concrete repairs

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Concrete Repairs Rev. 0

CONCRETE REPAIRS

WM # 65

OriginatorName: Date:Signature:

Name:Date:Signature:

Safety DepartmentName: : Date:Signature:

Design Department: Name: Date:Signature:

Construction Department:Name: Date:Signature:

EnvironmentName: Date:Signature:

Quality AssuranceName: Date:Signature:

Casting YardName: Date:Signature:



AREA MANAGERS or SuperintendentsSignature Date Signature Date

QA Department

Name: Date: __________________

Signature: ____________________________________

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PREFACE:This work method has been written as a specification for concrete repairs during the Construction of the Vancouver Elevated Guideway Project.

1.0 PURPOSE

1.1 To define the responsibilities and describe the method and documents to be used to perform concrete repairs during the construction of the Vancouver Elevated Guideway Project

2.0 SCOPE

2.1 This Work Methods shall apply to all concrete related repairs on the Vancouver Elevated Guideway Project including repairs to both precast and cast-in-place concrete elements.

2.2 Repairs will be done on several categories of concrete placement defects. These defects and the manner in which they are addressed are as follows:

Surface or Non-Structural Defects

Structural Defects:

Rejection Defects:

2.2.1 Surface and Non-Structural Defects

This type of defect includes:

- Bug Holes- Honeycomb, Spalls and Surface repairs up to 50 percent of

specified concrete cover- Crack limits (non-structural)- Broken shear keys- Miscellaneous holes in the concrete structure- Anchorhead recesses, P.T. blockouts and grout vents

2.2.2 Structural Defects


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- Honeycomb, voids, spalls and cavities beyond 50 percent of specified concrete cover.

- Structural cracks to be determined by consultation with the Engineer.

- In general, any kind of damage affecting the structural integrity the durability and the aesthetic intent of the precast segments or cast-in-place elements.

3 DEFINITIONS

4 RESPONSIBILITIES AND AUTHORITIES

4.2 The Precast Yard Manager is responsible for the day to day managements of all work performed at the Port Moody casting facility including subcontracted work such as reinforcement supply and fabrication and concrete production. He is the final responsible individual for the quality of the end product.

4.3 The Precast Yard Superintendent is responsible for the supervision, training, cycling, quality controls, survey alignments, crews, foremen and supervisors involved in the manufacture of the precast segments. This includes ensuring other trades involved coordinate to the cycle time (i.e. reinforcing steel, post-tensioning, concrete pouring, crane operations).

4.4 The Area Superintendent is responsible for the direct field application of all setup and casting activities including form assembly, rebar and P/T assembly. He is responsible for quality as it relates to this portion of the work.

4.5 The Senior Precast Engineer/Senior QC Engineer is responsible for the preparation of the necessary Work Method and Procedures for precasting of the segments and coordination between the Survey Department, the Safety and Risk Department, the QA Department and other relevant disciplines. The Survey Department and QC Department including Field Engineers report directly to him and through them he is responsible for the overall Quality Control under the scope of this Work Method. He is authorized to stop work if execution is not meeting QC requirements.

4.6 The Surveyors are responsible for the execution of all survey activities under the scope of this Work Method.


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4.7 The Bed Supervisors are responsible for the direct field applications of all casting activities, including form assembly, rebar, P/T assembly, and placing and curing of concrete. Each supervisor is responsible for quality as it relates to his portion of the work.

4.8 The Concrete Foreman is responsible for all precast concreting operations, from placing to curing, repair and patching operations, storage and shipping. He is responsible for quality as it relates to this portion of the work.

4.9 The Field Engineers/QC are responsible for facilitating and recording that the segments fabricated in the beds for which they are responsible are fabricated according to the structural and quality requirements of the Contract Documents.

4.10 The Quality Assurance Manager in co-ordination with the Construction Area Managers is responsible for initiating Work Methods and Inspection and Test Plans covering all construction aspects of the Project. He shall initiate a Preparatory Meeting between all parties involved in order to carry out appropriate reviews of Work Methods and Quality Procedures. He shall confirm and record by means of inspection and audit that the work conforms with plans and specifications.

