FRT 234: How Pavement Macro-Texturing Affects Friction and Create/Verify Testing Procedures for the Three-Wheel Polishing Device and the Dynamic Friction Tester (Phase 1)

Abstract FRT 234, How Pavement Macro-Texturing Affects Friction and Create/Verify Testing Procedures for the Three-Wheel Polishing Device and the Dynamic Friction Tester (Phase 1) 01/01/2022-12/31/2024 Principal Investigator: Clark Graves Co-I''s: Brad Rister, Kean Ashurst, David Hacker Providing safe roads for traveling public is a primary concern for the Kentucky Transportation Cabinet (KYTC) and they are always striving to reduce crashes and limit fatalities on Kentucky’s roadways. One method to reduce crashes is to improve the friction between a vehicle’s tire and the pavement surface. In an effort to reduce crashes, KYTC is looking for new methods to optimize friction through aggregate selection, aggregate gradation, mixture design, and understanding the short- and long-term effects to the macro-texture of the pavement wearing surface has over time. The challenge is the state of Kentucky has a limited types of polish resistant aggregate and their respective sources. So, proposed methods would need to maximize the use of local aggregate sources. In addition to developing improved methods to enhance the performance of existing materials there is a need to understand how the macro-texture of the wearing surface changes over time to estimate the approximate loss of friction at the end of a pavements expected life. The objective of the research is to improve long term friction for Kentucky’s pavements and provide a design tool that will help estimate the friction of a pavement near the end of its design life. In order to accomplish the research objective, the following will need to be accomplished: • Understanding how mixture design, aggregate type, and changes to macro-texture over time affects friction. • Establish correlation between KY accident rates and friction • Obtain mix designs and friction measurement correlations from NCAT. • Develop method for testing friction in the laboratory. • Develop and design tool to estimate friction of pavement at the end of its design life