall be at least (0.707) of the pipe wall thickness. Cutting back of the edge of the bell shall be kept to a minimum. All weld metal shall be thoroughly fused to the parent metal and to the previously placed weld metal.The inside of every joint is protected by Sika A.1 as a primer covered within 5 hours by Sikaflex 11Fc sealant (Polyurethane compound) which joins the adjacent mortar lining and provides for continuous protection of the inside surface of the pipe.


After the completion of each bead, the weld shall be thoroughly cleaned of all scale, slag, or dirt. All spots on the weld where electrodes are changed shall also be cleaned. A penning hammer and steel brush may be used for cleaning, provided it is done to sound and bright metal. The finished seam shall be thoroughly cleaned by means of steel brushes.

10.7.5 Welding PositionsThe welds shall be made either by roll welding or position welding. Roll welding will be permitted, provided alignment is maintained by the use of skids and roller dollies supporting two or more lengths of pipe. Position welding shall be done with the pipes resting on skids at the proper height over or alongside the trench, so as to permit completing the weld on the whole circumference. All requirements as to the quality of the welds shall apply equally to roll welding and position welding.

10.7.6 Jointing Of Line SectionsPipes shall be connected to each other by welding as specified above, while they are placed on suitable supports on the trench bottom or on the ground beside the trench.The length of sections to be welded together before lowering shall be as determined by the Engineer or his representative. The position of every pipe or elbow in the section shall be such that, when the section has been lowered to the trench bottom, the longitudinal seams will be located between the figures 10 and 2 on the clock face, so that repairs on the seams can be done in the trench without necessitating deep excavation. Before being connected to the line, each pipe and each elbow shall be cleaned on the inside.

10.7.7 Repair Of Weld DefectsThe Director for works or his representative may permit repairs of defects in the root or filler beads to be made, but any weld that shows evidence of repair work having been done without such permission may be rejected.Pinholes and undercuts in the final bead may be repaired but such repairs shall be subject to the Engineer or his representative approval. Undercuts not exceeding 1.0mm in depth will not be considered as defects.Before repairs are made, the defective areas shall be removed by chipping grinding, or flame gouging. All slag and scale shall be removed by wire brushing. When cracks are found, the entire seam shall be cut and re-welded.The Contractor shall clearly mark with oil paint on top of the pipe any defect that may be discovered in the pipe or weld.

10.8 Various Welding Work10.8.1 Cutting And Preparing Pipes For Weld

Square cuts shall be in a plane perpendicular to the pipe axis. Oblique cuts shall be done accurately to the required angle in such a manner that the cut edge is in one plane. Pipe ends for butt welding shall be beveled to an angle of 300 with the plane of the edge, with a permissible variation of +50 or -00.

All cutting shall be done with a mechanical tool, or by acetylene flame cutting by means of a special cutting device or Arc-air (carbon electrode with air jet). Flame cut surfaces shall be perfectly clean, and if this is not achieved by cutting, the cut surfaces shall be filed smooth. Cutting of mortar-lined pipes shall always be done with Arc-air cutting equipment. After the metal has been cut through to the mortar lining, the latter shall be carefully broken along the cut and pipe edge prepared for welding as required above.

10.8.2 Welding Of FlangesThe welding of flanges to pipes shall be of the same quality as that specified for pipe welds. Slip on flanges shall receive an interior weld inside the flange opening, in addition to the external weld.

Weld-neck flanges shall be attached to pipe ends as specified above for the welding together of pipes, care being taken to ensure a perfect concentric alignment between pipe and flange.

When welding on flanges, care shall be taken that the face of the flanges is perpendicular to the pipe axis. Flange faces shall be kept free from weld material or other defects such as splutter, dirt, etc. All defects in the flange faces that may interfere with the proper sealing of flanges shall be repaired.


10.8.3 Welded ElbowsThese shall consist of suitable obliquely cut pieces of pipe (“miters”) welded together. These miters shall be cut to the exact dimensions shown on the drawings and accurately fitted together s that after welding the completed elbow will have the exact shape and dimensions shown on the drawings. The ends of the miters shall be beveled for welding as specified as specified above.

In all elbows having a diameter of more that 10” the seams between miters shall also receive and internal weld pass, which shall be made after the weld root has been thoroughly cleaned.

10.8.4 Prefabricated FittingsPrefabricated elbows, tees and reducers shall be jointed to pipes by square butt welds or by welds as specified above for pip-welding, care being taken that the true alignment and correct position of the fitting are ensured.

10.9 Valves And Fittings10.9.1 Scope And Specified Gate Valves And Sluice Gates

The work includes the manufacture, testing and supply of valves, supports, hangers and all required appurtenances as shown on the Drawings. Valves should be Hacohav, ARI or equivalent approved. The Contractor shall submit all the catalogues and manuals of every valve before their installation for approval.

10.9.2 Gate Valvesa) GeneralThese specifications are applicable to all sizes of gate valves described in this section.

b) ValvesShall conform to the provisions of AWWA C500 as latest revised and as further specified herein. Valves shall be cast iron body, of the double-disc, parallel seat, non-rising stem type for under ground use. Valves shall open counter clockwise.

c) Pressure RatingThe minimum designed working pressure shall be 16 bar for valves with diameters of 300 mm and above. Valves pressure ratings shall equal the class of pipe unless otherwise indicated on the Drawings.

d) MaterialAll bronze parts other than valve stems shall conform to ASTM B62 Grade 1, except that the maximum zinc allowance shall be seven (7) percent and the maximum aluminum allowance be two (2) percent. Valve stems shall not contain more than five (5) percent zinc silicon bronze and shall have a minimum tensile strength of 400 MPa and a minimum yield strength of 220 MPa, and elongation of not less than ten (10) percent in 40 mm. Body bolts and nuts shall be cadmium plated. Body seats rings shall be Grade 1 bronze. They shall be backed, threaded, and screwed into machine seats in the body. Stem collars shall be cast r forged solid with the stems. Stems entirely engaged with the valve in closed position. The threaded length of the stem nuts shall be not less than 1-1/2 times the outside diameter of the stem. Stems and stem nuts shall be Grade 1 bronze. All wave interior ferrous surface shall be protected from a minimum thickness of 250 microns in accordance with the manufacturer’s instructions. Before application, the surface shall be sandblasted and air blown to ensure a good bond. The Contractor shall examine all bolted pats on the valve body to ensure that valve have been internally coated and tight proper to installation.

e) PackingThe packing shall be double “O” ring recessed into the grooves in the ring plate only. Grooves shall not be in the stem unless the thickness of the stem at the smallest diameter of the groove equals that of a stem required without a groove.10.9.3 Air And Vacuum ValvesThe valve shall allow air to be released and to enter the line at normal operation conditions, during filling and draining out and under water hammer conditions. Under water hammer, the valve shall allow


enough air to enter to keep the pressure close to atmospheric. The valve shall not have a quick opening-slow closing mechanism.

It shall be of 100 mm diameter and shall be supplied and installed all with necessary fittings including a stop gate valve 100mm. The valve shall be coated with anti-rust paint suitable for marine environment. It should have a flushing mechanism without the need to dismantle the valve.

The Contractor shall submit for the approval of the Engineer or his representative all catalogues and manuals of the manufacturer prior to the installation.

The work shall be in accordance with the instructions of the manufacturer and to the approval of the Engineer or his representative.

10.9.4 Installation Of Valves And Fittingsa) GeneralBefore being installed, the valves and fittings, and specifically valve sets shall be cleaned of any dirt that may have entered them. When installing the vales, their correct position shall be ensured by means of a spirit level . Fitting the valves to pipes shall be done accurately, but without using force. Fitting of valves by tightening bolts forcibly or by any other method that will case internal stresses in the valve or flanges will not be permitted.

b) FlangesFlanges shall be welded to the pipes in accordance with the requirements of subsection 12.8.2 . Care shall be taken to weld the flange with the face perpendicular to the pipe axis and the bolt holes straddling the center line. Flange faces shall be kept free from weld material, spatter, and any other foreign matter, and all defects that may prevent proper sealing of flanges shall be repaired.

c) BoltsOnly bolts of the correct diameter shall be used. All bolts used on a valve shall be equal length, which shall be such that after the nut has been tightened not less than one thread and not more than three of the bolt will protrude from the nut. Bolts shall be tightened crosswise, gradually and uniformly.

d) GasketOnly one sealing gasket shall be used between each pair of flanges. Gaskets shall be of the ring type, i.e. their outer rim shall just touch the bolt holes and their inside diameter shall be equal to that of the corresponding pipe. Gasket material shall be either fabric reinforced rubber or compressed asbestos sheets known as “Klingerit”. Gaskets shall be fabricated by cutting from sheets. Cutting the gaskets by hammering on the flange will be strictly prohibited. When being installed the gaskets shall be absolutely clean. Each gasket shall be used only once.

10.10Sluice Gates10.10.1 GeneralThe Contractor shall supply and erect sluice gates as shown on the pertinent Drawings, and as specified in this Sub-clause.

The supply of all sluice gates shall include the gate slide or seat, frame, floor-stand, guide bars, wedges, stems (or extension spindles), stem guides, actuator, bearings, seals, fasteners, mounting equipment and all related and auxiliary equipment.

All gates and accessories shall operate safely, properly and with a practical degree of water tightness under the maximum unbalanced heads indicated. All parts of sluice gates supplied shall be designed to carry the strains without springing or bursting and shall have a factor of safety of not less than five times any force which may come upon the equipment under the heads and condition of use. Gates shall be designed to prevent chattering of the gate or springing of the lifting jack.

All gates shall be operated by hand-wheel lifts. Unless otherwise indicated, the horizontal axis of the hand-wheel (perpendicular to the stem) shall be approximately 90-100 centimeters above the flooring above which it is mounted. All gates shall be suitable for both seating and unseating pressures.


10.10.2 Sluice Gates Componentsa) ScopeThe Contractor shall supply circular sluice gates, according to the following schedule, the Drawings and the Bill of Quantities. All gates shall be operated from floor-stands mounted at the top concrete slabs or gratings.

Unless otherwise indicated, all circular sluice gates shall be face-mounted.

b) Construction and materials (1) Gate frames shall be of Stainless steel 316 and of adequate section to resist distortion.

(2) Wedges Side, top and bottom wedges are to be Stainless steel 316 all bearing surface fully machined, or neoprene. They must be fully and accurately adjustable and shall be provided with bronze mount bolts, adjusting screws and lock nuts. The distribution and number of wedges shall be such as to ensure proper seating of the slide under the maximum heads specified.

(3) Door, sealant and frame plate shall be made of HDPE (high density polyethylene). The stems must be furnished in sections, if necessary, to permit reasonable ease in installation and removal. All stem couplings and the thrust nut for connecting the stem to the gate are to be Stainless steel. Couplings must be threaded and bolted to the stem and provision must be made at the thrust nut to prevent stem rotation. Stop collars with set screws shall be provided to prevent over-travel in closing the gate.

(4) Thread spindle shall be of Stainless steel 316, extended to the required level of operation.

(5) Stem guides shall be Stainless steel 316. The guides shall be adjustable in two directions, to provide full adjustment for proper alignment with the stem. The slenderness ratio (L/r) of the stem shall not exceed 200.

(6) Hand wheel lifts shall be of cast-iron with anti-friction thrust bearings above, and a cast manganese bronze lift nut flange below. The bearings and nut must be lubricated. An indication of the direction of turn for either opening or closing shall be cast in a readily visible location. The maximum tangential pull at the rim of the hand wheel shall not exceed approximately 40 pounds for operation of the gates.

(7) Painting a metallic surfaces shall be prepared. Exposed machined or bearing surfaces shall be coated with a water resistant rust-preventive compound. Enclosed machined or bearing surfaces shall be coated with water-resistant grease. The exterior surfaces of the lift assemblies shall be shop painted with a machinery enamel. All other assembled units shall be given an epoxy coal tar coating. Epoxy-resin shall be applied in-situ after installation

10.11Lining, Coating And Painting Of Pipes10.11.1 External Coating On Underground PipingAll Pipe to be laid blow ground shall be protected against corrosion by the use of the following external coating.

1- Base layer of epoxy primer 80 micros thick. 2- Hand adhesive (polythyle “copolymer) 500 micros thick.3- Top coat material polythyle which contains 2% of carbon Black of thickness shall not be less than specified thickness in table below

Diameter (inches)

Up to 4 4 - 10 12 - 30 24 – 38 40 - 68

Thickness (mm)

1.5 1.8 2.0 2.5 3.5

Pipe ends to be welded shall be bare. All valves and fittings and pipe to be laid below ground shall be supplied with an anti-corrosive priming.Polyethylene coating to be done under this Contract shall include:

- Coating of weld joints- Repair of defects in factory-applied coating


- coating of primed or bare pipes, fittings, and valves.Coating applied by the Contractor shall be equal to the coating applied to pipes in the factory. Repairs and coatings of welds on coated pipes and the coating of bare pipes and fittings shall be bonded to the existing pipe coating so that a continuous uninterrupted coating over the entire length of pipeline is achieved. No joint shall be coated before the Engineer or his representative approval to proceed with coating has been given. Only qualified experienced personnel under expert supervision shall apply the coating described in this Specification.

10.11.2 Painting Of Exposed PipingThe metal surfaces of all pipes laid above ground together with valves, straps and supports as well as all steel structures shall be painted in accordance with an anti-corrosive priming. Colors of paints shall be as directed by the Engineer or his representative.

10.11.3 Internal CoatingThe internal coating of steel pipes conveying sewage is consisting of high Alumina Cement of thickness is as specified in the following table in accordance with Palestinian Standard. Welding and jointing shall be according to instructions of the manufacturer.

Nominal Pipe Size(Inch) (mm)

Lining Thickness Tolerance(inch) (mm) (inch) (mm)

4 – 10 (100 – 250) ¼ (6) -1/16, + 1/8 (-1.6, + 3.2)11 – 23 (280 – 580) 5/16 (8) -1/16, + 1/8 (-1.6, + 3.2)24 – 36 (600 – 900) 3/8 (10) -1/16, + 1/8 (-1.6, + 3.2) 36 ( 900) ½ (13) -1/16, + 3/16 (-1.6, + 4.8)

10.12 Laying Of PipelinesExcept for pipes shown on drawing or as instructed by the Engineer or his representative to be laid on supports, steel pipes shall be laid below ground in trenches.

All jointing between pipes and between pipes and fittings shall be done by welding, except that where shown on the drawings or directed by the Engineer or his representative, flanges, or mechanical couplings shall be used. Before lowering in, the pipe coating shall be inspected and all defects repaired. Lowering of pipes into the trench shall be done by pipe layers or other equipment acceptable to the Engineer or his representative, so that no injury or deformation is caused to the pipes or the coating and lining.

Welded pipes shall be laid on the finished trench bottom, so that each pipe is supported over its entire length. Where valves, or flanges or mechanical joints are to be installed, or overhead welds are to be made in the trench, the latter shall be widened and deepened by additional excavation around the pipe in order to provide working space (bell holes).

