access engineering plc - training presentation

05/03/2023

REHABILITATION & IMPROVEMENTS TO COLOMBO – KANDY ROAD SECTION FROM

KADAWATHA TO NITTAMBUWAACCESS ENGINEERING PLC

BOMBUWALA B.G.A.EN 14 5011 80

05/03/2023 ACCESS ENGINEERING PLC

Access Engineering Ltd.

• VISION– To be the foremost Sri Lankan business enterprise in value

engineering• MISSION

– To meet the challenges in the development of multi sector civil engineering projects, providing innovative solutions whilst developing long term progressive relationships with all our stakeholders

http://www.accessengsl.com


PROJECT DETAILSProject: Rehabilitation and Improvement of A001

Colombo - Kandy Road Section from Kadawatha – Nittambuwa.

Contractor: Access Engineering PLC

Consultancy: Road Development Authority

Project Value: Rs. 7.7 BillionProject Duration: 18 months Project Length: 23 kmProgress at the time of training: 25 months (7 km)Current Progress: 34 months (9.5 km)The rehabilitation includes improvements of road,

pavements and bridges.


TRAINING SCHEDULE

TASK NAME DURATION (weeks)

Earthworks 3

Structures 3

Drainages 1

Culverts 2

Precast yard 0.5

Laboratory (QA/QC) 2

Finishes 0.5

Quantity Surveying 1.5

Bridge work & Piling 2

Total 12.5


Earthworks


Cross Section of Roadway

7.4 m 7.4 m


MAIN FEATURES OF THE REVISED PROPOSAL

ITEM DESCRIPTION

Carriageway Four lane, 14.8m wide(2*7.4m)

Shoulders Hard shoulder 0.6m(2*0.3m)Soft shoulder 2.4m(2*1.2m)

Composition of Carriageway

Overlay sections40mm thick Asphalt Wearing Course

Surfacing, 80mm(average) thick AsphaltBinder Course(includes regulator for profile

correction)

Widening sections

40mm thick Asphalt wearing course and 80mm(average) thick Asphalt Binder Course

with a325mm thick dense graded base course and a 350mm thick soil sub-base and capping layer

and sub grade as per requirement(Binder thickness varies from section to section).


Detailed Cross Section of Roadway


EARTH WORKS – ROCK FILLING & EMBANKMENT FILLING

An embankment consists of 4 parts which are:• Rubble layer• ABC layer• Geo-textile membrane• Soil layer First the area was prepared by removing existing soil and then Rubble layer was

laid up to 700mm height and then ABC was laid up to 100mm. After putting membrane, the layers were compacted using 10-tonne compactor.


EARTH WORKS – ROCK FILLING & EMBANKMENT FILLING

After compacting, soil layers were laid and compacted one by one up to 1250mm(250 *5 layers).


EARTH WORKS – SUB-BASE AND BASE

Then sub-base bottom layer is filled up to about 200mm and sub-base top layer is filled up to 150mm(total 350mm) heights.


EARTH WORKS – SUB-BASE AND BASE

• After that, Aggregate based course(ABC) first layer with 180mm thickness and

quarry dust were laid and compacted using Grader.


Dense Graded Aggregate Base Coarse(ABC)• Provides uniform and stable foundation for the layers placed on top.• Firmly bonded with the asphalt binder and wearing courses.• Procedure for ABC top laying,

– First we had to install pegs in each chainage with additional 300mm space from new EOP and from the end of the design offset of the new road.

– Design level + 45mm was marked in the pegs by using level machine.– After that we had to provide 2 roller passes using roller.– Again we have to check the levels in each chainage and we have to install pegs from the

offsets of EOP, 6m from the center and 8.3m from the center.– Levels were given to the peg as design level + 14 mm and scratch ABC using grader.– After that 2 roller passes was provided.– Again we had to check the levels and we had to cut or fill ABC where necessary.– At last we gave 4 roller passes and checked the levels.


Dense Graded Aggregate Base Coarse(ABC)

Unloading

Spreading using Motor Grader

Providing roller passes

Doing correction to necessary places

Giving Levels


EARTH WORKS - SHOULDER• Constructing a soft shoulder.• Soil was compacted above the sub base for the shoulder for a 1.2m width. The

total height of the layer was 325mm.• At first, a 250mm layer was put and compacted by the 5-tonne compacter with 6

passes to a 200mm layer. Then a 150mm second layer was put and compacted to a 125mm layer. The cutting edge was 8.35m from center of the new road.

Backfilling by hand Backfilling by Bob-cat Compacting using 5-tonne


Structures


MAIN FEATURES OF THE REVISED PROPOSAL


CULVERTS AND DRAINAGES - DRAINAGES

Constructing a line drainage in a highway and its importance. Site was cleaned and setting-out was carried by tape measurements to locate line

drainage path. Excavation levels were marked using Dumpy leveler. 50mm screed concrete was poured and on top of it. Base and walls of type 1 drain was constructed using GR.25 concrete. Cured previous concrete. Light weight cover slabs were placed. Hume pipes were placed between drain and culvert.