4.11 The Manager of Design is responsible for reviewing the Method Statements and Inspection and Test Plans for conformance to plans and specifications. He is directly responsible for the conveyance of information and technical assistance including supply of shop drawings and bar lists.

4.12 The Manager of Safety is responsible for reviewing Safety Instructions to ensure safe working conditions for the work under the Work Methods.

4.13 The Environmental Coordinator is responsible for reviewing the Method to ensure that work is planned in such a way as to minimize the impact upon the environment and shall comply with all environmental legislation, regulations, permits, licenses, agreements, and rules applicable to the Project.

5 PROCEDURE

5.1 Scope

All managers and supervisors shall ensure that the work described herein will be completed in a manner consistent with the requirements of the Contract Drawings and Documents, the Project Safety Program and the applicable codes and regulations.


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5.2 Classification and Documentation of Defects

Immediately after the formwork is stripped off, the Superintendent and SAR Transit QC Engineer must make a visual check of the newly poured element.

Any kind of deficiency mentioned in Section 2.2 of this document must be documented by the SAR Transit QC Engineer on the appropriate Inspection Form on which will be noted: pier number, segment, casting date, mix design, repair location, size and if necessary, pictures or sketches.

During Guideway Construction:

In the case of a structural defect being reported by the QC Engineer,an NCR (Non Conformance Report) on a CDR (Construction Deficiency Report) will be issued to the QA Engineer. the QA will inform the Design Department and the NCR or CDR disposition process will commence. See QMP and .The Structural Engineer, JMI, may be involved in the disposition process.

A representative of the Engineer will inspect the piece within 24 hours after receipt of the NCR, evaluate the severity and significance of the damage and determine what kind of repair must be done.

After evaluation, The Design Department will review with the Engineer if the damage(s) must be covered by an NCR on a CDR.

NCR – Major structural defects or repairs not covered by this document and defects requiring immediate repairs prior to PT stressing, requires a disposition by the Engineer.

Structural defects that can be repaired at a later date and for which repair procedures are in place in this document. Will receive an NCR for the first occurrence but all subsequent similar repairs will be handles with a CDR.

A remedial procedure will be issued by the SAR Transit Senior Engineer to completely outline each major repair, including sketches when required.

5.3 REPAIR CRITERIA


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5.3.1 Surface Deficiencies

Such as:

Honeycombs Bugholes Small cavities Small voids Surface cracks Spalled concrete

that do not exceed 50 percent of the specified concrete cover, or extend to any post tensioning system within tolerance, are considered to be NON STRUCTURAL DEFECTS and may be repaired without review by the Engineer. Also included in this list are normal construction repairs such as infilling tie holes, core holes, and miscellaneous holes left during erection, anchor head recesses and repair of shear keys.

Repair Criteria: In accordance with the criteria developed in Section 6.0 of this document.

Methods of Repair: Developed in Section 5.4.2 of this document.

5.3.2 Structural Deficiency or Damage

Structural deficiencies or damage is defined as the following:

extends beyond 50 percent of the Specified Concrete Cover

exposes reinforcing steel crack of major size (see Section 5.4.2.3) located in a bearing area exposes any part of he post tensioning system or occurs

in the deck portion of the segment

Repair Criteria: In accordance with the criteria developed in Section 6.0 of this document.

Methods of Repair: Developed in Section 5.4.3 of this document.

5.3.3 Proposed Repair Materials

For the selection of products and type of repair, seeAppendix 1


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For the repair material application temperatures, see Appendix 3

For crack limit and treatment, see Appendix 4

Supplier ProductsMaster Builders – Emaco R300, T415, T430, S88-CA, S77-CR, S66-CR, Set

45, SCB Concresive 1360, Concresive 1442Sika Inc. Sikadur 52 Injection Resin, Sikadur 31 Hi-Mod Gel,

Sikadur 32 Hi-Mod Bonding Adhesive CAPPAR Caprock LT, Capbond EX, Capweld 424Hydrozo Silane 100Devoe Coating Bar Rust 236Carboline Carbo Zinc 11Meadows Sealtight CS-309 Curing CompooundBurke Burke NS Segmental Epoxy Bonding Agent

NOTES:

1. During Guideway Construction: All Materials not mentioned on the above list that are to be used for repairs are to be approved by The Design Department and the Designed. Prior to submittal, confirm that all acceptance criteria in Chapter 1 of this document have been met.