The dimensions of such bell holes hall be such as to provide convenient access and sufficient working space. Before joining each pipe to the line, a cleaning swab with a cable attached to it shall be introduced into the pipe last welded before the new pipe. When the welding to the line has been completed the swab shall be pulled forward by means of the cable through the new pipe, thus cleaning and removing all slag, metal, dirt and foreign matter which may have accumulated inside the pipe. Where pipes are large enough to be entered by workmen, said cleaning shall be done by hand.At the end of each working day and wherever work is discontinued for a considerable time, the ends of each welded section whether in or alongside the trench shall be closed by a suitable cover snapping on the pipe end. Lowering-in of pipe or replacing them on permanent supports shall be done carefully to prevent damage to pipe coating or paint. To prevent pipes from slipping out of mechanical joints or the formation of excessive stress in welds at a result of temperature changes, lowering-in of pipes and joining of sections shall be done in the early hours of the morning only.

The first stage backfill of the trench shall be done before the final teeing welds or bolted connections (in the case of mechanical joints or flanges) are made, leaving a stretch of about 20 mm uncovered on either side of such final joint.


11.WELD INSPECTION AND TESTS

11.1 Inspection And Tests - GeneralThe Engineer or his representative will exercise a continuous control of the welding work and will inspect the quality of the welds. In addition to routine supervision and visual inspection of the completed welds, the Engineer or his representative will have the right to request samples to be cut from the welds for destructive tests. If so required by the Engineer or his representative, welds shall also be tested by radiography.

11.2 Destructive Tests

11.2.1 GeneralDestructive tests will include all or part of the following, at the discretion of the Engineer or his representative:

- Break Test- Bend Test- Tensile Test (in special cases)

Both the Contractor and the Engineer or his representative will endeavor to ensure the proper execution of the welds, so as to avoid altogether or minimize the number of destructive tests.

11.2.2 Frequency Of TestShould one of the samples taken for the destructive tests not meet the standards of acceptability set out below, the Contractor will be required to cut additional samples from the same weld or from other welds made by the same welder. If one of the new samples does not meet the requirements, the Contractor will be required to cut more samples unit a clear picture of the extent of defective welds in obtained.

Should such additional tests show that the quality of the welds in unacceptable, as determined by the Engineer or his representative, the Engineer or his representative may required the Contractor to remove and re-weld all welds made by the welder concerned. In the event of the test sample meeting the requirements of the Specification, the cost of cutting the sample and preparing and testing the specimens, and that of patching the pipe where the sample has been cut out, will be borne by the Engineer or his representative. Should the sample fail to meet the above requirements, all such cost, as well as the cost of all additional tests that may be required, to determine the extent of the defective welds as aforesaid, shall be borne by the Contractor.

11.2.3 Taking Samples For Bend Test, Break Test, And Tensile TestSamples for Bend Test, Break Test and Tensile. Test shall be cut from the pipe in the forms of strips 5 cm wide perpendicular to the weld seam and extending 10 cm on either side of the weld, so that the weld will be located in the center of the sample. The opening resulting from cutting the sample shall be closed by the welding on a patch of steel plate having a thickness not less than that of the pipe wall. The cost of patching up openings as herein described shall be included in the cost of taking samples as specified above.

a) Bend Test: The bend test samples shall be bent in a suitable jig in the field or in the shop. The bend shall be located exactly over the weld with the weld face on the convex side. The sample shall be considered as meeting the requirements if it will not break and no cracks larger than 3 mm in any direction will appear on the convex side of the bend.

b) Break Test: The break test samples shall be hacksaw-notched on both edges across the center of the weld to ensure breaking of the sample in the weld. The sample shall be supported on both sides of the weld and broken by a strong hammer blow. The required result is: the broken surface shall show full penetration of the weld and no burns or excessive slag inclusions. The break surface shall not show more than one gas pocket per square centimeter, provided that no gas pocket has a diameter of more than 1.5 mm.


c) Tensile Test: Samples for tensile strength and elongation tests shall be send for testing to an authorized laboratory. These tests will serve as a control of the welding procedure and of the quality of the electrodes, but not to test the welders’ ability. In this test, the samples shall show a tensile strength not less than that required of the steel of which the pipes are made.

11.3 Radiographic TestWhere required, radiographic tests shall be performed in accordance with the Palestinian Standard Boiler and Pressure Vessel Code, Unless otherwise specified, 10 (ten) percent of al weld seams shall be radiographer.

If these primary tests should not give satisfactory results, the Engineer or his representative will conduct additional radiographic test as certain the quality of the welding work. All weld defects discovered by the tests shall be repaired as directed by the Engineer or his representative and all repaired welds shall be re-tested.

The routine radiographic tests (10 percent) will be carried out at the Engineer or his representative’s expense. Should, however, the Engineer or his representative think it necessary to conduct additional tests because of the defective quality of the welds. The cost of all such additional tests will be charged to the Contractor’s account. The contractor shall also bear the cost of repair of all welds found defective under test as well as the cost of re-testing such repaired welds.

Unless otherwise specified, the standard of acceptability for radiographic weld tests shall be in accordance with the I.W.I (International Welding Institute) standard for class “Green”.


12. HYDROSTATIC PRESSURE TEST

12.1 GENERALAfter pipe laying, casting of concrete structures on the line and partial backfill have been completed, the line shall be subjected to a hydrostatic pressure test. The line shall be tested over its entire length or, in the case of long line in section. The pressure test shall only be performed in the presence of the Engineer or his representative. The test pressure shall be determined by the Engineer or his representative in Each case. The required pressure shall be obtained by means of a special pressure pump or by connecting the line to a suitable source of pressure.

12.2 Preparations For Pressure Test

Filling of the line with water shall not begin until 6-7 days after the last concrete structures have been cast. Prior to filling the line, all joints and structures shall be inspected and the good condition and proper functioning of all valves shall be bullheaded and securely anchored. The testing installation and the working of the pump shall also be examined.

12.3 Filling The Line With WaterThe line shall not be filled until the Engineer or his representative written approval thereto has been given. The line shall be filled gradually and slowly in order to prevent water hammer or chattering in the pipe and to permit the escape of all air from the pipeline. The rate at which the line is to be filled shall be as determined by the Engineer or his representative. At the commencement of filling, all blow-out valves shall be open, and each valve shall be closed after the water has flushed all dirt that may have accumulated in the pipes. After the filling has been completed, but before the pressure is raised, all valves shall be inspected for water-tightness and all leaks in gaskets an stuffing boxes shall be stopped. Should this inspection show And leaks at the joints or defects in the valves that cannot be repaired while the line is full of water, the line shall be drained and the necessary repairs done. This inspection shall be repeated until all leaks are stopped.

12.4 Pressure TestThe pressure in the line shall not be raised until 24 hours after its being filled with water, and in any case not until the Engineer or his representative approval has been obtained. The pressure shall be increased gradually and slowly until it has reached the required height and shall be kept at such height for as long as the Engineer or his representative will determine (The pressure test value is 1.5 the pressure design value). While the line is under pressure all joints shall be checked for water tightness and any leak discovered shall be considered as a defect that has to be repaired. After the leaks have been stopped, the pressure shall be raised again and the test repeated. The tests and repairs shall be repeated until the line is absolutely tight to the satisfaction of the Engineer or his representative. The pressure test shall also serve as a strength test for the concrete structures on the line, and any defects discovered in such structures shall be required; at the Engineer or his representative request faulty structures shall be turn down and rebuilt.


13. CONCRETE MANHOLESConcrete manholes shall be constructed at the locations shown on the Drawings, and elsewhere as directed by the Engineer or his representative. Their shape and dimensions shall conform to those shown on the typical Drawings and the inner dimensions, if not specified otherwise, will be after plastering or otherwise finished surfaces.

13.1Cast-In Situ Reinforced Concrete ManholeThis type consists of a reinforced concrete (B300) base slab cast on firm ground foundations (so as to prevent any differential settlement), reinforced concrete (B300) walls cast on the base at least 24 hours later with the required openings for installation of pipes in one time or more according to the manhole depth, and reinforced concrete roof slab with the appropriate cover. Reinforcement and dimensions shall be as shown on the Drawings. The forms used shall be tight, proper and smooth. Water stop RX type or equivalent, shall be placed when the concrete cast on stages.

13.2Pre-cast Concrete ManholeThis type consists of a cast-in situ or pre-cast reinforced concrete (B300) base with the required openings for installation of pipes installed on a firm ground foundations (so as to prevent any differential settlement), precast concrete (B300) rings of 1 m height or as specified on the Drawings of tongue and groove type for the walls fixed on the base and precast reinforced concrete roof slab with the appropriate cover. Reinforcement and dimensions shall be as shown on the Drawings. The forms used shall be tight, proper and smooth.

Joints between the slabs, rings and bases of manholes shall have natural or synthetic rubber ring maintained in place in such manner as to ensure watertight joints during the specified tests and the subsequent life of the installed manholes. The rubber ring shall be highly resistant to deterioration in contact with sewage and shall be seamless and MAGNUFLEX type or equivalent.

13.3Benching, Plastering And Coatinga) Benching

Smoothly constructed U-shaped channels, to carry and direct the sewage flows, shall be formed integrally with the concrete base, or may be constructed separately by benching. The lateral height of the channel shall be as shown on the Drawings. Adjacent floor areas shall slope with 4:1 to drain to the channel with the same longitudinal gradient. All transition curves shall be smooth. The concrete used for benching shall be B300.

Pipe stubs for future connections shall be installed where shown on the Drawings or otherwise required. The stubs shall extend at least 50 cm beyond the outside of the walls of the manhole and shall be plugged watertight. Appropriate channels for the future connections shall also be prepared in the benching.

b)PlasteringWhere shown on the Drawings or otherwise required, internal surfaces (e.g., cast-in situ manholes) shall be lined or plastered with 1 cm thick cement sand mortar in the proportions 1:1½ and steel trowel finished.

The inside plastering may be omitted if steel forms are used and the inside surface of the wall is as smooth as the cement plaster finish or otherwise directed by the Engineer or his representative.

c) CoatingCoating material of 100% Solid Coal Tar Epoxy or equivalent shall be applied to the internal surface of the walls and the roof of Sewerage manholes as shown on the Drawings or otherwise directed by the Engineer or his representative.

13.4Deep ManholesThe upper ring where the depth of manhole is more than 2.5 m or as directed by the Engineer or his representative, should be of a cone shape. Concrete encasement for manhole cover shall be constructed according to the Drawings and as directed by the Engineer or his representative. Encasement should be applied where manhole laid in natural ground surface or in the gradient of


1.5% or more in paved area, the manhole neck should be encased as shown on the Drawings with reinforced concrete B300.

13.5Drop ManholeDrop manholes shall be built where shown in the Drawings. The drop shall be made by means of a pipe and related fittings like elbow and tee, of the same diameter of the pipe, all shall be located outside the manhole. The incoming sewer will have an emergency straight connection to the manhole. The outside drop should be entirely encased in a concrete block, as shown on the Drawings. Where the walls are of precast rings, great care shall be taken to assure good connection between walls and the above mentioned blocks. Appropriate openings for the drop pipe and emergency inlets should be made in the precast rings at the factory where shown on the Drawings or directed by the Engineer or his representative.

13.6Manhole Cover And GratingManhole covers shall be circular, made of cast iron or of concrete with cast iron frames, the dimensions and type conforming to Palestinian Standard, as shown on the Drawings or requested by the Engineer or his representative. Manhole frames shall be set firmly in cement mortar so that the covers are 1cm below the final surface. All manhole covers shall be non-ventilated and non rocking. All sewerage manhole covers shall have the words (SANITARY) and ( ) cast on their surface. Heavy duty type cover (25 tone bearing capacity) shall be installed in all roads, streets and highways greater than 4.0m with an opening of 50 cm or 60cm as specified on the drawings, where as openings for 5 &8 tone bearing capacity are 40 & 50cm, respectively.

After completion of the Work, cast iron parts of the covers and the frames shall be painted with bitumen paint. Grease shall be placed between the frame and the cover.

Unless otherwise indicated or directed, concrete roofs and cast iron covers and frames shall have the following bearing capacity:

a- Heavy duty cover and frame shall withstand a load of not less than 25 metric tones. b- Medium duty covers and frame shall withstand a load of not less than 8 metric tones.c- Light duty cover, and frame shall withstand a load of not less than 5 metric tones.

Cast iron grating with frame shall be supplied and or manufactured in accordance with details shown on the Drawings and in accordance with the instructions of the Engineer or his representative. Frame shall be embedded in the concrete of the roof of storm water inlet and Catch basin and depressed 3cm below the final surface.

After completion of the Works, cast iron parts of the gratings and frames shall be painted with bitumen paint.

13.7Manhole Inspection a) Water absorption test

In accordance with the Palestinian Standard, the increase in the dry mass of a single test piece by absorption of water shall not exceed:

I. 3.6% after 30 minuets.II. 6.5% after 24 hours.

b) Cube crushing testTests of concrete shall be carried out in accordance with Palestinian Standard.. Preliminary tests shall be made by the Contractor to determine suitable mixes. Routine tests shall be made for cube strength with 8 cubes 100x100x100 mm of concrete from each concreting location take in such manner as may be specified by the Engineer or his representative. The first four cubes shall be tested after 7 days and if these cubes shown an average strength as specified in clause 5.3.3, below 67 percent of the required strength after 28 days; the second four cubes shall be tested after 28 days.

If the strength of the second four cubes does not meet the requirements as specified in clause 5.3.3, the cubes represent the concrete structure, shall be core tested. If the core test results do not meet the requirements, then the manhole will be rejected and removed and the Contractor shall redesign and


improve the concrete mixture. All costs associated due to testing, remedies or replacement of the failed manholes shall be at the expense of the Contractor.

c) Service load test The service load of the manholes rings tested by the three edge bearing method, shall not be less than the following:

Manhole internal diameter, mm 600 800 1000 1200 1500Service Load , kN/m 37.5 47.5 56 64 77

d) Water tightness testThe hydrostatic pressure to ensure water tightness of the manholes rings, shall not be less than the following:

Manhole internal diameter, mm 600 800 1000 1200 1500Hydrostatic pressure, bar 0.1 0.2 0.7 0.7 0.7

All costs in connection with the tests shall be at the Contractor’s own expense.

13.8Manholes Protective CoatingThe interior walls of the manholes in contact with waste water shall be painted with epoxy paint, Nitocote ET401 from FOSROC or equivalent, on concrete in two layers at least and until a uniform color is attained and as per the manufacturer’s recommendations.

