02558 Tack Coat.doc

Base Pavements IDIQ

JCGU 09-1700

DIVISION 02 - SITE WORK

SECTION 02558 - BITUMINOUS TACK COAT

PART 1 – GENERAL:

1.1 REFERENCES:

The publications listed below form a part of this specification to the extent referenced. The publications are referred to in the text by basic designation only. All publications shall be the latest revision in effect on the date of solicitation except where a date is given.

American Society for Testing and Materials (ASTM), Publications:

ASTM D 140

Sampling Bituminous Materials

ASTM D 1250

Petroleum Measurement Tables

ASTM D 2995

Determining Application Rate of Bituminous Distributors

Standard Specifications for Construction and Maintenance of Highways, Streets, and Bridges, Texas Department of Transportation, June 2004.

1.2 SUBMITTALS:

The following shall be submitted in accordance with Specification SECTION 01010:

Test Reports:

Copies of all test results shall be furnished to the Contracting Officer within 24 hours of completion of tests.

Records:

The Contractor shall not remove bituminous material from storage until the initial outage and temperature measurements have been taken. The delivery or storage units shall not be released until the final outage has been taken. Copies of waybills and delivery tickets shall be submitted during the progress of the work. Before the final statement is allowed, the Contractor shall file with the Contracting Officer certified delivery tickets for all bituminous material used in construction of the pavement covered by this section of the specifications.

Waybills and delivery tickets shall be submitted during the progress of the work. Before the final statement is allowed, the Contractor shall file with the Contracting Officer certified waybills or certified delivery tickets for all bituminous material used in the construction of the pavement covered by contract.

1.3 WEATHER LIMITATIONS:

The tack coat shall be applied only when the surface to be treated is dry. The tack coat shall be applied only when the atmospheric temperature in the shade is 50 degrees Fahrenheit or above and when the temperature has not been below 35 degrees Fahrenheit for the 12 hours prior to application.

PART 2 – PRODUCTS:

2.1 Asphaltic material shall be emulsified asphalt grades cutback asphalt grade MC -30 or equal, conforming to TXDOT Standard Specification, Item 300, "Asphalts, Oils, and Emulsion", except that the measurement and payment paragraphs shall not apply. Bituminous materials delivered to the job site shall come from a source approved for use by the TXDOT. The seal number from the tank and the number of the TXDOT laboratory test report shall accompany each shipment. Certification is required for compliance.

PART 3 – EXECUTION:

3.1 PREPARATION OF SURFACE:

Immediately before applying tack coat, all loose material such as dirt, clay, or other objectionable material shall be removed from the surface to be treated, using a power broom or blower supplemented with hand brooms. After the cleaning operations and prior to the application of the tack coat, an inspection of the area to be treated shall be made by the Contracting Officer or his designated representative to determine the fitness of the area to receive the bituminous coating.

3.2 APPLICATION RATE:

Bituminous material for the tack coat shall be applied in quantities of not less than 0.05 gallons nor more than 0.15 gallons per square yard of pavement surface. The exact quantities within the range specified, which may be varied to suit field conditions, will be determined by the Contracting Officer or his designated representative.

3.3 APPLICATION TEMPERATURE:

Asphalt application temperature shall be within the following ranges except that appropriate changes shall be made when the range of viscosity is raised or lowered.

SS-1, MS-1

70-160 degrees Fahrenheit

MC-30

06-120 degrees Fahrenheit

3.4 APPLICATION:

The bituminous material shall be applied at a pressure within the range of 25 to 75 psi in the amounts specified. The bituminous material shall be applied with uniform distribution at all points of the surface to be treated. Unless the distributor is equipped to obtain satisfactory results at the juncture of previous and subsequent applications, building paper shall be spread on the surface for a sufficient distance back from the ends of each application so that the flow from the sprays may be started and stopped on the paper and so that all sprayers shall operate at full force on the surface to be treated. Immediately after the application, the building paper shall be removed and destroyed. All lightly coated areas missed by the distributor shall be properly treated with bituminous material. Following the application of bituminous material, the surface shall be allowed to dry until it is in a proper condition of tackiness to receive the surface course. The tack coat shall be applied only so far in advance of surface course placement as is necessary to obtain the proper condition of tackiness as determined by the Contracting Officer or his representative. The Contractor shall furnish and spread a sufficient quantity of clean, dry sand on all areas that show an excess of bituminous material, to effectively blot up and cure any excess, when directed by the Contracting Officer. The treated surface shall be maintained by the Contractor until the succeeding layer of pavement has been placed. During this interval the Contractor shall protect the treated surface against damage and shall repair all damaged spots at no additional cost to the Government.

3.5 FIELD QUALITY CONTROL:

Samples of the bituminous material shall be tested for compliance with the applicable specified requirements. A sample shall obtained and tested by the Contractor for every 100 gallons of bituminous material used.

3.6 SAMPLING AND TESTING:

3.6.1 General Requirements: Sampling and testing shall be performed by an approved commercial testing laboratory or by facilities furnished by the Contractor. No work requiring testing shall be permitted until the facilities have been inspected and approved.

3.6.2 Sampling: The samples of bituminous material, unless otherwise specified, shall be in accordance with ASTM D140.

3.6.3 Initial Sampling and Testing

3.6.3.1 Bituminous Materials: Sources from which bituminous materials are to be obtained shall be selected and notification thereof furnished the Contracting Officer within 15 days after the award of the contract. Certified copies of the manufacturer's test reports indicating compliance with applicable specified requirements shall be submitted to the Contracting Officer not less than 15 days before the material is required in the work.

3.6.3.2 Calibration Test: The Contractor shall furnish all equipment, materials, and labor necessary to calibrate the bituminous distributor. Calibration shall be made with the approved job material and prior to applying the tack coat material to the prepared surface. Calibration of the bituminous distributor shall be in accordance with ASTM D2995.

3.6.3.3 Trial Applications: As a preliminary to providing the complete tack coat, three lengths of at least 100 feet for the full width of the distributor bar shall be tacked to evaluate the amount of tack that can be satisfactorily applied. Unless otherwise authorized, the trial application rate of bituminous materials shall be applied in the amount of 0.05 gallons per square yard. Other trial applications shall be made using various amounts of material as may be deemed necessary.

3.6.4 Sampling and Testing During Construction: Quality control sampling and testing shall be performed as required in paragraph 3.5 - "Field Quality Control."

END OF SECTION

Section 02558 - Page 4 of 4