2. All repair materials are to be used in strict accordance with the manufacturer’s data sheets. Where usage deviates from the manufacturer’s data sheets, written consent is required from the manufacturer’s engineer with back up of prior usage in similar conditions and the expected long term durability duration of the product.

5.4 REPAIR PROCEDURE

5.4.1 General

This Section is applicable to repair procedures using cementitious repair products only, unless exempted by the manufacturer’s data sheets.

The following is a list of criteria that must be followed when completing a repair:

1. When there are a large number of minor imperfections in a specific area, the repairs must be done in several phases to assure that the concrete is in a wet/damp condition when the repair material is placed.


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2. Preparation of the concrete surface is to be done using light chipping equipment, sandblast or water blast to obtain a minimum 3 mm or 5 mm amplitude as required. Do not use bush hammer methods. All unsound bruised concrete to be removed. Water blast is the recommended preparation method.

3. Substrate is to be free of all laitance, curing compound, oil, dirt, dust and debris. Pressure water wash is the recommended cleaning method.

4. If pressurized air is used to clean a repair area, it must be free of oil or any spoiling material.

5. Ensure that the substrate is a wet/damp condition, unless exempted by the manufacturers data sheet. There is to be no standing water at the time of application of repair material.

6. Application temperatures for repair materials are noted in Appendix 3.

7. Apply bond slurry where required and place repair material before the slurry sets.

8. Mix and apply the repair material in strict accordance with manufacturer’s specifications.

9. Do not exceed the recommended water/cement ratio.

10. When wooded forms are used (other than water tight form plywood), strip prior to 16 hours and apply approved curing compound, or wet cure.

11. All repairs materials require a compressive strength of 25 Mpa before the temperature of the repair material is allowed to drop below the recommended minimum (see Appendix 3).

5.4.1.1 Wet or Damp Condition

The surfaces are to be wet or damp prior to application with no standing water.

Suggested methods of keeping the substrate wet or damp:

-Portable spray tank or water hose,-Rags packed and kept watered in the recesses,-Watertight forms filled with water,


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-Sprinkler oscillating system or lawn garden hose that spray a mist-Running water from the top down

5.4.1.2 Self Saturation of the Concrete

(Applicable to minor surface repair and bug holes only).

**The only case where soaking and substrate preparation is not required is where the concrete repair is completed within the following guidelines:

1. All work, including stripping and application of repair material must be completed within 16 hours of pouring the substrate concrete,

2. The repair must be completed within two hours of stripping,

3. The substrate must be free of form oil, curing compound, or other debris, and,

4. Substrate temperature must be according to Appendix 3.

5.4.2 Surface and Non-Structural Defects

This category of defects includes superficial damages that affect the durability of the structure but do not affect the structural integrity of the structure.

5.4.2.1 Bug Holes

See Appendix 2 for bug holes classification.

Surface Preparation: To prepare the defect for repair, roughen the concrete surface to minimum amplitude of 3 mm by sandblasting, water blasting or light chipping hammer. Do not use a bush hammer.

The substrate is to be free of all laitance, curing compound, dirt, dust, oil or other debris. Pressure water wash recommended.

The concrete is to be wet or damp prior to application, with no standing water.

Prepare, saturate and heat substrate, mix and apply materials , finish and cure all repairs as per requirements and in strict accordance with the manufacturer’s data sheets.

Proposed Cementitious Repair Materials:


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1. EMACO R300 (can be used for feathering) (bond slurry required)

2. EMACO S88-CA (bond slurry required)3. EMACO T430 (bond slurry required)4. EMACO T415 (bond slurry required)

NOTES:1. Refer to Appendix 1 for the correct repair materials and

placing methods for each repair.2. Refer to Appendix 3 for temperature requirements.

Slurry Application: Bond slurry consists of 5L of potable water per 25 kg bag of Emaco product. Apply by scrubbing slurry material into the surfaces with a stiff bristle broom or brush. Do not allow slurry to dry before repair material is applies.