13.9Safety RegulationsWhenever any work or repair/or connection to existing sewers is about to be executed, the contractor shall inspect and test such sewers for the presence of dangerous gases by means of detection torches or similar devices and shall take all necessary precautions and protective measures, which shall include, but not limited to, the following:

o before entry into a manhole, the absence of noxious gases and availability of oxygen in it must be ascertained. should any noxious gases or lack of oxygen in it be discovered, no entry shall be made until the manhole has been thoroughly ventilated with the aid of blowers. only after all gases have been removed and sufficient oxygen has been introduced, will entry be permitted, but only to personnel wearing gas masks.

o manhole covers shall be opened to ventilate pipelines for 24 hours, at least, as follows:o for work in an existing manhole: the cover of the manhole upstream and downstream of it. a

total of three covers.o for connection to a sewer: the covers of the manholes upstream and downstream of the

connections. o no entrance into a manhole shall be permitted unless at least one person stays outside the

manhole in readiness to render assistance if required.o The person entering the manhole shall wear rubber gloves and rubber knee-boots with acid

resistant soles. He shall also wear a safety harness with lifting rope, the end of which will be held by the person outside the manhole.

o persons entering the manholes deeper than 3.0m shall wear suitable gas masks.o Mechanical ventilation by blower must be employed prior to entry and throughout the work in

manholes deeper than 5.0m.o Personnel employed on work requiring entry into manholes, septic tanks, etc. shall be briefed

on the above noted safety measures and drilled in the use of harnesses, gas masks, etc.o The provisions of this section shall in no way be construed as relieving the contractor from full

and complete responsibility for the safety of his workmen and any other person who may suffer accident or injury due to the works carried out by the contractor.

13.10Permission To ProceedThe contractor must receive written permission from the Engineer or his representative before executing any of the previous described works. In all cases permission to proceed should be recorded in the works diary by the Engineer or his representative. Connection of gravity sewers to existing manholes will not be paid separately, but will be a subsidiary obligation of the contractor.


14. FINISHING WORKS

14.1Block LayerI. Quality of mix for block work and mortar to match the general masonry specifications.II. Dimensions of used blocks :- 40x20x20 cm for walling. 40x20x15 cm for walling. 40x20x10 cm for walling.

III. Curing for masonry works must be carried out for seven days.IV. Block work compression strength test after 28 days = 35 kg/cm2.V. The maximum height allowed to be built at one time is one meter (5 rows of blocks)VI. The execution of this works must be carried out according to the drawings, specifications and

engineer's instructions.

Generally the blocks used shall be of local manufacture made with cement and sand in approved vibrated pressure machines. The sand to be used for blocks shall be clean and sharp. It shall be chemically and structurally stable and shall company with the Table of Grading given here under. The cement and water to be used for blocks shall comply with the requirements given under Section 4 - Concrete Work, and the methods of measuring and mixing the materials shall be the same. The following Mixing Table shall be strictly adhered to in all cases:-

Nominal

MixCementKilos

Sandm3

Lime(Dry Hydrate) Kilos

1:4 360 1.00 as approved by the Engineeror his representative

TABLE OF GRADING - PERCENTAGE PASSING SIZES

B.S.Sieve No.

- 714 2552

Inches

.095 .47.24.012.006

Approximate Millimeters

3 2.41.2.6 .3.15

Sand for Mortar95-10080-10060-100 30-1005-650.15

Note: The above figures represent the limits of percentages (by weight) passing sieves of the sizes mentioned.

The blocks shall be hard, sound, square and clean with sharp well defined arises and shall, unless previously approved by the be 20 cm in weight. Hollow blocks, where required, shall be of similar quality and overall size to the said blocks, and shall be of local manufacture made with cement and sand in approved vibrated pressure machines. The design of the cavities and webs shall be submitted to the for approval before manufacture. The thickness of the membranes or solid portions of hollow blocks shall be not less than 4 cm. each and the combined thickness of the solid portions shall exceed one third of the total thickness in either horizontal direction. Immediately after molding the blocks shall be placed on clean, level, non-absorbent pallets. Blocks shall not be removed from the pallets until inspected and approved by the Blocks shall be cured by being kept thoroughly wet by means of water sprinklers or the approved means for a period determined by the , but in all cases for not less than three days. Blocks must not be left on earth or sand during the curing process. Blocks shall be stacked in honeycomb fashion. Solid stacking will not be permitted.


14.1.1 MORTARSThe sand to be used for mortar shall be clean sharp. It shall be chemically and structurally stable and shall comply with the Table of Grading below. The lime to be used mortar shall be imported hydrated lime complying with Class B of British Standard No. 890. Where colored mortars are required these shall be obtained either by the use of colored cement or by addition of pigments complying with Palestinian Standard. The cement and water to be used for mortar shall comply with the requirements given under Section 4, Concrete, and the methods of measuring and mixing shall be the same. The following Mixing Table shall be strictly adhere to in all cases:-

MIXING TABLESand Cement Cubic Meters Kilos 1.00

Imported Lime (Dry Hydrate) Kilos

1:4 360 1.00 -- 1:4 Imported Lime with 10% Cement (1:10:2 1/2)

145 --Mix

161

Nominal

TABLE OF GRADINGS - PERCENTAGE PASSING SIZES Sand B.S.Sieve No.

Inches

ApproximateMillimeters

forMortar

- 7 142552 100

.095

.047

.024

.012

.006

3 2.41.2.6.3.15

95-100 80-10060-10030-100 5- 65 0- 15

Note: The above figures represent the limits of percentages (by weight) passing sieves of the size mentioned.

The mortar generally shall be cement and sand (1:4) mix. Where plasticiser is added to the mortar the following mixes shall be used:- (a) Building mortar - cement and sand (1:6) and (b (Mortar for pointing - cement and sand (1:3) the palsticiser for jointing-cement and sand (1:3) the palsticiser shall be used strictly in accordance with the manufacturer's instructions. All mortar shall be used before the initial set has begun. Mortar shall not be re-mixed after the initial set has taken place. The full description given under Section Plaster-work shall apply also to the measuring, mixing, etc. of mortar for Block work.

14.1.2 ConstructionAll block work shall be set out and built to the dimensions shown on the Drawings. Walls shall be carried up regularly without leaving any part more than one meter lower than another unless the permission of the is first obtained. Work is left at different levels shall be back. In the case of cavity walls, both thickness shall be carried up more than about 40 cm. in advance of the other. The courses of block work shall be properly leveled The perpendicular joints shall be properly lined and quoins, jambs and other angels plumbed at the work proceeds.. All walls shall be thoroughly bonded in accordance with the best constructional practice and as directed by the Broken blocks shall not be used except where required for bond. All cement and sand blocks shall be soaked with water before being used and the tops of walls left off shall be wetted before work is recommenced. The faces of walls shall be kept clean and free from mortar droppings and splashes. All blocks shall properly spread with mortar before being laid and all joints shall be thoroughly flushed up solid through the full thickness of the wall at each course as the work proceeds. For block walls the gauge shall be ten courses to 210 cm. Walls to be left un-plastered shall have a fair face consisting of selected blocks pointed with a neat weathered or


flush joint as the work proceeds using the same mortar mix as for the jointing. Walls to be plastered shall have the horizontal joints raked out to a depth of 1 1/2 cm. to form a key.

14.2Roof FinishesThe work of roof finishes shall consist of the following:-

a) Hot bitumen primer coat to concrete roof slab.b) Thermal insulation.c) Sheathing membrane.

d) Sand/Cement screed.e) Roof waterproofing and U/V protection

Contractors Obligations:- The Contractor shall provide all the materials, labor and equipment etc., for this work and

shall carry out and complete the entire work of roof finishes as per specifications detailed below:-

The Contractor shall submit to the Department a five years guarantee in the form of an Insurance Policy for the roof finishes from any of the approved local Insurance Companies prior to initial takeover of the project by the Department. A specimen copy of the Insurance Policy shall be submitted before starting work on site for the approval of the Department.

The insurance policy must cover the cost of labor, plant and materials for replacement and repair of the roof finishes, water-proofing and insulation in the event of its failure or leakage during the course of five years from the date of initial handing over of the projects.

14.2.1 Specificationsa) Insulation

Polystyrene Rigid Foam BoardsContractor shall lay a layer of 5 Cm. thick rigid polystyrene boards fully bonded to primed surface of the screed or directly on the concrete slabs as specified here under.

Bonding shall be done either by hot bitumen or any other approved bonding agent recommended by manufacturer. Above polystyrene rigid boards shall comply with the following:-

Thickness : 5 Cms.Thermal conductivity at 10% mean temperature : K=0.028 W/m deg. CDensity : 32.35 Kg./m3Water absorption : 0.1% volumeCapillary : NoneCompressive strength at 5% Compression : =0.245 M/N/M2

There shall be no air between screed or concrete slab and polystyrene board.

Polyurethane Foam:3 Cm. thick (minimum) polyurethane foam sprayed in 3 layers each 1 cm. thick over cement/sand screed laid to fall (1%) over the primed surface of the concrete roof slab. It shall consists of the following:-

1 part 'Plyol' and 1 part 'Isocyanate' mixed as recommended by the manufacturer and approved by the .

Mixing Proportions : 1/1 Density : 60 Kg./m3 Tensile strength : 5.0 daN/cm2 Compressive strength : 3.5 daN/Cm2 Water absorption : 59 gr/M2/24 hours Thermal conductivity : 0.021 W C


Rigid Mineral Wool Slab:-Rigid mineral wool slabs shall be bonded to the primed surface of concrete slab. The rigid mineral wool slabs shall comply with the following:-

Thickness:8 Cms. thick faced with aluminum foil on one side.Non combustibles and water repellent.

Density:120 Kg/m3Thermal conductivity coefficient 'K' value at 10 C shall not be more than 0.031 w/m deg. C. It shall be fully bonded to concrete roof slab with hot bitumen or the approved/recommended bonding agent.

b) Sand/Cement Screed:(A base for waterproofing treatment or thermal insulation)

Minimum 3 Cm. thick sand/cement screed layer - 1 part cement to 4 parts clear sand shall be laid to fall 1% or as specified on the drawings, over the concrete roof slab or the roof thermal insulation depending on the types of roof finishes specified here under. Maximum thickness of the screed shall be 10 cm.

Sand used for the screed shall be clean natural and, free of all salts and other impurities, graded passing through a 4.76 mm. British Standard sieve with a good proportion of larger particles.

Cement shall be Portland cement complying to Palestinian Standard for ordinary and rapid hardening Portland cement.

c) Waterproofing:Two coats of Elastomeric Acrylic Paint

Diathon or similar approved waterproofing and ultraviolet ray's protection shall be applied over the polyurethane foam. First coat shall be gray color with fiber glass mesh reinforcement bonded to the insulation surface. The second top coat shall be white color applied perpendicular to the first coat. Total thickness of the coat shall be 609 dry microns (excluding fiberglass mesh). The above waterproofing only used when polyurethane foam insulation is used over the screed for non-traffic able roofs.

Cold applied waterproofing membrane for non-Traffic able roofs:-a) 2 coats of 2 component Elastomeric self adhesive membrane over primed, screeded surfaces with aluminum paint on top for U/V protection. Component Elastomeric self adhesive membrane shall consist of a mix of 9 volumes 'premix' - polymerizable black liquid and one volume of 'Activator' - straw colored liquid - laid to an average thickness of 1.5 mm. Top coat shall be sprayed with a layer of clean sand when it is still green, as a key for the U/V protection, which shall be done by two coats of aluminum reflective paint.

b) Rubberized bitumen/polyurethane membrane shall consist of standard rolls of self adhesive and self-sealing 1.5 mm. thick rubber-bitumen compound with solar shield a luminous to exposed top surface - all to be laid on primed screeded surface with necessary end laps and side laps as recommended by the manufacturers.

Traffic able Roofsa) 2 components Elastomeric membrane shall have average thickness of 1.5 mm. and shall be mix consisting of 9 volumes 'Premix' - polymerizable black liquid and one volume of 'Activator' - a straw colored liquid laid over primed roof surface.Rubberized bitumen/polythene shall consist of standard rolls of self-adhesive and self sealing bitumen/polythene waterproofing membrane to factory controlled thickness of 1.5 mm. confirming to B.S. Code of Practice 102.


b) Self adhesive membrane 4kg/m2 with angle fillet will be used as water proofing layer (polypit or approved equivalent).

Priming of Concrete Roof Slab Surfaces:Top surfaces of roof slab shall be primed and given two coats of Oxidized bitumen 115/15 at the rate 2 kg./m2 brush applied to cover all the surfaces - up stands, sleeves of ducts, pipes etc., that are required to covered with roof finishes mentioned above.

Sheathing Membrane:Polythene 'Visqueen' 500 Grade or similar membrane laid with necessary side laps (10 Cm.) and end laps as required (Min. 15 Cm.)

Concrete Passing Slabs:Pre-cast paving slabs shall be hydraulically pressed, square edges sizes 60 x 60 5 Cm. thick made from Portland cement and aggregates-all to comply Palestinian Standard.

Mastic Sealant:Mastic used for the joints shall be cold poured - 2 part polysulphide based sealants confirming to Palestinian Standard.

d) Type of Roof finishes based on the above Specifications:-1 Roof finishes Type A: (Non-Trafficable Roofs)

Step (1) : Priming of roof slab/surfaces Step (2) : Sand/cement screed Step (3) : Polyurethane foam Step (4) : U/V protective coating/waterproofing

2 Roof Finishes Type B: (Non-Trafficable Roofs)Step (1) : Priming of roof slab/surfaces Step (2) :Polystyrene rigid insulation slabs (boards) laid over primed surfaces of roof slab Step (3) : Sheathing membrane Step (4) : Sand/cement screed

Step (5) : Waterproofing

3 Roof Finishes Type C: (Non-Trafficable Roofs)Step (1) : Priming of the roof slab surfaces Step (2) : Rigid mineral wool insulation slabs Step (3) : Sheathing membrane Step (4) : Sand/Cement screed

4 Roof Finishes Type D: (Trafficable Roofs)Step (1) : Priming of the roof slab surfaces Step (2) : Thermal insulation Step (3) : Sheathing membrane Step (4) : Sand/Cement screed Step (5) : Roof waterproofing Step (6) : Sand/cement mortar (1:6) bed min. 2.5 Cm. thickStep (7) : 5 Cm. thick 60 x 60 Cm.

5. Contractor must use the type of finishes as specified on the drawings for the particular project or any other type of roof finishes specified above and approved by the . Work of the roof finishes shall be carried to the complete satisfaction of the . The roof shall be tested for water tightness by flooding the same with 5 Cm. deep sheet of water for 72 hours prior to initial take-over of the building.

6. Contractor must use the appropriate type of detail for horizontal and vertical joints as shown on the drawings. Up stands for expansion joints on the roof shall be properly covered with the waterproofing membrane over the plastered vertical and horizontal surfaces. Points shall be


properly sealed with approved mastic sealants and protected from damage by providing pressed aluminum sheet cover as indicated in details on he drawings.

14.3Metal Work 14.3.1 Generally

All materials shall be free from scale, rust damage or defects.All welding, brazing or hot forging shall be carried out by approved processes.All metalwork shall be approved by the Engineer or his representative before starting painting works.

14.3.2 Windows And DoorsThe following specifications relating to metal windows shall cover also metal casement doors and, where applicable, partitions. generally metal windows shall be supplied complete with frames, fixing lugs and glazing clips or beads. Composite windows shall be - supplied complete with the necessary transoms and mullions. Generally the windows will be required to open inward.

