atch 1 2572 Re-Sealing.pdf

Re-Sealing Existing Concrete Joints and Cracks FA5000-12-R-0001 Attachment 1

2572- 1

SCOPE:

1.1 This section covers cleaning, surface preparation, and resealing of joints and cracks in existing Portland Cement concrete pavement.

2. APPLICATION STANDARDS:

Federal Specifications (Fed. Spec.)

3. MATERIALS:

3.1 Sealant Type and Usage:

3.1.1 Type IV sealant

: Type IV sealant shall conform to Fed. Spec. SS-S-200, Type M or Fed Spec.

SS-S-1614, Type I, Class 2. The sealant shall be of a basic composition that has had documented satisfactory field performance for a period of not less than two years.

3.2 Primers

: The use of primers when recommended by the manufacturer of the proposed sealant is authorized in accordance with the manufacturer's instructions.

3.3 Sampling and Testing: Joint sealants will be tested for conformance with the referenced applicable material specification. The Contracting Officer or designated representative shall be notified in writing of the proposed sources of joint sealants at least 30 days prior to the date the materials will be required at the project site. Joint sealants will be sampled at the place of manufacture, tested by the Contractor, and test reports and samples provided to the Contracting Officer for approval.

3.3.1 No material shall be used in the project prior to receipt by the Contractor of written notice that the material meets the laboratory test requirements. If the use of a primer is recommended for the proposed sealing system, the laboratory test for bond will be conducted using the primer in accordance with the manufacturer's instruction.

3.3.2 The cost of the tests of samples from each lot of joint sealant will be borne by the Contractor.

SS-S-200E Sealing Compounds, Two-Component, Elastomeric, Polymer Type, Jet-Fueled Resistant, Cold-Applied

SS-S-1614A Sealing Compounds, One-Component, Jet-Fuel Resistant, Hot Applied.

Pavements - IDIQ

FXSB 11-2102

Section 2572

Re-Sealing Existing Concrete Joints & Cracks

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If the sample fails to meet specification requirements, the material represented by the sample shall be replaced, and the new material will be tested.

3.3.3 The cost of sampling and testing the new material will be paid by the Contractor.

Conformance with the requirements of the laboratory tests specified will not constitute final acceptance of the sealing material. Final acceptance will be based on performance of the in-place sealant.

3.4 Delivery and Storage of Materials: Materials delivered to the site shall be inspected for damage, unloaded, and stored with a minimum of handling. Materials shall be handled in such a manner as to ensure installation in the joint in the prescribed manner. Storage facilities shall be provided by the contractor at the job site for maintaining materials at temperatures recommended by the manufacturer.

4. EQUIPMENT:

4.1 All machines, tools, and equipment used in the performance of the work required by this section will be inspected and accepted by the Project engineer / project inspector before the work is started and shall be maintained in satisfactory condition at all times.

4.2 Joint Cleaning Equipment:

4.2.1 Cutting tools to be used for removing old sealant from the joints to the specified depth shall be of the hardened steel, vertical, single cutting edge type, and so fabricated that when mounted in a holding device the cutting edge shall be approximately parallel to the joint walls. The maximum thickness of the body of the cutting edge shall not exceed 50 percent of the width of the joint being cleaned. The device will be so constructed and adjusted within springs or hydraulic parts so that contact with any wedged foreign object, irregular joint wall surfaces, or nonalignment of joint at intersections will release pressure on the cutting device prior to causing concrete spalling along the joint edges. The use of V-shaped tools or rotary impact routing devices will not be permitted in joints.

4.2.2 Sandblasting Equipment: Sandblasting equipment shall include an air compressor, hose, and long-wearing, 1/4-inch, venturi-type nozzles of proper size, shape, and opening. The air compressor shall be portable and shall be capable of furnishing not less than 150 cfm and maintaining a line of pressure of not less than 90 psi at the nozzle while in use. Compressor capability under job conditions must be demonstrated before approval. Compressor shall be equipped with traps that will maintain the compressed air free of oil and water. The nozzle or nozzles shall have an adjustable guide that will hold the nozzles aligned with the joint about one inch above the pavement surface. The height, angle of inclination, and size of the nozzles shall be adjusted as necessary to secure satisfactory results.

4.2.3 Concrete Saw: A self-propelled power saw with diamond or abrasive saw blades shall be provided for cleaning joints and for removing filler embedded in the joints or adhering to the joint faces.