CULVERTS AND DRAINAGES - DRAINAGES

Excavating Formworking & concreting Cover slab placing


CULVERTS AND DRAINAGES - CULVERTS

Constructing a Box culvert in a highway and its importance. Existing road was cleaned and setting-out was carried by Total station & tape

measurements to locate Box culvert path. Excavation levels were marked using Dumpy leveler. Procedure:• Excavating and demolishing of existing culvert if there is any.• 75mm thick screed concrete (C15 (20)) pouring.• Formworking, reinforcing and concreting base (Grade 30 (20) - Ready mixed).• Formworking and reinforcing for wall plus lower hunch. • Formworking for slab/deck plus upper hunch.• Cleaning and De-watering.• Concreting wall, slab/deck plus hunches. (Grade 30 (20) - Ready mixed).



Excavating & demolishing Screed pouring Formworking, reinforcing & concreting of base



Formworking & reinforcing of walls +

slab

Concreting of walls + slab Levels checking


LABORATORY WORK Lab tests were done under following categories:• Asphalt

Extraction testMarshall testCore cutting testAsphalt stability and flow test

• SoilSand cone testProcter compaction testCBR testDCP testAtterburg Limit test

• ABCAIV testLAAV testSieve analysis test


LABORATORY WORK• Tests done to check the soil conditions and soil properties,

TEST NAME APPARATUS TEST METHOD

Atterburg Limit tests

Liquid Limit Liquid Limit apparatus AASTHO-T-89 , T-90

Plastic Limit - AASTHO-T-89 , T-90

Sieve analysis test

Sieves (mm)Shoulder:20, 5, 2.36, 0.600, 0.075, pan. Sub base:20, 5, 1.18, 0.300, 0.075 pan.

BS 1377 - Part 2

Modified proctor compaction test Mold , Hammer , Oven BS 1377 Test 13 / AASHTO T-

1804-day soaked CBR at 95% MDD

(Modified)Mold, Hammer, Gauge, CBR test machine

AASHTO T-193


LABORATORY WORK• Apparatuses

COMPRESIVE TESTING MACHINE CBR TEST MACHINE

AUTOMATIVE MARSHALL COMPACTOR



CENTRIFUGAL ASPHALT EXTRACTION APPARATUS SPECIFIC GRAVITY FRAME

MOTORISED MARSHALL TEST MACHINE



LOS ANGELES MACHINELIQUID LIMIT TEST APPARATUS


QUANTITY SURVEY WORK Conditions of Contract, Specifications, Bidding documents, Price fluctuations and

so on. As works I had done: taking quantities from drawings, calculating price fluctuations, checking drawing levels on CS and LS drawings.

Some of the documents I referred were:


QUANTITY SURVEY WORK Codes of practices, standards and material references:• Sri Lankan standards• British standards• AASHTO Publications (2002 Edition)• ASTM Publications• FIDIC Documents• HMSO Publications• ICTAD Publications• TRL Publications• DIN


BRIDGES Constructing a pile using percussion boring method. Coffer dam was constructed. Jumbo bags, filled with soil were placed around the

embankment in order to stop collapsing. To reduce the block of the flow, we place Hume pipes under the embankment at the beginning.

Procedure:• Locating bridge pile center using Total station.• Excavating for temporary cover.• Placing temporary cover and checking level and position at top.• Setting pile Tripod.• Placing rectangular case.• Placing chisel/cutter.• Combining a rod with the chisel and start boring till meeting bedrock.• Do socketing for 1m.• Flushing-out hole with Bentonite.• Inserting Reinforcement mesh.• Concreting pile.


BRIDGES

Jumbo bags filling with soil

Placing around embankment Setting out by TS


PILING

Placing tem. cover & level checking Setting out Tripod Soil boring


PILING

Taking samples Flushing out Putting reinforcement mesh & concreting


Health and Safety

• Access Engineering PLC, operating in infrastructure development field, shall provide and maintain high standard of health & safety for all its employees and general public who may be affected by the operation

• Creating awareness by training, sharing information & supervision and maintaining preparedness to meet health & safety emergencies to ensure a safe and healthy working environment at all offices and sites.


Environmental Policy

• Access Engineering PLC recognizes that in carrying out its activities it has a responsibility to customers, employees and the general public to minimize environmental impacts. The environmental policy of Access Engineering is to:

• Ensure compliance with all applicable legal and other requirements, which relate to its environmental aspects.

• Promote environmental awareness and commitment to the policy amongst all employees and Stake Holders through training, and communications to encourage suppliers and subcontractors to apply sound environmental principles.

• Avoid the wastage of materials, water and energy by paying careful attention to their use.• Prevent pollution and minimize environmental disturbance from our activities.• Apply continual improvement by reviewing the environmental aspects related to our

activities by setting appropriate targets and objectives for improving performance.