Mild steel windows shall be manufactured in accordance with B.S. 990 with regard to materials and workmanship. The windows shall be formed of hot rolled mild steel sections, electrically welded, and rustproof by either hot or cold galvanizing, metallizing or sheradizing process as required. The rust-proofing shall be sufficient to withstand the 72 hour salt-spray test as provided for in B.S. 1391. Opening sashes shall be fitted with steel hinges having brass pins. Pivoting sashes shall be fitted with bronze centers. Side hung or vertically pivoting sashes shall be fitted with sliding stays and handle fasteners with two point noses as shown on the Drawings or as specified in the Particular Specification. Top hung or horizontally pivoting sashes shall be fitted with brass peg stays. Button hung sashes shall be fitted with brass lever catches and, according to size, one or two steel side arms each. Aluminum windows shall be manufactured of extruded sections of Aluminum alloy, flash welded. Fittings shall be of aluminum alloy in accordance with Palestinian Standard. Fly screens shall fitted to all opening leaves of windows, consisting of aspirated metal sub-frame filled in with fly wire as previously described. The fly screens shall be adequately secured with suitable slips, set screws or turn buckles and shall be removable for maintenance purposes. Fly screen doors shall consist of similar sections to the metal casement doors and shall be fitted with removable panels of fly wire in a manner similar to that described for window fly screens.

14.3.3 SundriesWrought steel balustrades shall be provided to staircases and balconies as shown on the Drawings. Burglar bars and safety bars shall be provided to windows where shown on the Drawings. Cramps for fixing wood door and window frames shall be 20 cm long x 3 cm x 3 mm section and shall have one end bent and twice drilled for screwing to frame and other end fishtailed for building into walling. Cramps shall be galvanized or dipped in bitumen before fixing Mild steel ladders where required shall be as shown on the Drawings. Metal roller shutters shall be provided to sized shown on the Drawings. Each roller shutter shall be constructed of heavy-gauge metal slats and shall be complete, including channel iron guides, roller box, spindle and counter balance springs and with staple welded to door, hasp set in concrete floor and padlock.

14.4Plaster And Other Floor Wall And Ceiling Finishes Work14.4.1 MaterialsThe cement and water used for plastering shall comply with the requirements given under CONCRETE WORKS. The sand for plastering shall be clean, fine sand and shall be chemically and structurally stable. The sand shall be sieved and graded in accordance with the Table of Grading given below:-

TABLE OF GRADINGS-PERCENTAGE PASSING SIZES FOR PLASTERINGB.S. Sieve No. Inches Approximate

MillimetersUndercoat

Finish Coat

7142552

0.0950.0470.0240.012

2.4 1.2 0.60.3

95-10080-95 30-555-50

10095-10030-855-50


100 0.006 0.15 0-10 0-10

Note: The above figures represent the limits of percentages (by weight) passing sieves of the sizes mentioned. The gypsum plaster shall be of the hemi-hydrate type with a controlled setting time as Type 6 Clause B of Palestinian Standard. The resultant plaster shall be chemically inert when set, be capable of being trowelled to a smooth surface and shall be highly resistant to cracking and crazing. Imported lime shall be of the hydrate type complying with Class B of British Standard No. 890.

14.4.2 MixingThe methods of measuring and mixing shall be as laid down under CONCRETE WORKS and the proportions shall be in accordance with Mixing Table given below:-

Mixing TableNominal Mix Ratio Cement Kilos Sand

m3Imported Lime(Dry Hydrate) Kilos

1:4 cement 361 1.00 -

1:1 cement 442 1.00 -1:5 cement with 20% imported lime 1:5:1 289 1.00 124

1:4 Imported lime with 10% cement

1:10:2 1/2 145 1:00 161

With regard to the lime mortars gauged with cement, the addition, just before use, of the cement to small quantities of the lime/sand mix shall preferably take place in a mechanical mixing shall continue for such time as will ensure uniform distribution of materials and uniform color and consistency. It is important to note that the quantity of water used shall be carefully controlled. Gypsum plaster shall be mixed in a clean pail or other approved vessel. The required amount of water shall be placed in the pail and the plaster added gradually and allowed to soak for 5 minutes. It shall then be stirred to a uniform consistency free from lumps and no more material shall be mixed than can be used in half an hour.

14.4.3 WorkmanshipAll plastering shall be executed in a neat workman like manner. All faces except circular work shall be true and flat and angles shall be straight and level or plumb. Plastering shall be neatly made good up to metal or wood frames and skirting and around pipes or fittings. Angles shall be rounded to 5 mm. radius. Surfaces of undercoats shall be well scratched to provide a key for finishing coats. Screed marks or making good on under-coats shall not show through the finishing coats. Surfaces described as trawled smooth shall be finished with a steel or celluloid trowel to a smooth flat surface free from trowel marks. Surfaces described as floated shall be finished with a wood or felt float to a flat surface free from trowel marks. All tools, implements, vessels and surfaces shall at all times be kept scrupulously clean and strict precautions shall be taken to prevent the plaster or other materials from being contaminated by pieces of partially set material which would tend to retard or accelerated the setting time.

14.4.4 PreparationAll surfaces to be plastered shall be clean and free from dust, loose mortar and all traces of salts. Where cement plaster is to be applied to surfaces shall first be dashed with a mixture of Portland cement and (1:1) mix to form a key. All surfaces shall be thoroughly sprayed with water and all free water allowed to disappear before plaster is applied. Before plastering is commenced all junctions between differing materials shall be reinforced. This shall apply where walls join columns, where brick walls join block walls and similar situations where cracks are likely to develop and as directed by the . The reinforcement shall consist of a strip of galvanized wire mesh (10 to 15 mm. hexagonal mesh) 15 Cms. wide which shall be plugged, nailed or stapled as required at intervals of not exceeding 50 cms. at both edges.


14.4.5 CuringPlaster shall be cured after the application of each full coat by similar to those described in CONCRETE WORKS.

14.4.6 ApplicationAfter preparation of the surfaces as described in above the undercoat shall be applied to the required thickness between screeds laid, ruled and plumbed as necessary. When nearly set the surface of the undercoat shall be scratched as described. The undercoat shall be allowed to set hard and shall be curd as described. Where plastering is applied in one coat or where roughcast is to be applied the scratching should be omitted. The finishing coat shall be applied to the required thickness by means of a laying-on trowel and finished to give the required surface. The sprayed finish shall be applied with an approved machine to give a finish of even texture and thickness. The sprayed finish shall be applied in four separate coat allowing time for drying between coats. Application in one continuous operation to build up a thick layer will not be permitted. the total finished thickness of the four sprayed coats shall be not less than 3 mm. The sprayed finish shall not be applied until all repairs and making good to the undercoat are completed. Rain-water pipes, fittings and the like shall first be fitted, then removed during the spraying process and refitted and jointed afterwards. Any plaster which adheres to other pipes, doors, windows and the like shall be carefully removed before it has set. Curing shall take place after the application of the fourth coat.

14.5Painting And Decorating14.5.1 GenerallyEvery possible precaution shall be taken to keep down dust before and during painting processes. No paint shall be applied to surfaces structurally or superficially damp and all surfaces must be ascertained to be free from condensation, of florescence, etc., before the application of each coat. Primed or undercoated wood work and metal work should not be left in an exposed or unsuitable situation for an undue period before completing the painting process. No exterior or exposed painting shall be carried out under adverse weather conditions, such as rain, extreme humidity, dust storms, etc. Metal fittings such as ironmongery etc., not required to be painted shall first be fitted and then removed before the preparatory processes are commenced. When all painting is completed the fittings shall be cleaned and re fixed in position. The Contractor will be required to repaint at his own expense any work on which the paint is found to be incorrectly applied. The Contractor shall be responsible for protecting from damage the paint work and all other work during and after painting operations including the provision of all necessary dust heats, covers, etc. Brushes, pails, kettles etc. used in carrying out the work shall be clean and free from foreign matter. They shall be thoroughly cleaned before being used for different types or classes of material.

14.5.2 MaterialsThe decorating materials shall be obtained from approved manufacturers and shall be supplied in the manufacturers' sealed and branded containers. All materials must be thoroughly stirred before use. Details of mixing and application shall be in accordance with the specifications of the manufacturers concerned and to the approval of the . The mixing of paints etc., of different brands before or during application will not be permitted. No dilution of painting materials shall be allowed except strictly as detailed by the manufacturers and as approved by the . Mordant solution shall be equal in quality to "Litho form" manufactured by I.C.I. Ltd. Rust inhibitors shall be equal in quality to "James" brand Calcium Plum bate Primer manufactured by Foster, Blackett and James Ltd. or as described elsewhere herein. Fillers shall be "Polyfilla", "Alabastine" or other equal and approved. Thinners shall be approved turpentine or white spirit. Priming paints shall be:

(a) For wood work: Leadless gray priming paint in accordance with Palestinian Standard. Alternatively wood work of hard, non-absorbent timber, resinous timber of prominent grain shall be primed with one coat of aluminum sealer equal to "A 519-3648" manufactured by I.C.I. Ltd.(b) For steel work: Red oxide priming paint in accordance with Palestinian Standard (c) For galvanized, zinc or aluminum alloy surface: gray zinc chromate priming paint equal to "A 500-388" manufactured by I.C.I. Ltd.(dFor plaster, concrete and brickwork, ceiling boards etc.: Algalia resisting priming paint equal in quality to "A 500-368" manufactured by I.C.I. Ltd. Knotting shall be in accordance with Palestinian Standard. Stopping shall be hard stopping composed of paste white lead, gold size whiting. Undercoating shall be:(a) Zinc oxide based undercoating paint.


(b) White lead based undercoating paint in accordance with British Standard No. 2525. Colors shall approximate to the finishing paint.(c) Synthetic alkyd based undercoating equal to "Dulux" undercoating paint manufactured by I.C.I. Ltd. Finishing paints shall be:(a) Zinc oxide based oil paint in accordance with British Standard Nos. 277 (b White lead based oil gloss finishing paint in accordance with Palestinian Standard

.(c) Synthetic alkyd based finishing paint equal to "Dulux" finishing paint manufactured by I.C.I. Ltd.

Petrifying liquid shall be used undiluted as supplied by the manufacturer. A small quantity of water paint of the finishing color may be mixed with the petrifying liquid. Water paint shall be an approved brand of washable oil-bound water paint complying with British Standard No. 1053 Type A. Thinning shall be done with petrifying liquid or fresh water only. Emulsion paint shall be of the Polyvinyl Acetate (P.V.A.) type obtained from an approved manufacturer. The precise specification shall comply with the manufacturer's normal practice. In all cases thinning shall be done with thinners supplied by the manufacturer or fresh water only. Stain for wood work shall be an approved brand of oil stain complying with British Standard No. 1215. Varnish for wood work shall be an approved brand of exterior oil varnish complying with Palestinian Standard

14.5.3 Preparation Processa) Internal Plaster, Fair faced Concrete And Block work Surfaces shall be allowed to dry out completely and cracks shall be cut out and made good with suitable hard plaster or cement/sand mix as appropriate, such repaired portions shall be allowed to dry out. No painting shall be carried out on plastering less than five weeks old. Efflorescence shall be completely removed by rubbing down with dry coarse cloths followed by wiping down with damp cloths and allowed to dry. All surfaces shall be rubbed down with fine glass paper and brushed free of dust before applying any form of decoration. Surfaces which are to receive water paint shall be treated with one coat of petrifying liquid applied by brush and allowed to dry for at least twenty four hours before the application of water paint. A period of twenty four hours, or longer if necessary, shall be allowed between subsequent coats. Fair faced concrete and/or cement and sand plastered surfaces which are to receive oil paint shall be given one thin coat of oil putty and allowed to dry for at least two days. The surfaces shall then be rubbed down with fine glass paper and given a second thin coat of oil putty when completely set shall be rubbed down again with fine glass paper before applying the priming coat of oil paint. All surfaces which are to receive oil paint shall be treated with one coat of alkali resisting priming applied by brush and allowed to completely harden.

b) Steelworks including Windows, Louvers, etc. Internally and Externally If delivered galvanized, the surfaces shall be cleaned to remove grease and dirt before priming. Where rusting has occurred through damage to the galvanizing, such rust shall be removed by wire brushing back to clean metal and the galvanizing made good with a rust inhibiting agent. The surface shall then be treated with one coat of mordant solution and one coat of zinc chromate priming paint. If delivered primed, the surfaces shall be examined to ascertain that the priming paint is hard, firmly adhering and in good condition. If not satisfactory, the priming paint shall be removed and the surfaces cleaned to removed rust, and re primed. If the condition shall be cleaned to remove grease and dirt, minor damage to the priming paint being made with red oxide priming paint after removal of rust. If delivered un primed and not galvanized, the surfaces shall be cleaned to remove grease and dirt, and wire brushed and scraped to remove all rust and scale before applying a red oxide priming paint. Priming paint shall be brushed well into the surface and shall be allowed to dry and harden thoroughly before the application of subsequent coats. Items of steelworks such as frames to roller shutters, covers to expansion joints, etc., which are to be built into walls first be primed.

c) Exposed Service PipesCopper, aluminum and brass pipe work shall have the surfaces slightly abraded with glass paper and white spirit or similar solvent and wiped clean. No priming paint will be necessary, the surfaces being finished in two coats of glass paint. Steel pipes will be treated as for steelworks with the exception that galvanized pipes are to be treated with a zinc chromate priming paint. Coated soil pipes


shall be wiped clean and treated with two coats of knotting followed by priming paint as described above.

14.5.4 Finishing Progressa) Internal PlasterWhere emulsion paint is specified two coats shall be applied by brush in addition to any priming paint. Where water paint is specified two coats shall be applied by brush in addition to the petrifying liquid. The water paint shall be thinned to the consistency of thick mream. Where oil paint is specified this shall be two or three coat work as detailed in the Particular Specification, applied by roller or brush, but not by spray, to produce hard gloss, oil gloss, eggshell or flat finish as required. The finishing coat of paint to walls and ceilings shall be applied after the completion testing of the electrical installation. Any paint splashes on electrical fittings shall be carefully cleaned off.

c) Unplastered Concrete or Block workAs for plastered surfaces. Externally a cement type paint may be used, and shall be applied keeping a constantly wet edge, in strict accordance with the manufacturer's instructions.

d) Steelworks And Exposed Service PipesInternally, apply one coat gloss paint over two undercoats. Non-ferrous pipes shall be finished in two coats of gloss Externally, apply two coats gloss paint over one undercoat.


15.LANDSCAPING

15.1GeneralThe work covered by this division consist of providing all plant, labour and materials and performing all operations in connection with ground covers, plants, trees and soil.

15.2Product Delivery, Storage And Handling 15.2.1 Product DeliveryThe Contractor shall notify the Engineer of the delivery schedule 48 hours in advance so that plant material may be inspected on arrival at the site. Unacceptable plant material shall be removed from the site immediately.

The Contractor shall produce an itemized list, in duplicate of the actual quantity of plant material in each delivery so as to ensure satisfactory coordination of deliveries and to expedite the required inspection at the site. The itemized list of the plant material for each delivery shall include the pertinent data as specified in the list of required plants. The list and the necessary inspection certificates to accompany each delivery shall be given to the Engineer prior to acceptance and planting of the plant material.