4.2.4 Sealing Equipment: The equipment for proportioning, mixing, and installing Type IV cold-applied joint sealant shall be designed for delivering two semi fluid components to a portable mixer through hoses at a preset ratio of one to one (by volume) by positive displacement with an accuracy of plus or minus five percent, for the quantity of each component. The reservoirs for each

2572- 3 component shall be equipped with mechanical agitation devices that will maintain the components in a uniform condition without entrapping air. Provisions shall be incorporated to permit thermostatically controlled indirect heating of the components when required; however immediately prior to proportioning and mixing, the temperature of either component shall not exceed 90 degrees F. Screens with square openings not exceeding 3/16-inch shall be provided near the top of each reservoir to eliminate any foreign particles or partially polymerized material that could clog fluid lines or otherwise cause misproportioning or improper mixing of the two components. The equipment shall be capable of intimately mixing the two components through a range of application rates of 10 to 60 gal/hr and through a range of pressures from 50 to 1,500 psi as required by material, climatic, or operating conditions. The mixer shall be designed for the easy removal of the supply lines for cleaning and for checking proportioning of components. The mixing head shall accommodate nozzles of different types and sizes as may be required by various operations. The dimensions of the nozzles shall be such that the nozzle tips will extend into the joint as necessary to fill the joint from the bottom to top of the joint. Before using the equipment in this work, the Contractor shall furnish the supplier's certification that the specific equipment model and serial number is recommended for use with the sealing compound to be installed. The initially approved equipment shall be maintained in good working condition, serviced in accordance with the supplier's instructions, and shall not be altered in any way, unless allowed otherwise by the Contracting Officer or designated representative.

4.2.5 Sealing Equipment: The melter unit for the FS SS-S-1614 material shall be of the double boiler type equipment with an aggeator and using high flash oil, 600 degrees F. minimum, as a heat transfer medium. The melter unit shall be equipped with a pump capable of circulating the material from the bottom to the top of the kettle. The sealing compound shall be agitated continuously during the melting and pouring process.

4.3 Crack Cleaning Equipment:

4.3.1 A Vertical rotary routing machine shall be used to widen and prepare random cracks for sealing operations. Operation of the router shall not cause spalling of the walls of the crack.

4.3.2 Sandblasting equipment shall be as specified in paragraph 4.1.2.

5. EXECUTION:

5.1 Delivery and Storage of Materials: Materials delivered to the site shall be inspected for damage, unloaded, and stored with a minimum of handling. Materials shall be handled in such a manner as to ensure installation in the joint in the prescribed manner. Storage facilities shall be provided by the Contractor at the job site for maintaining materials at temperatures recommended by the Manufacturer.

5.2 Preparation of Joints: The Contractor shall remove all in-place sealant, reface the joint faces, sandblast the joint faces, remove all deposited sandblasting sand & other foreign material including water, & shall place a separating medium. These operations shall be accomplished as follows:

5.2.1 Existing Sealant Removal: The in-place sealant shall be cut loose from each joint face independently, using the vertical cutting edge tool. After separately cutting free the existing sealant from both joint faces, the sealant shall be removed from both joint faces using a curved finger-type tool having a cutting leading edge and a width slightly less than the existing joint width. Removal of sealant shall be to the depth required to accommodate any separating and/or depth blocking

2572- 4 medium used and to maintain the specified depth for the new sealant to be installed. Prior to refacing of the joint surfaces, all loose old sealant remaining in the joint opening shall be completely removed.

5.2.2 Refacing to joints shall be accomplished using a power-driven concrete saw with diamond or abrasive blades to remove all residual old sealant and a minimum of concrete from the joint faces to provide exposure of newly clean sound concrete. Joints greater than 3/4-inch wide will be repaired as specified in Section 02575. A sufficient number of used or dummy blades shall be mounted on the same arbor as the cutting blade to assist in a straight-line sawing and to provide stiffness to avoid blade distortion. Immediately following the sawing operation, the joint faces and opening shall be thoroughly cleaned using a high-pressure water jet to remove all saw cuttings or debris remaining on the faces or in the joint opening.

5.2.3 Sandblasting Cleaning: The newly exposed concrete joint faces and the pavement surfaces extending from the range of about 1/2-inch from the joint edges shall be sandblast cleaned. A multiple-pass technique shall be used until the surfaces are free of any traces of old sealant and free of saw-cutting fines that might prevent bonding of the sealant to the concrete. A minimum of 150 cubic feet per minute of air at a nozzle pressure of 90 pounds per square inch shall be used for sandblasting and for final cleaning. After final cleaning and immediately prior to sealing, the joints shall be blown out with compressed air and left completely free of sand and water. Sand used for sandblasting shall be silica-free.

5.2.4 Separating and Blocking Media: When the joint groove or opening is of greater depth than indicated, the lower portion of the groove shall be plugged or sealed off to prevent entrance of the sealant below the depth specified. The material used to seal off the lower portion of the joint shall be a readily compressible, nonshrinke, nonreactive with the sealing compound, non-absorptive type such as butyl or neoprene foam rubber, and shall not be stretched or twisted during insertion in the joint. Submit material sample for approval by the Contracting Officer.

5.2.4.1 Installing Tape: When the existing sealant has been removed, if the bottom of the joint opening to be resealed is formed by previously installed sealant, a nonreactive adhesive-backed tape shall be inserted. The tape shall be 1/8-inch wider than the nominal width of the joint to prevent contact of the newly installed sealant with the existing sealant. Submit material sample to the Contracting Officer for approval.