Curing: Two coats of curing compound should be applied in perpendicular directions within 15 to 30 minutes after the repair is complete or as soon as the surface cannot be marred by the application.

Proposed Curing Compound: (SEALTIGHT CS-309) (the application rate of the product is 4m² per litre, applied by spray or roller paint methods after initial set of the repair material).

Proposed Epoxy Repair Materials:

Cappar CAPBOND EX

Note: Cappar Capbond EX does not require wet/damp substrate conditions, bond slurry or curing.

Bug holes and small defects on the interior face of the approach segment may be repaired with the accepted approach segment epoxy bonding agent (See Appendix 8)

5.4.2.2 Honeycomb, Spalls and Surface Repairs up to Fifty Percent of Specified Concrete Cover

Surface Preparation: Edges must be squared and roughened to a minimum depth of 10 mm, all around the damaged area.

Prepare defect surfaces by sandblast, water blast or light chipping to exposed sound aggregate and roughen the concrete surface to minimum amplitude of 3 mm. Do not use equipment (bush hammer) or methods that could fracture the concrete or aggregates.


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The substrate is to be free of all laitance, curing compound, dirt, dust, oil or other debris. Pressure water blast recommended.

The concrete is to be wet or damp prior to application with no standing water.

Proposed Repair Materials:

1. EMACO S77-CR (no bond slurry required)2. EMACO S77-CR extended with stone (no bond slurry

required)3. EMACO S88-CA (bond slurry required)4. EMACO S88-CA extended with stone (bond slurry

required)5. EMACO T415 (bond slurry required)6. EMACO T430 (bond slurry required)7. EMACO T415 extended with stone (bond slurry required)8. EMACO T430 extended with stone (bond slurry required)9. EMACO R300 (bond slurry required)10. EMACO S66-CR (bond slurry required), or,

NOTES:

1. Refer to Appendix 1 for the correct repair materials for size of repair and repair area orientation (horizontal, vertical, formed, etc.).

2. Refer to Appendix 3 for temperature requirements.3. Refer to manufacturers data sheets for correct materials and

placing methods.

During Guideway Construction: the Engineer must approve all other products.

Slurry Application: Bond slurry consists of 5L of potable water per 25 kg bag of Emaco product. Apply by scrubbing slurry material into the surfaces with a stiff bristle broom or brush. Do not allow slurry to dry before repair material is applied.

When it is not possible to keep the slurry moist use S77-CR (depths 6 to 40 mm)

5.4.2.3 Crack Limit

During Guideway Construction: Cracks, whatever the origin, thickness or depth, could be of the utmost importance and have


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to be addressed by the Engineer. All cracks must be noted on an IF-83C form (See Appendix 7).

For crack limits and method treatment, see Appendix 4.

The type of epoxy to be used (low, medium or high viscosity) as well as the general repair procedure and equipment should be determined by the manufacturer’s representative.


1. SIKADUR 52 Injection Resin for injection and gravity feed,

2. SCB Concressive 1360 for gravity feed, and, 3. Cappar Capweld 424 for injection only.

NOTES:1. Refer to Appendix 1 for the correct repair materials for

size of repair and repair orientation (horizontal, vertical, formed, etc).

2. Refer to Appendix 3 for temperature requirements.3. Refer to manufacturers data sheets for correct material

and placing methods.

Injection ports should be placed at 300 mm maximum spacing. Note that the spacing of the injection ports should be similar to the depth of the crack. The outside face of the concrete is sealed and the two-part epoxy is injected under pressure following the manufacturer’s specification.

To Seal the Surface for Injection: The proposed product to seal the outside face of a crack for injection of SIKADUR 52 is SIKADUR 31 Hi-Mod Gel and the accepted product to seal the outside face of a crack for injection with CAPWELD 424 is CAPBOND EX.

5.4.2.4 Broken Shear Keys (on Precast Matchcast Elements)

Generally, repairs on the matchcast face can only be performed after the joints have been completely closed at the erection site.

The most important shear keys are the web keys because they participate in the shear strength of the joints. Top and bottom slab keys are mainly for alignment and local shear transfer (top slab).


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Repairs to shear keys along the webs shall be made after the segments are erected.