Plant material delivered by truck shall be loaded so as to provide adequate protection against climatic, seasonal, and breakage damage during transit. Entire loads of plants shall be securely covered with tarpaulin or canvas to minimize wind whipping and drying. Rail cars or air freight containers shall be carefully loaded and adequately ventilated to prevent excessive transpiration of the plants during transit. Shipments made by rail or air to local freight yards or terminals shall be given special attention to ensure prompt delivery to the site and careful handling. Container grown trees shall be protected from sharp jolts during transit by tying the main stem to the container, using a strong twine from cutting on to the stem from becoming loose in the so8 mould, cracking the soil mould, or breaking the delicate surface surface roots. Care shall be taken to prevent the twine from cutting into the stem by using a padding of burlap or other suitable material. The ball of the large balled and buriapped plants shall be set in wood crates or property tied to a base to provide stability during transit. To prevent damages of the bark of trees with a stem diameter of more than 50 mm a special jute double layer should cover the stem, from the stem base up to the first branches. This should be done before any loading and transport operations. Additionally, the contractor has to ensure that the whole plant material is sprayed with insecticides and fungicides before transportation. This must be done twice with two weeks interval between the spraying operations.

Soil ingredients like fertilizer, peat moss, shredded bark, manure and organic resin foam shall be delivered to the site in the original unopened containers, bearing the manufacturer's name, trade name or trademark, the guaranteed chemical analysis and any other information needed to comply with local .statutes. In lieu of containers soil additives may be produced in bulk with a certificate indicating the above information accompanying each delivery.

15.2.2 Product StoragePlants not planted on the day of delivery at the site are to be stored and protected as follows:

Especially, if plants are imported, a heeling-in nursery should be provided, where plants have an opportunity to recover from their travel and get used to their new environment. Plants require a minimum of six weeks in this holding area. Time for this process must be incorporated into the construction schedule. This plant staging area should protect the plants from sun and wind and must have Irrigation. It should be located in a suitable area on site, which provides this protection. If no such area exists, the contractor shall be required to construct a lath house or other suitable construction which provides sun and wind protection for the plants.

All plants stored on site shall be protected from crying out at all times by covering the balls or roots with moist sawdust, wood chips, shredded bark, peat moss, or kept moist until planted by watering with a fine mist spray.

Seeds have to be stored dry and in -air-conditioned room with a maximum temperature of 25 degree Celsius .


Soil additives and other materials shall be kept in dry storage away from contaminants.

15.2.3 Product HandlingCare shall be taken to avoid damaging plants being moved from the nursery or storage area to the planting position. Plants shall be protected from drying out at all times. Balled and bunapped plants shall be handed carefully to avoid cracking or breaking the earth ball. Plants shall not be handled by the truck of stems.

Under no circumstances shall plants be dropped from box cars or trucks to the ground. Cracked or mushroomed plants balls will be rejected. Bare-root plants shall be "paddled" when removed from the heeling-in nursery to protect the roots from drying out. Plants shall be protected from drying out by a covering of burlap, tarpaulin or mulching material during transportation from the heeling-in bed to the planting position. Damaged plants will be rejected and shall be removed from the site immediately.

Big trees with a stem diameter of more than 100 mm the following will be necessary:Wooden battens (100 x 60 x 600 mm) shall be adequately padded with several layers of burlap and firmly wired in place around the trunk for protection from lifting devices during digging, transportation and planting operations. Under no circumstances will nailing of battens to trunk be allowed. Digging shall be by hand or by mechanical means or both.

15.3Plants And Seed Products15.3.1 Grass SeedGrass seeds shall be only cynodon dactylon for seeding in summertime and lollium perenne mixed with cynodon dactylon 50 % of each kind seeding in wintertime. Seed shall be stored in sealed , standard containers and should be described in terms of quality, quantity and Its origin. Each seed container shall bear the date of the last germination which shall be a date within a period of six months prior to commencement of planting operations. Seed that is wet, mouldy, or that has been otherwise damaged in transit or storage will not be accepted. The seed shall be free of field bindweed, hedgeweed and nutgrass seed. Seed should not contain noxious weed seed. Weed seed shall not exceed one percent. Common bermuda grass seed shall not contain in excess of three percent of giant strains of bermuda grass.

15.3.2 Ground Covers Ground covers shall be vigorous, have the number and length of runners and clump size specified, and the proper age for the grade of plants specified. Only ground cover plants well-established in removable containers, integral containers, or formed homogeneous soil sections shall be used. Plants shall have been grown or acclimatized under climatic conditions similar to those in the locality of the project. All ground cover plants shall be free from pest and disease, eggs and larvae and should have a vigorous root system. The ground covers to be used for slopes are Carbobrotus Edulis.

The minimum sizes of all plants for acceptance are measured before pruning and with brnaches in normal position. They shall have at least three well-developed branches or runners and grown 'for a period of at least 6 months. The minimum size of the root ball shall not be less that I liter in volume.

15.3.3 Shrubs Shrubs shall be symmetrically developed, well-branched, their structure and habit of growth shall be typical of the species of variety. Shrubs shall have grown in a container at least for six months for the root system to have developed sufficiently to hold its soil together in a fine and integral manner. No plants which are loose in their container shall be accepted. Shrubs shall be free from disease, pests, eggs or larvae.

Shrubs to be used in the work shall be Evergreen and Dedonia.Shrubs shall be measured when branches are in normal position from the ground level to the top of the shrub.

15.3.4 Trees Trees shall-be symmetrically developed, their structure and habit of growth shall be typical of the species or variety, and shall have straight boles or stems free from objectionable disfigurements. The


side branches shall start at least 500 mm from the ground line. Trees with abrasion of the bark, sunscalds, disfiguring knots, or fresh cuts of limbs over 30 mm which have not completely calloused, shall be rejected. If trees are container grown at least for 6 months, they shall have a sufficient root growth to hold the earth intact when the container is removed. If trees are imported, the contractor shall conform to the local regulations dealing with the importation of plant material. if not container grown, trees shall be balled with firm, natural balls of soil. Balled and burlapped plants shall be wrapped firmly with burlap, strong doth or plastic and tied. The wrapping material shall be capable of rotting in the ground and shall not be permanent nature.

Trees to be used in the work shall be

Latin Name Common Name Common UseEucalyptus Camaldulensis Red Gum Roads, Car Parks, Screen, Shade,

Ornamental Quercus Calliprinos Palestinian Live Oak Wind Break, Roads, Shade,

Ornamental Cupressus Sempervirens Varstricta Italian Cypress Wind Break, Roads

Ficus Nitida Wind Break, Screen, Roads, Ornamental

Ceratonia Siliqua St. Johns Bread (Carob) Fooder, Ornamental and Midecal Plant

DECIDUOUS TREES

Jacaranda Acutifolia Jacaranda OrnamentalDulenoux regia Dulenoux Ornamental

PALMS

Phoenix Date Palm Ornamental, timber, Fruit tree

FRUIT TREES

Citrus limon Lemon Ornamental, timber, Fruit tree

Ficus carica Edible fig Shade

Olea Europea Olive Ornamental, timber, Fruit tree

EVERGREEN SHRUBS

Carpobrotus Edulis Ice Plant Ground Cover, Rockery

Dodonaea Viscosa Hopseed Bush Hedge, Screen

Calliper measurement shall be taken at a point on the trunk 250 mm above natural ground level for trees up to 100 mm in diameter, and at a point 300 mm above the natural ground level for trees 100 mm in diameter. Spread dimensions shall refer to the main body of the tree and not from branch tip to tip.

15.3.5 Palm Trees Palm trees not container grown shall be planted immediately after delivery. They must be mother-plants with a root system which is not dried out. Additionally the stem and 50 % of the leaves should be protected against drying out with a double layer of jute bandage. Palm trees with a height of over 3 meters must have a ball with a diameter of mare than 1 meter.

Type to be used in the work is Cupressus Sempervirens Varstricta known as Italian Cypress


Palm trees shall be measured from the nursery grown ground line to the beginning of the spread branches.

15.4Soil 15.4.1 Top Soil Soil shall be free of admixture, subsoil and foreign matter and shad be taken only from well-drained areas, free of objects larger than 20 mm, and shall have the following characteristics :Clay max. 60 %Sand min. 40 % pH value max. 8.3

The Contractor shall provide soil analysis, which has to include the pH value. The electrical conductivity, CaC03, texture as well as the contents of nrtrogen, phosphorus, potassium and magnesium. The maximum levels of acceptance are:Available phosphorus P2 05 :10 mg/100 g soil Available magnesium Mg : 10 mg/100 g soil Available potassium K2 0 : 40 mg/100 g soil

The value of electrical conductivity shall not be higher than 2000 micro mhos. / cm- if it is higher, leaching of the soil in a well-drained area will be necessary with a suggested water quantity of 300 ltr/m2 with a soil depth of 300 mm.To get top soil, this wadi soil shall be mixed with sweet sand and soil improvers according to sand and soil analysis, and as stated in the project documents.The following mix states an example.Wadi soil 50%Sweet sand 20 % Soil improvers:Organic fertilizer 5% Peat moss 10% Shredded bark 10%Organic resin foam 5% Inorganic fertilizer 200 gr/m3

15.4.2 Sand Sand shall be natural, free of toxic material, friable and typical of the locality. Sand shall be reasonable free from subsoil, stones, earth dods, sticks, stumps, clay lumps, roots or other objectionable matter or debris and have the following characteristics:Clay (less than 0.002 mm) max. 3% Silt (0.002 - 0.005 m) max. 7 % Sand (0.05 - 2 mm) min. 90 % pH value max. 8Electrically Conductivity less than 1000 micro mhos/cm Exchangeable sodium (ESP) less than 10 % in ammonium acetate .

15.4.3 Top Soil Additives Inorganic granular compound fertilizer, uniform in composition, dry and free-flowing shall be used. They shall be delivered in original unopened containers and bear the manufacturer's analysis. They shall contain N (Nitrogen), P2 05 (Phosphorus) and K2 0 (Potassium) in an adequate mix to suit the purpose. The regulations governing inorganic fertilizer edited by the Ministry of Agriculture shall be adhered to. Organic fertilizer, Manure shall be a commercial product thoroughly pulverized, sterilized, decomposed, equivalent in every respect to packed sheep manure. Green manure shall not to be used.

Peat moss shall be of a quality acceptable for use as a soil amendment and shall have a pH range from 3.7 to 5.0. It shall be unfertilized and consist of sphagnum only.

Shredded bark made from conifers shall be proprietary decomposed bark in sealed containers and shall have the following specification:Maximum water capacity 50 %


Nirogen stabilised pH value 5, 5-7

available nutrients:Nitrogen N 100 - 250 mg/ltrPhosphorus P2 05 200- 400 mg/ltrPotassium K2 0 200-600 mg/ltrMagnesium Mg. 300 mg/ltr

Other soil additives such as phosphates and silicates can be used with the approval of the Engineer. The materials mentioned above are listed as examples only and are not limiting.

15.5Irrigation Water Fresh water from the underground water tank shall be used to irrigate areas of splinkler system as shown in the drawings, while the treated effluent water will be used in the drip system.

15.6Accessories 15.6.1 StakingStakes for supporting trees shall be of healthy wood, uniform in size, reasonably free from knots and capable of standing in the ground for at least two years. For small trees with a clear stem of up to 1 meter, a stake of minimum 50 mm in diameter and 2 meter in length (750 mm in the ground) shall be used. For larger trees with clear stem of up to 1.8 meter, a stake of minimum 75 mm in diameter and 3 meter in length (1.0 meter in the ground) shall be used.For trees with clear stem of more than 1.8 meter or 3 meter in height, the method of wiring shall be used.

15.6.2 Tree Wrapping MaterialTree wrap shall be two thickness of kraft paper glued together with a layer of bituminous material. Wrapping material shad be a minimum of 100 mm in width and have a stretch factor of 33 1/3 percent Twine for typing shall be a lightly tarred medium of coarse sisal yarn.

15.6.3 WiringWire for tree bracing and guying shall be pliable 2 mm to 3 mm diameter galvanized soft steel wire.Cable shall, be 4.5 mm diameter, seven-strand cadmium-plated cable- Cable clamps and tumbuckles shall be galvanized steel of size and guage to provide tensile strength equal to that of the cable. Tumbuckle opening shall be at least 75 mm.Chafing guard shall be a two-ply reinforced rubber or plastic garden hose of unrform colour throughout the work.

15.6.4 DrainageWhen shallow soil is underlaid by a layer of impervious soil or hadrpan and excess water cannot drain away, the sub surface plowing is required.

15.6.5 Pit FillingPorous fill for plant pit and bed drainage: Granular fill for filling over excavations and for bedding of pipes shall consist of uniformly graded sand stone, gravel, or stone screenings free from soft or harmful particles or other objectionable material.

15.7Execution

15.7.1 InspectionPlants shall be subject to inspection and approval at the place of growth and upon delivery for on formity to project documents as to quality, size and variety.

The source and quality of soil and sand shall be subject to inspection and rejection upon delivery at the site or during the progress of work. The contractor shall ensure that an independent soil analyst prepares a physical and chemical analysis of the soil in accordance with the top soil specification together with a


report and recommendations on fertilizer treatment. The soil analysis report, fertilizer recommendations and soil source shall be made available to the Engineer prior to approval.

No soil shall be brought on site prior to approval by the Engineer. The approved fertilizers and other Soil improvers shall be added to the top soil in accordance with the soil analyst's recommendations.

Water has to be tested periodically and also throughout the maintenance period. The contractor shall provideequipment for testing the electrical conductivity of water.

15.7.2 PreparationThe soil shall be conditioned by adding soil amendments and nutrients in compliance with this specifications and the recommendations of the soil analysis report. Fertilizer shall be applied not more than 24 hours in advance of tilling operations. Fertilizer shall be applied notmore than 24 hours In advance of filling operations. Fertilizer shall be applied not more than 24 hours in advance of tilling operations. Fertilizer shall be spread witha fertilizer distributor. All amendments and nutrients shall be thoroughly mixed and incorporated into the soil by using a roto-tiller.The seed bed shall be raked, dragged and then rolled making passes in two directions. Tillage depth shall be, 300 mm. Before during and after all mixing operations, water shall be added to soil and soil additives.

Stockpiled, wind blown sand shall be cleaned of all stones, sticks, plants and other foreign materials before being spread. Sand shall be placed and spread over all areas not required to be developed otherwise. Sweet sand shall be placed, and spread in all areas designated for planting and garden areas to a depth of 150 mm, including filling plant pits to the required depths. Both types of sand shall be supplied and installed to a depth sufficiency greater than required so that after natural settlement the completed work will conform to the lines, grades and levels indicated.

Vegetation surfaces shall be fine-graded after applying soil improvements materials. Surfaces are to be compacted in such a way as to prevent subsequent setting, and without damage to any roots to a standard proctor density of 80 to 85 %.

