Research Reports |
Title: | Development of a Guideline for the Selection of Tack Coats in South Dakota |
Authors: | Rouzbeh Ghabchi and Chamika Prashan Dharmarathna |
University: | South Dakota State University |
Publication Date: | Jul 2022 |
Report #: | MPC-22-468 |
Project #: | MPC-522 |
TRID #: | 01855174 |
Keywords: | freeze thaw durability, guidelines, shear strength, tack coats |
Type: | Research Report – MPC Publications |
Several types of tack coats are used in South Dakota for asphalt pavement construction projects. This study was conducted to determine the effects of application rate, surface type, texture, moisture, and freeze-thaw on the early-age performance of three tack coat emulsions applied on four surface types in dry conditions and after moisture-conditioning. The specimens' early-age interlayer shear strength (ISS) was measured and used to study the effectiveness of different tack coat types applied at different rates on each surface texture type. The effects of freeze-thaw cycles on the ISS values were examined on moisture-conditioned specimens. It was found that the samples prepared using tack coats having a harder binder grade exhibited higher early-age ISS values at low application rates compared with those prepared using a polymer-modified tack coat. In addition, it was found that applying tack coats resulted in a reduction in early-age ISS values for specimens prepared by using different textures of HMA surfaces. Moisture conditioning resulted in a considerable reduction in the specimens' ISS values consisting of an HMA layer compacted on a grooved PCC layer using different tack coats. The polymer-modified tack coat was the most effective in reducing moisture's effect on the ISS values.
Ghabchi, Rouzbeh, and Chamika Prashan Dharmarathna. Development of a Guideline for the Selection of Tack Coats in South Dakota, MPC-22-468. North Dakota State University - Upper Great Plains Transportation Institute, Fargo: Mountain-Plains Consortium, 2022.