5.2.5 Rate of Progress of Joint Preparation: The work for the removal of existing joint sealant, widening and/or deepening of joint openings, if required, and refacing of joint walls may proceed at the rate of progress determined necessary by the Contractor to complete this work on time. The final stages of joint preparation which include sandblasting of the joint faces, air pressure cleaning of joints, and placement of separating and/or blocking media, if required, shall be limited to only that lineal footage of joint that can be resealed during the same workday.

5.3 Preparation of Crack:

5.3.1 Cracks shall be prepared and repaired as follows:

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5.3.2 Sandblasting cleaning shall be as specified in Paragraph 5.2.3.

5.3.3 Blocking media shall be as specified in Paragraph 5.2.4.

5.3.4 Rate of progress of crack preparation shall follow Paragraph 5.2.5.

5.4 Preparation of Sealant: Type IV-M cold-applied sealant components and containers shall be inspected by the Contractor and the Project engineer / project inspector prior to use, and any materials that contain water, hard caking of any separated constituents, nonreversible jell, or are otherwise unsatisfactory shall be rejected. Settlement of constituents in a soft mass that can be readily and uniformly remixed in the field with simple tools shall not be caused for rejection. Prior to transfer of components from the shipping containers to the appropriate reservoirs of the application equipment, the materials in the shipping containers shall be thoroughly mixed to ensure homogeneity of the components and incorporation of all constituents at the time of transfer. When necessary for remixing prior to transfer to the application equipment reservoirs, the components of the sealant shall be warmed to a temperature not exceeding 90 degrees F by placing the components in heated storage or by other approved methods, but in no case shall the components be heated by direct flame, or in a single-walled, non-oiled bath kettle.

5.5 Installation of Sealant:

5.5.1 Area of Installation: Existing joints in the concrete slabs shall be resealed by the Contractor in the areas designated by the Project engineer / project inspector. The cracks shall be sealed or resealed by the Contractor in the areas designated by the Project engineer / project inspector.

CRACK DESCRIPTION REPAIR METHOD

Hairline to 1/8-inch wide Do not fill *No evidence of spalling.

Hairline to 1/8-inch wide Sandblast and fill *Evidence of spalling starting to appear.

1/8-inch to 3/8-inch wide Sandblast and fill *No spalling apparent.

1/8-inch to 3/8-inch wide Route crack, *Minor spalling.

Sandblast and fill

3/8-inch to 3/4-inch wide Route crack, *Minor or no spalling.

3/8-inch to 3/4-inch wide Route crack, repair *Major spalling.

3/4-inch wide Major spalling.

Rebuild crack as if it were a joint.

See Section 2575

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5.5.2 Time of Application: Joints and cracks shall be sealed when prepared as specified. The concrete walls of the joint shall be surface dry, and the atmospheric and pavement temperatures shall be above 50 degrees F at the time of application of the sealant. Open joints and cracks that cannot be sealed under the conditions specified herein shall be provided with an approved temporary seal to prevent infiltration of foreign particles. When rain interrupts sealing operations, joints and cracks shall be re-cleaned prior to installing sealants.

5.5.3 Sealing Joints: No joint sealant shall be installed until the cleaned joints and cracks have been inspected and accepted by the Project engineer / project inspector. Unless otherwise directed, the joints shall be completely filled from the bottom up using the equipment specified. Excess or spilled sealant shall be removed from the pavement by approved methods and discarded. Traffic shall not be permitted over newly sealed pavement until authorized by the Project engineer / project inspector.

5.5.3.1 In no case shall sealant be installed using gravity methods and pouring pots. If a primer is supplied by the manufacturer, it shall be applied evenly to the joint faces in accordance with the manufacturer's recommendation. Proportioning by the two-component application equipment shall be checked in the beginning of each day's operation and every 4 hours, to determine that the preset volume output for each component is being maintained. The material used for these checks may be returned to the proper component reservoir. The joints shall be checked frequently by the quality control person to ensure that the newly installed sealant is cured to a tack-free condition within three hours.

5.5.4 Final Acceptance: In-place sealant which is not completely bonded to the concrete surfaces of the joint walls, or develops cohesive failures within the sealant, or contains voids or entrapped air, or fails to set to a tack-free condition within 24 hours will be rejected. Sealant may be rejected at any time prior to final acceptance of the project. Sealant which is rejected shall be removed from the joint, properly disposed of, and replaced with new joint sealant in a manner satisfactory to the Contracting Officer or designated representative.

6. CONTRACTOR’S QUALITY CONTROL:

6.1 Follow the requirements of the Contractor’s Quality Control in Section 2570 para 10.

7. MATERIAL SUBMITTALS:

7.1 Follow the requirements of the Material Submittals in Sections 2570 para 9.

8. DISPOSAL OF REMOVED SEALANT:

8.1 Existing sealant removed shall be disposed of at the approved off-JBER disposal site.

9. UNIT OF MEASUREMENT AND PAYMENT: Per the Bid Schedule and Section 1020.

End of Section