After sand has been spread, it shall be carefully prepared by harrowing and hand raking. All large stiff clods lumps, brush, roots, stumps, titter and other for lawn areas shall be left smooth for ease of mowing.

15.8Planting And SeedingThe season for planting materials other than bare root plants shall be between November and March. Bare root plants should be installed during the months of January and February.

15.8.1 Lawn Lawn areas must have a layer of top soil mix with a minimum depth of 300 mm. Before seeding the ground level shall be prepared by leveling + 20 mm on 10 m distance and stones and branches shall be removed .Especially edges and connections to constructions have to be compacted.

Time for seeding cynodon dactylon is between March and October and the average air temperature shall be higher than 25 degree celsius. Time for seeding the mixture of lollium perenne and cynodon dactylon is between October and March and the average air temperature shall be higher than 10 degree celsius.When delays in 'operations extend the work beyond the most favorable planting season for species designated or when conditions are such by reason of drought, high winds, excessive moisture, or other factors that satisfactory results are not likely to be obtained, work shall be halted as directed and resumed only when conditions are favorable or when approved alternative or corrective measures and procedures have been effected. If, on inspection, certain areas are not adequately seeded, these areas shall be seeded again and maintained.


For large areas, where seeding with machine equipment necessary, the quantity of seed shall be 4Q g/m2- For small parts where hand seeding is allowed, the quantity of seed to be used shall be 60 g/m2.

Seed shall be spread with hydraulic seeding equipment or with the sowing equipment. Small areas may be seeded by hand. Seed shall be distributed uniformly over designated areas.Half of the seed shall be sown with the shower moving in one direction, and the remainder with the shower moving in right angles to the first sowing. Seed shall be covered to an average depth of 20 mm by brush, harrow, cultipacker, hand rake with wood tines or other adequate device. Seed shall not be spread during windy weather.

Drill seeding shall be accomplished using equipment with drills set not more than 20 mm apart. Seed shall be sown uniformly in. areas to an average depth of 20 mm. immediately after the seeding operations have been completed the surface shall be compacted by a cult packer, roller or other equipment.When planting by machine the roller shall be operated immediately behind the planter.

Special maintenance shall be done between seeding date and preliminary handing-over date. The operations which will be necessary are different and depend in season and actual situation. For handing over and first acceptance it must be possible to walk an the grass without damage. The growth must be uniform throughout the lawn area. The last mowing operation shall be less than 5 days before handing over inspection. More than 90% of the area must be covered with grass.

Including rainfall the lawn shall be irrigated as follows: From seeding date up to germination 4-5 times each operation 8 ltr/m2 each week After germination 2-3 times total 30 ltr/m2 each week

proper fertilization shall be provided against traffic, animals and other use by erecting and placing barricades and warning signs immediately after the planting is complete.

15.8.2 Ground Covers Planting season for ground covers shall be between November and March.Ground covers beds shall be dug to depth of 400 below final grade and filled up with top soil. Rocks and other underground obstructions shall be removed to a depth necessary to permit proper planting.After watering the soil, the ground covers shall be located on the bed in final position. After excavation, ballad and burlapped plants, shall be set in sweet sand which, shall be compacted around bases of balls to fill all voids. All burlap, ropes and containers shall be removed from the root balls. Roots of bare root plants shall be property spread out and sweet sand carefully worked, or frayed roots shall be cut off clean.

15.8.3 Shrubs And Trees Planting season for Shrubs and trees shall be between November and March.The location of all plants shall be staked out before excavating plants pits. If pits are prepared and backfilled prior to planting, their location shall be marked and recorded on drawings so that when planting proceeds they can easily be located.

Plants Pits Plant pits shall be excavated with sides as nearly vertical as possible with following sizes:

Shrubs : Shrub pits shad be 300 mm greater in diameter than the spread of the roots and sufficiently deep to allow a minimum of 100 mm top soil mix under the root balls. If the height of shrubs is not more than 80 cm, the size of the shrub pits should be 500 x 500 mm .

Trees : Tree pits shall be 600 mm greater in diameter than the bail of earth or spread of roots of the tree and sufficiently deep below root system to allow for a 150 mm thick layer of planting soil beneath the ball or roots. If the tree is not higher than 2 meters, the tree pit shall have a minimum size of 1000 x 1000 x 1000 mm.

In salty ground, all shrubs and tree pits shall be irrigated with sweet water for two consecutive days to ensure adequate leaching of the salt. The water applied per day shall be twice the volume of the pit. The bottom of the pit shall be filled with sweet sand about 500 mm deep. If there is a rocky ground underneath stone mulch shall be filled in about 200 mm deep. Between the stone mulch and the top soil, a filter sheet of fiberglass shall be installed. The rest of the plant pit has to be filled with top soil .


Before planting container grown plants some of the roots shall be cut and removed, so that they are matted at the bottom circling around the outside of the root ball. In freeing the roots at the periphery of the soil, some of the soil shall be broken away to provide better contact between the root ball and the fill soil. With balled and burped plants the burlap shall be folded back at least 5 cm below the soil level. The burlap shall be sliced carefully on the sides and at the bottom of the root ball to allow for easy root penetration. The hole shall be backfilled with top soil. Then a shallow basin shall be built around the tree pit, so that water soaks down into the root ball.Staking should be done to support and protect the plant. It shall be done at the same time as planting. For vines only one stake snail be used, whereas for trees two stakes are necessary. The trunk shall be tied to the stakes in one level.Stakes shall be at a right-angle to the most troublesome wind. Trees with a height of more than 3 meters or with a dear stem of more than 1.8 meter have to be anchored using 3 stakes and guy wires.

15.8.4 Palm Trees Planting season for palm trees shall be between September and October or March and April.The size of pits for palm trees shall be as follows:

Palm tree up to 4 meter - 1.5 m deep 2.5 x 1.5 m wide Palm tree up to 4 meter - 2.0 m deep 2.0 x 2.0 m wide

if there is a rocky ground, adequate drainage shall be installed.Before starting planting, all injured, dry and damaged roots shall be cut off, the leaves of the palm trees generally have to be cut back by a quantity of 30 % in one level; This is to reduce water requirement After setting the palm tree, the ball and root system shall be surrounded by sweet sand. The rest of the pit shall be filled with top soil.The trunk and 50 % of the spread branches have to be protected against drying out by covering with a double jute layer.

Palm trees with a trunk height of more than 1 meter should be anchored with guy wire and 3 stakes to support against the wind.

15.9Landscape Maintenance15.9.1 MaintenanceMaintenance shall commence immediately after each plant is planted and shall continue in accordance with the following requirements:All planting shall be inspected at least once monthly during the maintenance period.All site planting shall be maintained in a healthy growing condition until completion of the maintenance period.Maintenance shall include watering, weeding, cultivating, malching, fertilizing, tightening and repairing of guys, removal of dead materials, resetting plants to proper grades or upright positions, spraying against inectial disease and all other necessary operations normally required to sustain, healthy growth. All wrapping and guying material shall be removed at the end of the maintenance period.

15.9.2 ReplacementReplacement shall be made by the contractor of any trees or plants that are dead or that are in unhealthy or unsightly condition or that have lost natural shape due to dead branches, excessive pruning or inadequate or improper maintenance.All replacement planting is to be done no later than the earliest planting season following receipt or request for replacement from Engineer. Ail areas damaged by tree or shrub planting or replacement operations are to be fully restored to their original condition.


16.BITUMINOUS CONSTRUCTION

16.1MATERIAL16.1.1 ScopeAll material sources and the quality of materials proposed for use in the works shall be approved prior to procurement or processing material from such sources. Inspection, sampling , testing and re-testing as necessary, shall be at the contractors expenses.

16.1.2 Sampling And Testing Of Aggregate - In order to ascertain the properties of aggregate materials, the contractor shall submit for testing and approval, representative samples of all materials intended for corporation in the works, prior to starting quarry operations, the samples shall be taken by contractor in the presence of the Director of works or his representative.

- Tests performed by the contractor shall utilized in assessing the locations, extent of deposits and quantities of materials which will conform to the specifications when properly processed. All testing as carried out by the contractor shall in no way obviate the need for further testing by Director of works or his representative.Approval of specific sources of materials shall not be construed as final approval and acceptance of materials from such sources.

- Unsatisfactory materials whether in place or not, shall be removed promptly from the site. The contractor shall furnish all necessary material, labor , tools, and equipment and transport required by the Director of works or his representative for such inspections.

16.1.3 Aggregates For Bituminous Paving Mixes1. Aggregate for use in bituminous, binder and wearing courses, shall consist of crushed stone.2. course aggregate shall be the fraction of crushed aggregate material retained on 4.75 mm (No. 4)

sieve. Fine aggregate shall be the fraction of crushed aggregate material passing 4.75 mm (N0. 4) sieve. Mineral filler shall be added when the combined grading of course and fine aggregates is deficient in material passing 0.075 mm(No. 200) sieve.

3. The material from hot bins passing the number 40 sieve (0.425 mm) when tested in accordance with AASHTO T90 shall be non plastic.

4. Aggregate shall not contain gypsum more than 1% and the course fraction of the aggregate shall not contain more than:5% chert and flint for aggregate to be used in the Wearing course.5% chert and flint for aggregate to be used in the Binder course.

5. Aggregates shall be of uniform quality, free from decomposed stone, organic matter, shale.6. The percentage by weight of friable particles, clay lumps, and other deleterious matter shall not

exceed 1% as determined by AASHTO T112.7. Aggregate particles shall be clean, hard, durable and sound. Crushing shall result in a product such

that, for particles retained on 4.75 mm (No. 4) sieve, at least 90% by weight shall have 2 or more fractured faces.

8. The flakiness index and the elongation index test should be conducted in accordance with BS 812, the following are the maximum limits:

Wearing Course & Binder Course: Flakiness Index F.I = 2530Elongation Index E.I. = 2530

9. Aggregates shall be washed if directed, to remove any clay lumps, organic matter, adherent dust or clay films or other extraneous or deleterious matter that may prevent or detract from proper adhesion of bitumen to the aggregate particles.

10. Material filler shall consist of fine divided mineral matter such as limestone dust if added sperately; hydrated lime; other non-plastic mineral filler, free from clay and organic impurities; or Portland cement, conforming to AASHTO M17.


11. The mineral aggregate for the base course shall be of such size that the percentage composition by weight as determined by laboratory screens, will conform to the grading specified in the following tables. Grading of the aggregate shall be determined by ASTM C 117 and C 136.

Aggregate Grading (asphalt base layer of ¾" aggregate size)

PavementSieve Size

(square opening)Percentage by Weight Passing

Square Mesh Sieve

Base

1½"1" (25.4 mm)¾" (19.0 mm)½" (12.5 mm)3/8" (9.5 mm)

No. 4 (4.85 mm)No. 8 (2.36 mm)No. 20 (1.18 mm)

No. 50 (0,300 mm)No. 80 (0,150 mm)No. 200 (0,075 mm)

-100

70 - 10053 - 9040 - 8030 - 5623 - 3813 - 275 - 174 - 142 - 8

Aggregate Grading (asphalt wearing layer of ½" aggregate size)

SievePercentage by Weight

Passing Sieves1½"

1" (25.4 mm)¾" (19.0 mm)½" (12.5 mm)3/8" (9.5 mm)

No. 4 (4.25 mm)No. 8 (2.36 mm)No. 20 (1.18 mm)No. 50 (0,300 mm)No. 80 (0,150 mm)No. 200 (0,075 mm)

Bitumen content by weight of total mix (%)

-100

90 - 10071 - 9056 - 8035 - 6523 - 4914 - 435 - 194 - 152 - 84 - 6

Aggregate Grading (asphalt wearing layer of 3/8" aggregate size)

SievePercentage by Weight

Passing Sieves

½"(12.52 mm)3/8" (9.53 mm)

No. 4 (4.75 mm)No. 8 (2.36 mm)

No. 50 (0.300 mm)No. 200 (0.075 mm)

Bitumen content by weight of total mix (%)

10090-10060-8035-656-252-104-6

12. The loss in weight of aggregate after 500 revolutions, when tested in accordance with AASHTO T96, shall not exceed 35%.

Ratio of wear loss = is less than or equal 25.

13. When tested for soundness in accordance with AASHTO T104 the course aggregate (retained on No. 4 sieve) shall not shown sings of disintegration and the loss by weight after 5 cycles shall not exceed 9% in the case of the sodium sulphate test and 12% in the case of the magnesium sulphate test.

14. When tested for resistance to stripping in accordance with the AASHTO T-182 at least 95% coated particles should be achieved. Scandinavian test shall be carried out and at last 60% of the coarse


aggregate surfaces area shall remain coated with a bitumen film especially for exposed surfaces other wise anti stripping agent must be added to achieve the required coating.

15. The material shall contain minimum 50% sand equivalent. Test sample shall be taken from hot bins. 16.1.4 Heating Of Bitumen1- Heating equipment shall be of an approved type. Any method of heating that introduces free steam or

moisture into the bitumin will not be approved.2. Bitument shall not be heated more than 170c. materials heated in excess of this temperature will be

rejected and shall not be used in the works.3. Heating of bitumen shall be uniform and under control at all times, to the specified temperature. The

circulation system shall be of adequate size to insure proper and continuous circulation of bitumen during the entire operating period.

4. Thermometers of adequate range (calibrated in 2 degrees c increments) for accurately measuring the temperature of the bitument, shall be located so as to be readily visible and shall be kept clean and working order at all times.

16.2Bituminous Prime And Tack Coats16.2.1 Scope This work shall consist of furnishing and applying and MC cutback bitumen prime coat to a previously constructed aggregate base course and applying tack coat on Asphalt or concrete surfaces all as and where shown on the Drawings.

16.2.2 Medium Curing Cutback Bitumen1. MC-70 cutback bitumen for prime coat shall be used as recommended by ASTM D2399-83 for open

and tight surface, and RC-70 should be used as tack coat.2. All surfaces to receive either prime or tack coats shall conform with the specified tolerances and

compaction requirements and shall be properly cleaned and finally approved before applying any bitumen material.

3. Application of prime and tack coats shall be performed only when the surface to be treated is sufficiently moist and atmospheric temperature is above 15 c. There should be no fog, rain , strong winds, dusty conditions, or dust storms.

4. The surface of all structures shall be protected in an approved manner during the equipment operation. The contractor shall be responsible for making good any staining or damage of the structures to the satisfaction of the Director of works or his representative

5. Traffic shall not be permitted to surfaces after they have been cleaned and prepared for prime coat application.

6. The contractor shall maintain prime or tack coats until it is covered by the subsequent pavement course. Any area where the coats have been damaged shall be cleaned of all loose material and re-applied at the contractor's expense.

7. Applying temperature of MC- 70 shall be 45-80c.8. Areas to be primed shall be including 200 mm widths outside the edge of the permanent line.9. Application rate for prime coat shall be 1 lit/sq.m and tack coat application shall be 0.5 lit/sq.m.10. Asphalt pavement shall not be placed on prime coat before 24 hours, and no traffic is allowed to pass

on prime coat.