On Cantilever Spans, when 25 percent or more of the shear keys in a web have been damaged or the remaining shear keys cannot effectively transfer the shear across the joint (as determined by the Engineer), then the damaged shear keys shall be repaired after the segments have been erected and stressed together, (first with the PT bars, then with the post tensioning tendons) and before placement of the next segment on the damaged side.

When the repair grout or mortar has reached the required compressive strength of 14 MPa, the adjacent match-cast segment can be placed in cantilever. However, the Engineer will review the location and magnitude of the damaged keys and notify the Contractor of the type of repair, if any, according to the number of shear keys in the area and stress calculation.

On span by span sections when 25 percent or more of the shear keys in a web have been damaged or the remaining shear keys cannot effectively transfer the shear across the joint (as determined by the Engineer), then the damaged shear keys shall be repaired after the segments have been erected and stressed together (with P.T. bars).

When the repair grout or mortar has reached the required compressive strength of 14 MPa, the span can be stressed with the post tensioning tendons. However, the Engineer will review the location and magnitude of the damaged keys and notify the Contractor of the type of repair, if any, according to the number of shear keys in the area and stress calculation.

Proposed Repair Materials: A proposed rapid strength repair mortar is EMACO T415 (bond slurry required) or EMACO 430 (bond slurry required), extended with 10 mm washed site stone.

NOTES:

1. Refer to Appendix 1 for the correct repair materials for size of repair and repair orientation (horizontal, vertical, formed, etc.).

2. Refer to Appendix 3 for temperature requirements.3. Refer to manufacturers data sheets for correct material

and placing methods.


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Slurry Application: Bond slurry consists of 5 L of potable water per 25 kg bag of Emaco product. Apply by scrubbing slurry material into the surfaces with a stiff bristle broom or brush. Do not allow slurry to dry before repair material is applied.

Usually, no repair is required when: 1. There is no more than the total volume of one shear key broken on any web, including damage to a female shear key, 2. The area is less than 75 cm² total on any joint face.

Preparation: To be done at casting yard prior to shipping the segments.


Proposed Curing Compound: (SEALTIGHT CS-309) (the application rate of the product is 4m² per litre, applied by spray or roller paint methods after initial set of the repair material).

5.4.2.5 Repair of Miscellaneous Holes Left During Precasting

5.4.2.5.1 Cylindrical Tie Hole with Plastic Deviator and Plastic Pipe Sleeve (If used)

Preparation: After the plastic sleeve is removed, the surface of the tie hole is to be roughened by reamer or sandblast.

Proposed Repair Material:

1. All tie holes (if used) can be plugged on both sides with conical precast concrete inserts (Appendix 6). These plugs are made out of the same concrete mix used for the reinforcing spacers, or,

2. Drypacked as noted in Section 5.4.2.5.3 of this document.

The plugs are epoxied tightly into the recess left by the temporary plastic connector with any of the approved segment epoxy bonding agents listed below. Ensure entire contact surface of the plugs are sealed with epoxy.

Proposed list of epoxies to seal the tie hole plug:


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BURKE NS normal set Class “B”, Grade 3, Type IISIKADUR 31 SBA,SIKADUR 31 Hi-Mod Gel (for repair only),CAPPAR Capbond EX

NOTES:

1. Refer to Appendix a for the correct repair materials for size of repair and repair orientation (horizontal, vertical, formed etc.).

2. Refer to Appendix 3 for temperature requirements.3. Refer to manufacturers data sheets for correct

material and placing methods.

Mix and apply the epoxy in strict accordance with manufacturer’s recommendations.

The outer edge of the concrete plug should be flush with the outside surface. A 5 mm projection or inset is acceptable.

For exposed tie holes, use an epoxy with colour similar to concrete. Leave only a visible bead of epoxy around the circumference of the plug.

5.4.2.5.2 Tie Holes in the Top Deck

NOTES:

1. Follow the procedure for application of tie hole plugs.

2. Plug required on topside only, provided that the inside surface of the tie hole may be coated with Caprock EX Clear.

3. Where possible, plug both sides of the tie hole

Preparation: After the plastic sleeve is removed, the surface of the tie hole is to be roughened by reamer or sandblast.

