01683220

Monograph

http://www.trb.org/main/blurbs/177925.aspx

This report presents the results of a comprehensive field validation of AASHTO TP 114: “Standard Method of Test for Determining the Interlayer Shear Strength (ISS) of Asphalt Pavement Layers.” The objective was to evaluate and to validate test method AASHTO TP 114 by correlating measured tack coat parameters with asphalt pavement performance at field projects constructed across the United States to support its implementation. The 10 projects included 33 in-service test sections for the evaluation of the effects of tack coat material type, pavement surface type, residual application rate, and time in service on the ISS. Further, an interface shear strength predictive model was developed for use by practitioners during the planning of overlay construction activities, selection of tack coat material type, and calculation of application rate, given the project conditions. The research demonstrated that the ISS values measured with test method AASHTO TP 114 correlated well with short-term cracking performance of the field pavements and verified that a minimum ISS of 40 psi was required for satisfactory tack coat performance. The research also established the effects of tack coat material type, pavement surface type, residual application rate, and time in service on ISS development. The practical outcome of the project is the validation of the utility of test method AASHTO TP 114 along with its threshold value of 40 psi to assess the effectiveness of tack coats to bond asphalt pavement layers to underlying asphalt or portland cement concrete surfaces. This report fully documents the research and includes three appendices presenting (1) the field project checklist, (2) photos of existing pavement distress at the Oklahoma and Louisiana field projects, and (3) a summary of test data from the field projects.

Project 09-40A

English

72p

2018

NCHRP Research Report

9780309446860

Print

Appendices; Figures; Photos; References; Tables

Asphalt pavements; Field tests; Pavement interlayers; Shear strength; Tack coats; Test procedures

Construction; Highways; Materials; Pavements

TRIS, TRB, ATRI

Oct 15 2018 8:16AM