16.3Bituminous Courses16.3.1 ScopeThis work shall consist of the general requirements of furnishing materials, mixing at a central mixing plant, spreading and compacting bituminous courses.

16.3.2 Job Mix And Project Mixes1. The contractor shall submit his proposed Job Mix Formula for approval , at least 30 days prior to

beginning production. Therefore , samples from materials use in the preparing mix design ( aggregates and bitumen) shall be sent to specialized laboratories to be tested for final approval of mix design.

2. The Job Mix Formula be established by the contractor, under the supervision of the Director of works or his representative, in the field laboratory Mix design procedures shall conform with the Marshall method of mix design. All trial mixes shall be prepared and tested by the contractor in the presence of the Director of works or his representative .


3. The Job Mix Formula shall specify a combination of mineral aggregates including filler and bitumen in such proportions as to produce a Job Mix which is within the limits of the specified gradation and bitumen content ranges and which meets the Marshall test requirements. It shall also stipulate the mixing temperature at discharge from the mixer which, unless otherwise directed, shall be 170 C.

4. The Marshall test procedure shall be used to determine the percentage of bitumen to be incorporated in the mix. The Job Mix Formula shall take into consideration the absorption of bitumen into the aggregates. Air voids shall be calculated in accordance with the procedure given in the Asphalt Institute Manual, MS-2.

5. When compacting specimens on accordance with the Marshall test procedure, the number of blows applied with the compaction hammer shall be 75 on each test.

6. In order to meet the requirements, an approved additive such as Portland cement, hydrated lime or liquid antistrup agent, may be required in the Job Mix. Portland cement shall meet the requirements of ASTM M 85. Hydrated lime shall meet the requirements of ASTM C207, Type N. Cement or hydrated lime will normally be required in the approximate range of 2-3% by weight of the aggregates and shall be added at the cold feed in dry or slurry form as directed. Liquid antistriping agent, if needed will normally be required in the approximate range of 0.6-1.0% by weight of the bitumen, or according to the manufacturers specifications.

7. Upon receipt of approval of the Job Mix Formula, the Contractor shall adjust his mixing plant to proportion the individual aggregates, mineral filler and bitumen to produce a final project mix within the limits given in Table shown with respect to the Job Mix gradation:-

Maximum Variations of Project Mix from Approved Job MixSieve Designation (squre openings)

Specified Tolerances

9.5 mm (3/8 in.) and above 5.0%4.75 mm (No. 4) 4.0%2.36 mm (No. 8) 4.0%1.18 mm (No. 16) 4.0%0.600 mm (No. 30) 4.0%0.300 mm (No. 50) 4.0%0.150 mm (No. 100) 4.0%0.75 mm (No. 200) 1.5%Bitumen Content 0.3%Temperature of Mix on discharge temperature

5 C of the specified mixing

8 Conformance to gradation requirements will be determined on the extracted aggregate in accordance with AASHTO T 30. The bitumen content shall be determined in accordance with AASHTO T 164.

9 The participation of the Director of works or his representative in the preparation of the Job Mix Formula shall in no way relieve the Contractor of responsibility for producing project mixes meeting the specified requirements.

10 At the commencement of the contract one copy of the ASTM, AASHTO and Manuals MS-2 MS3, MS and MS22 shall be furnished by the contractor for use by Director of works or his representative.

16.3.3 Spreading And Finishing Equipment1. Bituminous course shall be spread and finished using approved type, self contained, power-propelled

pavers of sufficient capacity. Pavers shall be provided with electronically controlled vibratory screed or strike-off assembly and shall be capable of spreading and finishing the course of bituminous mix to the proper thickness and in lane widths applicable to the typical cross sections shown on the Drawings.

2. The pavers shall employ mechanical devices such as equalizing runners, straightedge runners, evener arms or other compensating devices, to maintain trueness of grade and confine the edges of the mix to true lines without the use of stationary side forms. Joint leveling devices shall be provided for smoothing adjusting longitudinal joints between lanes.

3. The paver shall be equipped with receiving hopper having sufficient capacity for a uniform spreading operation. The hopper be equipped with a distribution system to place the mix uniformly in front of the full length of the screed.

4. The screed or strike-off assembly and extensions shall effectively produce a findhed surface of the required evenness and texture without tearing, shoving, or grouging the mix.


5. The paver shall be capable of being operated at forward speeds consistent with satisfactory laying of the mix. Speed shall be fully adjustable

6. The Contractor shall make available, for refference by the Director of works or his representative, the manufacturer's instruction and operating manuals for each paver intended for use

16.3.4 Surface Preparation.1. When the bituminous mix is to be placed on a base, course the surface shall be prepared to meet the

appropriate specified compaction and surface tolerance requirements. The surface shall then be primed as specified “Bituminous Prime Coat”. No bituminous mix shall be laid on a prime coat until it has been inspected and approved.

2. Broken, soft, or unstable areas of aggregate base course shall be removed and replaced. The areas shall be excavated to a depth as directed and refilled with the specified bituminous mix.

16.3.5 Delivery, Spreading And Finishing a) Delivery of Mix to Site 1. A sufficient number of haul vehicles shall be provided so that adequate supplies of mix are delivered

to ensure that continuos paving will be achieved.2. Hauling equipment for aggregates and bituminous mixes shall consist of vehicles having dump bodies

suitable for dumping materials in a windrow or in spreader boxes. The bodied shall be so constructed that their volume measurement can be accurately determine. They shall be constructed and maintained such that loss of materials during hauling operations will not occur.

Dump controls shall be capable of operation from the driver’s seat.3. Hauling equipment for hot bituminous mixes shall have tight, clean, smooth metal beds which are

periodically thinly coated with a lime solution or other approved material to prevent adherence of the mix. All hauling units shall be equipped with a canvas or other approved type cover which shall be used to cover the hot material upon loading at the mixing plant and shall not be removed until the mix is discharged into the paver.

4. The dispatching of the hauling vehicles to the site shall be so scheduled that all material delivered is placed at least 90 minutes before sunset to allow sufficient time for compaction. Delivery of material shall be at a uniform rate and in an amount well within the capacity of the paving and compacting equipment.

5. The mix at delivery to the paver shall be not more than 10C below discharge temperature at the mixing plant. The minimum temperature for the commencement of breakdown rolling is 120 C. Mix loads of temperature less than 120C shall not be accepted, and the load shall be disposed of and another load used. If there consistent failure to meet the temperature requirement the Director of works or his representative shall order paving operations to stop until suitable measures are taken by the Contractor to ensure that temperature requirements are met.

6. Each haul vehicle shall be weight after each loading at the mixing plant and accurate records shall be kept of the gross weight and net weight of each load, for each vehicle dates and time of loading.

b) Setting Out Reference Line1. The Contractor shall survey the centerline profile and crown of the existing surface or base and

determine a reference grade line which will be submitted for approval. A reference line of wire or suitable cord shall be installed at a uniform grade parallel to the approved reference grade line such that conformance with the required geometric, surface tolerance and minimum thickness requirements shall be ensured.

2. The reference line shall be maintained taut and free from sags at all times during spreading and initial compacting operations.

3. A wire or cord reference line shall be installed on both sides of the paver for the initial bituminous course being laid. Thereafter only one reference line will normally be required, if the paver is equipped with adequate automatic superelevation control.

c) Spreading and Finishing 1. Bituminous mixes shall be laid only when the air temperature is at least 5 degrees C or above when

the existing surface is free from moisture, and when the weather is not foggy, rainy, dusty or excessively windy (particularly at low temperatures).

2. After completion of surface preparation, the bituminous mix shall be spread and finished true to crown and grade by approved automatically controlled bituminous pavers. The mix may be spread


and finished by approved hand methods only where the Director of works or his representative determines that machine methods are impracticable. Hand methods include heated hand tampers of at least 10 kg weight and approved type mechanical (vibratory) tampers.

3. The paver shall spread the bituminous mix without tearing the surface and shall strike a finish that is smooth, true to cross section, uniform in density and texture and free from hollows, transverse corrugations and other irregularities.

4. The paver shall be operated at a speed which gives the best results for the type of paver being used and which coordinates satisfactorily with the rate of delivery of the mix to the paver. A uniform rate of placement shall be achieved without repeated intermittent operation of the paver.

5. The mix shall be delivered to the paver in time to permit completion of spreading, finishing and compaction of the mix during daylight hours.

6. If during laying, the paver is repeatedly delayed because of lack of mix or if the paver stands at one location for an extended period, resulting in the (unrolled) mat under and adjacent to the rear of the spreader falling below the minimum temperature for breakdown rolling, the affected portion of mat shall be cut out and discarded and a transverse joint shall be constructed. Paving shall not recommence until the Director of works or his representative is satisfied that paving will proceed without interruptions.

7. Contact surfaces of curbing, gutters, manholes, and similar structures shall be painted with a thin, uniform coating of tack coat material. The bituminous mixture shall be placed uniformly high near the contact surfaces so that after compaction it will be 10 mm above the edge of such structure.

8. If during the paving operations, it is found that the spreading and finishing equipment in operation leaves in the pavement surface tracks or indented areas or other objectionable irregularities that are not satisfactorily corrected by the scheduled operations, the use of the equipment shall be discontinued, until faults are corrected to the approval of the Director of works or his representative. If this is not possible, other satisfactory spreading and finishing equipment shall be provided by the Contractor.

9. Transverse joints in succeeding layers shall be offset by at least 2 m. Longitudinal joints shall be offset at least 150 mm.

10. Bituminous mix shall be spread in one or more layers so that, after rolling, the nominal thickness of each layer of the compacted bituminous material does not exceed 2 to 3 times maximum size of aggregate. This maximum thickness may be increased slightly when such increase is more appropriate to total pavement thickness and provided the Director of works or his representative determines that such increased thickness will not be detrimental to the quality of the finished bituminous course, and the Contractor can show that the required density is attained throughout the layer thickness.

11. Transitions and structure approaches shall meet the design criteria for geometric, the surface tolerance specifications, and shall not be visually discontinuous or abrupt in appearance.

d) Joints and Edges1. All joints between old and new pavements or between successive days’ work shall be as to ensure

thorough and continuous bond between the old and new material.2. Before placing fresh mix against previously laid, the contact surface shall be cut back to a near

vertical face, and shall be sprayed or painted with a thin uniform coat of tack coat material. Longitudinal joints shall be made by overlapping the paver screed on the previously laid material (cut back as necessary ) and depositing a sufficient amount of fresh mix so that the joint formed will be smooth and tight.

3. Unsupported edges of bituminous layers shall be rolled immediately following the rolling of the longitudinal joint. The material along the unsupported edge may, if approved, be raised slightly by hand methods, to ensure that the full weight of the roller will bear fully on the edge material

4. On completion, the longitudinal edges of bituminous pavement shall be true to the width and alignment as shown on the Drawings. The edges shall be cut back if necessary prior to rolling, additional mix placed manually in a longitudinal strip adjoining each pavement edge, and the edge rolled down to a neat 3:1 (H:V) slope.

5. Transverse joints shall be carefully constructed and thoroughly compacted to provide a smooth riding surface. Joints shall be straight-edged and string-lined to assure smoothness and true alignment

e) Compaction1. After spreading and strike-off, and as soon as the mix conditions permit the rolling to be performed

without excessive shoving or tearing, the mixture shall be thoroughly and uniformly compacted, using approved types, sizes and number of rollers. rolling shall not be prolonged to the point where cracks appear or shoving or displacement occur.


2. All rollers shall be self-propelled vibratory steel wheel, 2-axle tandem steel-tired and pneumatic-tired types, in proper operating condition, capable of reversing without backlash or tearing of the surface, and shall be operated at numbers of rollers required is 3, of which one must be pneumatic type. The Contractor shall select a suitable method and pattern of rolling that will achieve the required compaction, to Director of works or his representative approval.

3. Prior to use on Site of pneumatic-tired rollers, the Contractor shall furnish, for reference and retention by the Director of works or his representative, manufacturers’ charts or tabulations showing the contact areas and contact pressures for the full range of tire inflation pressures and for the full range of tire loading for each type and size of compactor tire to be used. The Contractor shall ensure that tire pressures are maintained at all times in conformity with such charts or tabulations. The maximum allowable tolerances shall be plus or minus 35 KN/sq.m (5 psi).

4. Rollers should move at a slow but uniform speed, generally with the drive roll or wheels nearest the paver.

5. Minimum temperature of the mat at which rolling shall be allowed to start is 120c. 6. Breakdown rolling shall be consist of 3 complete coverage unless otherwise directed Rolling shall be

longitudinal, and over lapping on successive trips by at least one half the width of the rear wheels.7. To prevent adhesion of the mix to the rollers, the wheels shall be kept lightly moistened with water.

Excessive use of water will not be permitted.8. The initial or breakdown rolling shall be followed by intermediate rolling involving 3 coverages with

pneumatic-tired rollers unless otherwise specified.9. Finishing rolling shall then be carried out by means of tendem power steel rollers unless otherwise

designated. If specified density is not achieved, changes shall be made in size and number of rollers being used to ensure the compaction requirements are met.

10. The compacted density shall be equal to or more than 97% and 98% for binder course and wearing course, respectively, of average Marshall bulk specific gravity for each days production unless otherwise directed by the Director of works or his representative.

11. Any mix that becomes loose, broken, mixed with foreign material, or which does not conform in all other respects with the specified requirements, shall be removed, replaced with suitable materials and properly finished.

e) Test For Bituminous Pavements1. Minimum Tests Required

Work item Tests at Source of material Frequency of tests

Tests at road site Frequency of tests

1- Materials used in Asphalt mix (at Batching plant)

1- Specific gravity and water absorption2- Abrasion test

3- Chert content 4- Clay lumps and friable materials5- Flaky and elongayed particles6- Soundness

- Test for each source

- When materials quality changes - As requested

2- Materials used in Asphalt mix ( from hot bins)

1- Gradation

2- Specific gravity and water absorption 3- Plasticity index4-Sand equivalent5- Stripping with asphalt

- Test for each source- when materials quality changes

- As requested


Work item Tests at Source of material Frequency of tests

Tests at road site Frequency of tests

3- Asphalt mix design (At batching plant)

1. Complete mix design in accordance with American Asphalt Institute (MS2) 2. Loss of stability

-For each project-When materials quality changes -When results are not consistent with the mix design results - As requested

4- Asphalt At Batching plant

1- Stability 2- Flow3- Extraction (binder content and gradation)

4- Air voids 5- Voids in mineral aggregates6- Daily Marshall density

- Test each 3working days- Test for each batching plant - As requested

Behind spreader1- Stability 2- Flow3-Extraction(bindercontent andgradation 4-Air voids 5- Voids in mineral aggregates6-Marshall density

-Test each working day - Test for each batch- As requested

7-Loss of Stability - Once a week- As requested

7- Road density and thickness(after final compaction

- Test each 200 lin.m. per lane

- As requested

8-Loss off stability

- Once a week - As requested

2. The Marshall bulk specific gravity shall be determined in accordance with AASHTO T 166 or AASHTO T 275. The Marshall specimens shall be prepared from the same material used in construction, taken from samples of fresh bituminous mix at the mixing plant or from trucks delivering mix to the site. Oven heating for up to 30 minutes to maintain the heat of the sample is permissible.