Proposed Repair Material:

1. Drypacked, as noted in Section 5.4.2.5.3 of this document

2. Filled with a flowable mix, as noted in Section 5.4.2.5.4 of this document.


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NOTES:1. Refer to Appendix 1 for the correct repair materials

for size of repair and repair orientation (horizontal, vertical, formed etc.).



5.4.2.5.3 Tapered Tie Holes

The holes may be plugged by the same period method as in the previous Section. Appendix 6, or, dry-packed with acceptable repair materials listed below.


1. EMACO S88-CA,2. EMACO T415, or,3. EMACO T430

NOTES:

1. Refer to Appendix 1 for the correct repair materials for size of repair and repair orientation (horizontal, vertical, formed, etc.).



Surface Preparation: Outer surface of hole to be roughened by reamer or sandblast. Surfaces are to be cleaned and wet or damp prior to application with no standing water. Surfaces must be free of laitance, dirt, and debris prior to application.


Proposed Curing Compound: SEALTIGHT CS-309 (the application rate of the product is 4 m² per litre, applied by spray or roller paint methods after initial set of the repair material).


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5.4.2.5.4 Embedded Bolts

For repair of holes after bolts are removed.

Proposed Repair Materials:1. EMACO S88-CA2. EMACO S77-CR3. EMACO T4154. EMACO T430

NOTES:1. Refer to Appendix 1 for the correct repair materials for size of the repair and repair orientation (horizontal, vertical, formed, etc.)2. Refer to Appendix 3 for temperature requirements.3. Refer to manufacturers data sheets for correct material and placing methods.

Surface Preparation: Outer surfaces of hole to be roughened by reamer or sandblast. Surfaces are to be clean and wet or damp prior to application with no standing water. Surfaces must be free of laitance, dirt and debris, prior to application.


Proposed curing compound: (SEALTIGHT CS-309) (the application rate of the product is 4m2 per litre, applied by spray or roller paint methods after initial set of the repair material).

5.4.2.5.5 Core Holes


1. EMACO S66-CR up to 100 mm depth and diameter,2. EMACO S88-CA extended for cores 50 to 200 mm

diameter and 200 mm deep.

NOTES:

1. Refer to Appendix 1 for the correct repair materials for size of repair and repair orientation (horizontal, vertical, formed etc.).


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materials and placing methods.

When core holes (horizontal or vertical) are made on the match-cast face between two precast elements, the exposed face of the repair material is to be recessed at least 3 mm from the match-cast face. During erection, these recesses will be filled with the segment epoxy-bonding agent.

Curing: Two coats of curing compound should be applied in complete or as soon as the surface cannot be marred by the application.


5.4.2.5.6 Miscellaneous Embedded Items

Surface Preparation: Chip the concrete up to the depth of the specified cover all around the embedded bolt or piece of metal that has to be removed.

The size of the chipped area should allow the operator to remove any embedded item up to the depth of the specified cover by means of wrench, tool or cutting torch without damaging or burning the concrete. Remove damaged concrete.


1. EMACO S77-CR (no bond slurry required),2. EMACO S88-CA (bond slurry required),3. EMACO T415 (bond slurry required),4. EMACO T430 (bond slurry required),5. EMACO T415 extended with stone (bond slurry

required),6. EMACO T430 extended with stone (bond slurry

required),7. EMACO R300 (bond slurry required),8. EMACO S66-CR (bond slurry required), or,

NOTES:


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1. Refer to Appendix 1 for the correct repair materials for size of repair and repair orientation (horizontal, vertical, formed etc.),






5.4.2.5.7 Drain Holes and Ventilation Holes in Bottom Slab

Drain and vent holes are left unplugged. The plastic sleeve is left in the hole and the top edge of the sleeve is sealed with Sikadur 52 Injection Resin, applied by gravity feed method.

5.4.2.6 Post Tensioning Anchorheads, Recesses, P.T.Blockouts and Grout Vents

5.4.2.6.1 Definition

Anchorhead Recesses: Local recesses around the anchorheads.

P.T.blockouts: Blockouts provide access to the anchorheads for stressing operations. Blockouts are larger than recesses and may contain one or more anchorheads.

