403.01 284 SECTION 403 – TACK COAT
403.01 Des cription ................................ ................................ ................... 284
403.02 Bituminous Materials ................................ ................................ ... 284
403.03 Equipment ................................ ................................ .................... 285
403.04 Preparing the Surface ................................ ................................ ... 285
403.05 Applying Emulsified Asphalt ................................ ....................... 285
403.06 Method of Measurement ................................ .............................. 287
403.07 Basis of Payment ................................ ................................ .......... 287
DESCRIPTION
403.01 Description
This work consists of furnishing and applying emulsified asphalt to a previously prepared base or surface course to provide bond for a superimposed course. MATERIALS
403.02 Bituminous Materials
Provide materials as specified in: Emulsified Asphalt, SS -1, SS-1h, CSS-1, CSS-1h, TST-1P, CQS-1h, CQS-1hp, RS-1, CRS-1…………………………. 904.03 Approved Trackless Tac k………………………………………... QPL Apply tack coat at the temperature ranges specified in Table 403.02 -1. 403.03 285 Table 403.02-1: Tack Coat Application Temperatures Material Temperature Range SS-1, SS-1h, CSS-1, TST-1P, CQS-1h, CQS-1hp, and CSS-1h 70 to 160 F Approved Trackless Tack from the QPL Per Manufacturer’s Recommendation Dilution of asphalt emulsion used for tack coat on hot mix asphalt paving projects after leaving the terminal is not allowed. Apply the emulsion as delivered from the terminal. EQUIPMENT
403.03 Equipment
Provide a power broom, equipment for heating bituminous material, a pressure distributor meeting the requirements of 402.03, and such other equipment and small tools as may be required to perform the work in a satisfactory manner.
403.04 Preparing the Surface
Prepare the designated surface as specified in 404.05. Ensure that the surface is dry when applying tack coat.
403.05 Applying Emulsified Asphalt
A.Emulsified Asphalt Immediately after cleaning the sur face, apply emulsified asphalt with the pressure distributor at a rate, established by the Engineer, within the range of 0.05 to 0.10 gallons per square yard of applied emulsion. If the bituminous material is to be placed upon a milled surface, apply at a rate, established by the Engineer, within the range of 0.08 to 0.12 gallons per square yard of applied emulsion. When applying tack coat on freshly - placed asphalt, lower application rates may be permitted, provided a full coverage application is still ac hieved. For slurry seal and microsurface, apply a tack coat of SS -1h, CQS-1h, or CQS-1hp emulsion. The tack coat shall consist of one part emulsion and three parts water. The application rate shall be 0.10 to 0.15 gallons per 403.05 286 square yard of the diluted e mulsion. The Engineer will determine the actual application rate. Protect the surfaces of trees and structures adjacent to the area being treated to prevent their being splattered or marred. Allow the emulsified asphalt to break prior to paving the next course. Apply tack coat only so far in advance of the paving operations as is necessary to obtain this proper condition of tackiness. Protect the tack coat from damage until the next course is placed.
B.Test Strip When setting up an initial roller pattern and density test strip for the first layer of asphalt mixture, prepare a tack coat test strip to demonstrate that the proposed equipment and methods will achieve proper application of tack coat. For the test strip, apply the tack material at a rate of b etween 0.05 and 0.10 gallons of applied emulsion per square yard. If placing the bituminous material upon a milled surface, apply the tack material at a rate of between 0.08 and 0.12 gallons applied emulsion per square yard. In all cases, ensure that the application will result in a minimum double overlap of the actual tack spray as it lands on the surface. Adjustment of the spray-bar and the nozzles may be necessary to achieve this minimum double overlap. Corn -rows or any o ther pattern that would result in less than double overlap coverage of the tack coat is not acceptable for the tack application. The goal is to have a very thin but uniform coating of asphalt left on the surface when the emulsion has broken. Once the te st strip has been demonstrated and approved by the Engineer, use the same procedure and application rates for the entire project or until another design is proposed and accepted.
C.Fog Sealing When the Contract requires bituminous materi al for fog sealing of shoulders, provide emulsified asphalt meeting 403.02 or an item from QPL 40A . Apply diluted emulsified asphalt at a rate of 0.10 to 0.15 gallons per square yard based on a dilution rate of one part emulsified asphalt to one part water. This application may require two equal increments if run -off occurs. 403.06 287 COMPENSATION
403.06 Method of Measurement
The Department will measure Emulsified Asphalt for Tack Coat and Fog Sealing by the ton, as delivered from the terminal, in accordance with 109. The Department will make no direct payment for water used to dilute Emulsified Asphalt for Fog Sealing.
403.07 Basis of Payment
The Department wil l pay for accepted quantities, complete in place, at the contract prices as follows: Item Pay Unit Emulsified Asphalt for Tack Coat Ton Emulsified Asphalt for Fog Seal Ton The Department will measure and pay for the work required to prepare the designated surface, as provided for under 403.04, in accordance with the applicable Section or Subsection under which the work is performed. 405.01 288 SECTION 405 – BITUMINOUS SEAL COAT
405.01 Description ................................ ................................ ................... 288
405.02 Materials ................................ ................................ ...................... 288
405.03 Equipment ................................ ................................ .................... 289
405.04 Limita tions ................................ ................................ ................... 289
405.05 Preparing the Designated Surface ................................ ................ 289
405.06 Application ................................ ................................ ................... 290
405.07 Spreading and Rolling Aggregate ................................ ................ 293
405.08 Shoulders ................................ ................................ ...................... 294
405.09 Maintenance and Protection ................................ ......................... 294
405.10 Method of Measurement ................................ .............................. 295
405.11 Basis of Payment ................................ ................................ .......... 295
DESCRIPTION
405.01 Description
This work consists of constructing a bituminous seal coat consisting of one or more applications each of bituminous material and cover aggregate. MATERIALS
405.02 Materials
Provide materials as specified in: Mineral Aggregate, Size No s. 7, 8, 78, 89 ............................. 903.13 Mineral Aggregate ................................ ................................ . 903.14 Emulsified Asphalt, CRS -2p ................................ .................. 904.03 Apply seal coat at a temperature range of 60 to 140 F.
Source: Tennessee Standard Specifications for Road and Bridge Construction, 2021 Edition. Pages 293–296 of 1,072.