3. The bulk specific gravity of the mix as placed and compacted in situ shall be determined from 100 mm nominal diameter core samples, or slab samples cut from compacted layer on the road at locations designated by the Director of works or his representative who may require additional tests to determine limits of areas deficient in density, or for recheck.

4. Samples for in situ bulk specific gravity determinations shall be taken in sets of 2 from each pavement location. Minimum frequency of sampling for each bituminous layer shall be one set/lane/500 m, with a minimum of one set per day of placing bituminous layers.

5. The Contractor shall, cut the samples with an approved core drill in the presence of the Director of works or his representative. the equipment shall be capable of cutting the mixture without shattering the edges or otherwise disturbing the density of the specimen. The contractor shall fill and compact all test holes at his own expense.

f) Surface Tolerances1. The fully compacted and completed bituminous course shall conform to the lines, grades and cross

sections as shown on the Drawings.2. The elevations of the finished course shall be checked by the Contractor in the presence of the

Director of works or his representative at maximum intervals of 25 and at intermediate points as directed.


3. When the finished surface is tested with a 3 m long straightedge, placed parallel to, or at right angles to the centerline, the maximum deviation of the surface from the test edge between any 2 contact points shall not exceed the tolerances specified for each type of bituminous course laid.

4. All areas which exceed the specified tolerances shall be corrected by removing the derective sections of bituminous course and reconstructing them or, if approved, by adding new material and recompacting and finishing to the specified standard or increasing the thickness of the succeeding course.

5. The tolerances specified for evenness of finished surfaces for all types of bituminous course, shall not invalidate the tolerances specified for construction thickness and elevations of such courses.

g) Determination of Thickness of Course1. Cylinder core samples shall be taken as specified for in situ bulk specified gravity core samples.2. Thickness of bituminous course shall be determined by average caliper measurement of cores,

rounded upwards to the nearest mm.3. Paved sections to be measured separately shall consist of each 300 lin. m section in each traffic lane.

The last section in each traffic lane shall be 300 m plus the fractional part of 300 m remaining. Other areas such as intersections, entrances, etc. Shall be measured as one section and the thickness of each shall be determined separately. Small irregular unit areas may be included as part of another section.

4. One core shall be taken from each section by the Contractor at approved locations and in the presence of the Director of works or his representative. When the measurement of the core from any paved section is not deficient by more than 5 mm from the specified thickness, the core will be deemed to be of the specified thickness as shown on the Drawings.

5. When the measurement of the core from any paved section is deficient by more than 5 mm but not more than 20 mm, 2 additional cores spaced at not less than 100 m shall be taken and used together with the first core to determine the average thickness of such section.

6. When the measurement of the core from any paved section is less than the specified thickness by more than 20 mm, the average thickness of such section shall be determined by taking additional cores at not less than 5 m intervals parallel to the centerline in each direction from the affected location until, in each direction, a core is taken which is not deficient by more than 20 mm. Exploratory cores for deficient thickness will not be used in average thickness determinations.

7. Any deficiencies in the total thickness of bituminous courses shall be subject to a proportional reduction in the area of (wearing) course measured for payment. Alternatively, the Contractor shall construct all at his own expense, a wearing course overlay, if practicable in the judgement of the Director of works or his representative. Any such overlay shall be a minimum of 40 mm compacted thickness and to the specified standard of the course it is overlaying.

8. If the deficiency in total asphalt layers thickness is from 0 -3 mm, full payment will be made, on condition that deficiencies are not found in more than 10% of the total project. Deficiencies exceeding 3 mm shall be left to the substantial handing -over procedure.

h) Measurement Bituminous course shall be measured by squ.m for furnished, paved compacted, tested and

approved areas placed according to drawing. Any correction, tests, samples, etc. shall not be measured for direct payment.

16.4Bituminous Binder And Wearing Courses16.4.1 ScopeThese works shall consist of furnishing materials, mixing at mixing plant, spreading and compacting bituminous binder and wearing course on an approved aggregate base course as and where shown in the Drawings.

16.4.2 Materials1. Materials shall conform with relevant requirements of section” Materials” mentioned before.2. Unless otherwise shown on Drawings, bitumen for binder and wearing course construction shall be

60/70 penetration graded bitumen.

16.4.3 Job Mix And Project Mix:1.The Job Mix formula shall be established by the contractor in accordance with the procedure and

requirements of section “ Bituminous Course” mentioned before.


2. The Job Mix for bituminous binder and wearing courses shall conform to the following composition limits, as shown in Table:

a) Job Mix Requirements To Bituminous CoursesProperty Medium-Light

Binder WearingMarshall Stability at 60c (kg) 800 900Flow (mms) 2-4 2-4Voids in Mineral aggregate (WA)

13(-1) 14(-1)

Air Voids (%) 4-5 3-5Stiffness (kg/mm) 400 (Min)* Loss of stability (%) 25 (Max)Asphalt Content (% in weight) 4.5-6 5-7

This test to be carried out in accordance with AASHTO T 165-82. After the Job Mix Formula has been established and approved, all subsequent mixes shall

conform to it within the allowable tolerances.

b) Equipment:Plant and equipment for mixing, hauling, placing and compacting bituminous binder courses and wearing course materials, shall conform with the relevant requirements of section “ Bituminous Course”.

c) Surface Preparation:Preparation of surface upon which bituminous binder course and the bituminous wearing course mixes are to be laid, and the use of prime coat, shall be appropriate to type and condition of such surface and shall conform with the relevant requirements of section "Bituminous Courses".

d) Delivery, Spreading And FinishingGeneral :

The delivery, spreading and finishing of bituminous mixes for binder and wearing courses shall conform with the relevant requirements of Section “Bituminous Course” and with the following particular requirements.

Rollers:1. Initial breakdown rolling shall be carried out by use of 2 dual-drum steel-wheeled rollers each of

minimum weight 7,000 kg. These rollers shall be purpose made for compaction of hot bituminous courses.

2. Intermediate rolling shall be carried out by of at least 2 self-propelled, tandem pneumatic smooth-tired rollers each capable of exerting contact pressures of up to 690 kN/sq.m (100 psi) and ballast- adjustable to ensure uniform wheel loading.

3. Final rolling shall be carried out by use 2, 2-axle tandem, steel-tired rollers each of minimum weight 10.000 kg, capable of exerting contract pressures of up to 65 kg/cm (350 Ib/in.)

Standard of Compaction:The compacted density of the bituminous wearing course shall be not less than 98% of the average Marshall bulk density for each day’s production.

e) Sampling And Testing Sampling and testing shall conform with the relevant requirements of Section “Bituminous Course “.

h) Surface Tolerances1. Surface tolerances shall conform with the relevant requirements of Section “Bituminous Course “,

and with the following particular requirements.

2. The tolerances on elevations of the final bituminous wearing course surface shall not be greater than 10 mm.


3. When the finished wearing course surface is tested with a 3 m long straightedge, placed parallel to, or at right angles to the centerline, the maximum deviation of the surface from the testing edge between any 2 contact points shall not exceed 5.0 mm.

i) Determination of Thickness1. Procedures for determining the average compacted thickness of bituminous binder and wearing

course shall conform with the relevant requirements of Section ” Bituminous Courses” and the following particular requirements.

2. Cores for thickness measurements of binder course shall be used to determine if changes are necessary in the constructed thickness of the wearing course and thickness deficiencies in the binder course.

j) Measurement1. Bituminous binder course and bituminous wearing course shall be measured by sq.m. of mix finished,

spreaded, compacted, completed and accepted. Measurements shall be of the areas and thickness as shown on the drawings.

2. Deficiencies in thickness of wearing course shall, unless an overlay is constructed at contractor's expense, result in proportion only of the wearing course area being measured for payment. Proportions shall be determined in accordance with the thickness deficiencies and area proportions mentioned in section " Bituminous Course".

3. Bituminous Prime coat and Tack coat shall be measured as prescribed in "Bituminous Prime and Tack Coats".

4. All other items shall not be measured for direct payment as prescribed in section " Bituminous Course".


17.CONCRETE BLOCK PAVING

17.1Form Of ConstructionConcrete block surfacing shall consist of precast concrete blocks on a laying course 50mm thick sand on sub-base on subgrade.

17.2Test StandardsUnless stated otherwise, testing of subgrade, sub-base materials and workmanship shall be carried out in accordance with BS 812 and BS 1377, Laboratory Maximum Dry Density tests shall be in accordance with Test 13 of BS 1377 and liquid limit shall be determined in accordance with test 2A or 2B of BS 1377, In-situ C.B.R testing shall be in accordance with Test 15 BS 1377.

17.3SubgradeSubgrade shall consist of approved granular material compacted to 95% of the laboratory maximum dry density , The C.B.R value shall not be less than 95% ( in case of supplying imported fill material )

17.4Sub-Base MaterialSub-base material shall be crushed rock or similar hard material or naturally occurring gravel which is clean and free from organic matter, clay balls and other deleterious materials, The materials shall comply with the following grading :-

sieve size (mm) Percentage by weight Passing

75 10037.5 85-10010 40-705 25-450.600 8-220.075 0-10

The total acid-soluble sulphate content ( as S03 ) (BS 812 Test 118) shall not exceed 2% by weight, The total acid-soluble chloride content (as NaC1) (BS 812: Test 117) shall not exceed 3.3% by weight.The laboratory C.B.R value shall be a minimum of 60% at 95% of the laboratory maximum dry density after soaking for 96 hours.

Material for Sub-base shall have physical Properties which do not exceed the following test value:Liquid limit 25%Linear shrinkage 3% Plasticity index 6%Stone size 50mmAggregate crushing value 25%Water absorption 2%Flakiness index 35%Elongation index 35%Soundness( 5 cycles ) ( ASTM C 88 ) 15%

The sand equivalent shall not be less than 45 when tested in accordance with ASTM D24419.

17.5Laying Compaction Of And Testing Sub-BaseSub-base material shall be spread evenly and compacted in layer not exceeding 200mm compacted thickness to obtain a well-bound surface finish, loose or segregated areas shall be made good by addition of lines or by removal and replacement of the material as directed.Compaction shall be carried out by approved plant operating on the material at an approved moisture content until a dry density of not less than 100% of the laboratory maximum dry density is achieved. One density test shall be carried per 250m2.


The sub-base shall be laid to the level shown on the Drawings the rate of one set of tests for each 500m2. The set contains of 3 sand cones tests.The edge restraints to the paved area shall be installed before the laying course.The sand shall be laid at a uniform moisture content and carefully screened to form a smooth compacted surface.

The profile of the laying course before compaction shall be similar to that of the finished surface, The maximum deviation from the design levels shall be + 5mm. The laying course shall be placed to a level which takes into account the compaction which occurs during vibration of the blocks ; the amount of this compaction shall be determined by trials prior to commencement of surfacing.

17.6Surface CourseThe surface course shall consist of approved precast concrete blocks complying with BS6717: part 1. The concrete constituent shall comply with the requirement of the concrete specification given elsewhere.Additional requirements are contained in the following Clauses of this specification.

17.7Fine AggregateFine aggregate shall not contain more than 25% by weight of soluble calcium carbonate in either the fraction retained on or the fraction passing a 600 micron BS sieve.

17.8Coarse AggregateCoarse aggregate shall be material retained on a 4.75mm BS sieve, the nominal maximum size shall be 10mm, The grading shall comply with BS 882, Table 4 so that when mixed with sand and cement a high density concrete is produced.

17.9Sampling And Testing Sampling and testing of blocks shall be carried out in accordance with BS 6717. Sampled blocks shall be subjected to all the tests covered by appendices A and B of BS 6717.

If any of the 20 test blocks do not comply with the requirements for dimensional accuracy the whole consignment may be rejected.

17.10Test For Compressive StrengthTesting of blocks for compressive strength shall be carried out in accordance with appendix B of BS 6717 except that blocks shall be soaked for 24 hours in fresh water at 20 degrees centigrade immediately prior to testing Fresh plywood packing shall be used for each specimen tested.

17.11Water AbsorptionBlocks shall be tested for water absorption , The test shall be based on that specified in BS 1881 : Part 122 and the maximum acceptable limits for water absorption.2.5% absorbed after 10 minutes.5.0% absorbed after 24 hours.

The acceptable limits for water absorption may be required to be varied to achieve the minimum absorption compatible with the aggregate approved for use in the paving blocks.

17.12ColorThe color of blocks shall be uniform and as detailed on the drawings or as directed, Samples of each different color shall be submitted for approval.

17.13Block LayingBlock laying shall commence at angles to the main pavement axis starting at one end of the area.Interlocking blocks shall be laid in a herringbone pattern at 45 degree to the main pavement axis or other pattern as approved or directed, Rectangular blocks shall be laid in patterns as directed using different colors if directed.Blocks shall be laid on the sand laying course so that blocks already laid are not distributed, Blocks shall be placed to fit closely together, the width of joints shall not exceed 3mm.


Dimensional accuracy, uniformity of joint gaps, alignment and squares shall be checked after laying the first three rows of blocks and thereafter at regular intervals.If joints begin to open, the blocks shall be knocked together using a hide mallet

.17.14Edge Details

Special edge blocks shall be used on all edges of interlocking block paving which are parallel to or perpendicular to the main pavement axis, Where the shape or dimensions of paved areas preclude the use of special or standard blocks on all edges, cut blocks shall be used , Blocks shall be cut to suit, using a mechanical block splatter, In-situ concrete shall not be used to make up to edge restraints.

17.15Compaction By VibrationBlocks shall be compacted to the required levels using a plate vibrator as each area of 20 m2 is laid.The plate vibrator shall have a plate area of 0.2 to 0.3m2 and compaction force of 9 to 16KN. Two passes of the plate vibrator shall be made in two directions at 90 degrees to each other.

17.16Filling JointsJoints shall be filled by brushing in line dry sand with a particle size up to 2mm and maximum sulphate content (as S03) of 0.4% by weight a further pass of the plate vibrator shall be made in each direction.Weed killer have to be mixed with residual qualities with the sand used for sealing the joints.The vibrator shall not be used within 1m of an unrestrained edge. Paving shall not otherwise be left uncompleted overnight.

17.17Laying ToleranceThe finished surface level shall be within 5mm of the design level and the maximum deviation within the compacted surface, measured by a 3m straight edge shall not exceed 5mm. The level of any two adjacent blocks shall not differ by more than 2mm.

17.18Laying CourseThis is a 50mm thick layer of clean sharp sand containing not more than 3% silt and clay. and with not more than 10% by weight retained on a 5mm sieve. For best results, the moisture content of the laying course sand should be within 1% of the optimum, as determined be Test 12 of BS 1377. The sand should be spread over the area to be paved. The actual thickness will vary according to the tolerance of the Sub-base layer. Sub-bases Specification are allowed a tolerance of 25mm.

17.19Compressive StrengthThe average compressive strength of the Block on delivery when sampled and tested in the manner described in BOQ shall not be less than 40N/mm2 in wet condition.