5.4.2.6.2 Anchorages


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Anchorhead & Base Plate Surface Preparation:

To prevent rusting (prior to stressing and infilling recesses): coat anchor plates and bearing plates with a film of zinc enriched product.

Proposed Zinc Coatings:

ZRC Cold Galvanizing Compound and Carbo Zinc 11.

Clean metal surfaces with a steel wire brush or other appropriate method to remove all scaling and loose rust.Surface completely dry, clean, and free of dust.

Proposed Epoxies for Sealing:

SIKADUR 31 or SIKADUR 32

Other coating product:

DENSO PASTE

NOTE: If practical, epoxies should be tacky at the time the recess is filled with repair material.

After stressing and/or grouting, seal all anchorage hardware including anchorhead wedges and strand with accepted epoxy or alternatively to prevent rusting, apply a generous continuous coating of an accepted zinc rich primer.

Rusting of anchorages is to be avoided, as rust will interfere with epoxy bonding. Where rusting has not been prevented, and steel cannot practically be cleaned to white-metal finish, a zinc coating may be used in lieu of epoxy. Clean metal surfaces with a steel wire brush or other appropriate method to remove all scaling and loose rust. Clean surface completely dry and free of dust. Normally, a clean metal surface is required for zinc coatings but in this particular application tight rust is considered acceptable, as the coating will act as a sacrificial anode even if it is not in direct contact with metal in all areas. There is a possibility that the zinc coating may not bond to the metal. Therefore, a non-shrink product is required to infill, or where not infilled, sealed with epoxy. This method may require future additional monitoring and maintenance.


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To protect the strand, seal the wedges and strand with epoxy or alternatively apply a generous continuous coating of zinc primer as previously noted.

Where permanent plastic grout caps are used and do not completely protect the anchorage, the exposed steel and edges around the caps are to be sealed with an accepted epoxy or alternative coat with Denso Paste. The latter is only acceptable where the metal will be left visible, and thus can be monitored for corrosion.

All products are to be used in accordance with the manufacturer’s recommendations for surface preparation, cleaning, mixing and application, with exception to cleaning for zinc coatings, as previously noted. Epoxy requires clean surfaces by sandblasting or equivalent methods to ensure a good bond.

On horizontal surfaces, it is intended that the epoxy be gravity-fed into any cracks or voids that may exist. Therefore, depending on the uptake at the specific location, sufficient material needs to be poured on the deck surface to accomplish this.

5.4.2.6.3 Grout Vents Made of Steel Pipe

Used for the connection Pier Base/Pier Shaft and sealed as follows:

Preparation: The recess that has been left all around the thread of the pipe during the prefabrication is to be free of all laitance, dirt, dust, oil or other debris. The nipple, the pipe extension and the valve used during the grouting are to be removed when the grout has reached the required strength.

Proposed Repair Material for Coating: The recess and the part of the steel grout vent protruding in the bottom of the recess are to be thoroughly coated with SIKADUR 32.

Proposed Repair Material to Fill Recess: Before the epoxy resin has hardened, the hole is to be repaired with EMACO S88-CA.

NOTES:1. Refer to Appendix 1 for the correct repair

materials for size of repair and repair orientation (horizontal, vertical, formed etc.).


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2. Refer to Appendix 3 for temperature requirements.

3. Refer to manufacturers data sheets for correct material and placing methods.


Proposed Curing Compound: SEALTIGHT CS-309 (the application rate of the product is 4M² per litre, applied by spray or roller paint methods after initial set of the repair material).

5.4.2.7 Manholes/Access Holes

Surface Preparation: The area around the manhole cover should be thoroughly cleaned to remove all laitance, grease, oil, curing compound or other debris.

The substrate concrete is to be wet or damp prior to the repair material, with no standing water.


1. EMACO T415 (bond slurry required)2. EMACO 430 (bond slurry required)3. EMACO S77-CR, extended with stone (no bond

slurry required) or,4. SET 45 (no bond slurry required).

NOTES: 1. Refer to Appendix 1 for the correct repair materials

for size of repair and repair orientation (horizontal, vertical, formed, etc.).





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5.4.3 Structural Defects: Honeycomb, Voids, Cavities and Spalls

Surface Preparation: Edges are to be squared and roughened to a minimum depth of 10 mm, all around the damaged area.Square steps may be used in compression zones provided steps are at least 50 mm deep.

Do not cut or damage the reinforcing with chipping equipment. Remove all unsound concrete by light chipping hammer or chisel bit to 30 mm behind the reinforcing. Do not use equipment or methods that could fracture the concrete or aggregates. Do not use a bush hammer.

Prepare defect surfaces to exposed sound aggregate and roughen the concrete surface to minimum amplitude of 5 mm.

The substrate is to be free of all laitance, curing compound, dirt, dust, oil or other debris. Power water wash is recommended.

The surfaces are to be wet or damp prior to application with no standing water.

Mix and apply the repair material in strict accordance with manufacturer’s specifications. Do not exceed the recommended water/cement ratio.

Reinforcing may be added as directed by the Engineer.


1. EMACO S77-CR (no bond slurry required),2. EMACO S77-CR extended with stone (no bond

slurry required),


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3. EMACO S88-CA (bond slurry required),4. EMACO S88-CA extended with stone (bond slurry

required)5. EMACO T415 (bond slurry as per manufacturer’s

recommendations),6. EMACO T430 (bond slurry as per manufacturer’s

recommendations),7. EMACO T415 extended with stone (bond slurry

required)8. EMACO T430 extended with stone (bond slurry

required)9. EMACO R300 (bond slurry required)10. EMACO S66-CR (bond slurry required), or,

NOTES:1. Refer to Appendix 1 for the correct repair materials

for size of repairs and repair orientation (horizontal, vertical, formed, etc.)




Note that EMACO S66-CR is acceptable with saturation only, without a scrub coat for formed and pumped applications as long as sufficient pump pressure and proper consolidation are possible.

Overhead Repairs:EMACO S88-CA is to be applied by lifts of no more than 25 to 38 mm.

Do not allow the product to dry out between two lifts.

Finish with a wet trowel to match the existing concrete finish. For vertical repair, provide formwork constructed with the “bird-mouth” technique and tighten to the concrete surfaces.

After stripping the form, the “bird-mouth” is to be chipped off and smoothened.


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5.5 Inspections and Test Plans

All segments are to be inspected by the QC engineer immediately following stripping of the form. All deficiencies are to be recorded on the Post-pour inspection sheet IF48 (see WM#50 for copy of this sheet).

In the case QA and/or a structural defect being reported by the QC Engineer, the SAR Transit Design Department will immediately inform the Engineer and will send a copy of the Inspection Form.

6.0 REFERENCES

Acceptance Criteria for Concrete Repair Materials

1.1.1.Rapid Chloride Permeability

Standard: AASHTO T227/AASHTO C1202Criteria: Less than 1000 Coulombs in 28 days

1.1.2 Chloride Levels

Chloride based materials are not to be used. Chloride levels are not to exceed those contained in mixing water which must meet the standards for drinking water.

1.1.3 Drying Shrinkage

Criteria: Zero percent at 28 days.

1.1.4 Compressive Strength

Standard: ASTM C109Criteria: To be comparable to specified strength of sustrate concrete. Note: 50 mm cubes overestimate cylinder strength by 15 to 25 percent.

1.1.5 Flexural Strength

Standard: ASTM C348Criteria: To be comparable to specified strength of substrate concrete.


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1.1.6 Bond Strength and Tensile Strength

Standard: Determined by the 60 degree shear test.CSA 23.2 – 6BCriteria: Tensile bond strength of repair materials to substrate not to be less than 2 Mpa at 28 days.

1.1.7 Splitting Tensile Strength


1.1.8 Modulus of Elasticity


7.0 ATTACHMENTS

7.1 Appendix 1 Selection of Products and Type of Repair7.2 Appendix 2 Proposed Bug Holes Classification7.3 Appendix 3 Repair Material Application Temperatures7.4 Appendix 4 Crack Dimensions and Treatment

Originated: ______________________ //______________ // Rob Boyce Date Reviewed JMI Date

Reviewed: ________________________//_____________ // Quality Assurance Manager Date Reviewed Design Dept. Date
