|Project Name:||Pavement Friction Thresholds|
Office of Infrastructure Research and Development |
|Team:||Infrastructure Analysis and Construction Team|
Infrastructure Research and Technology Strategic Plan and Roadmap|
Comprehensive Approach to Safety
|Project Description:||In phase I, the contractor performed a literature review on pavement friction and macro-texture and safety. They wrote a report on theoretical vehicle, tire, and pavement interactions as they relate to skid crashes in order to recommend the best equipment to measure friction and macrotexture. In phase II, the contractor will use the recommended equipment (purchased by Federal Highway Administration) in four States to test about 700 sites to develop Pavement Friction Thresholds and Management Programs.|
|Start Date:||November 22, 2010|
|End Date:||August 28, 2016|
The key project objectives are:
(1) Perform tests and analyses to determine criteria, and develop methods to establish investigatory (desirable) and intervention (minimum) levels for friction and macrotexture, for selected State Department of Transportation (DOT) agencies.
(2) Assist four State DOTs to develop "Pavement Friction Management Programs."
(3) Demonstrate state-of-the-art friction measurement equipment.
|Test Methodology:||We got stakeholder input for the recommended continuous friction measurement equipment, i.e. aSideways Coefficient Routine Investigation Machine (SCRIM), procure a machine, and use it in field tests to predict crash histories.|
|Fieldtest:||The contractor will test the friction and macrotexture of a variety of pavement types, to develop and demonstrate thresholds values as part of Pavement Friction Management Program.|
|Expected Benefits:||States have found benefit-cost ratios of up to 15, based on crash reductions.|
|Project Findings:||Three pieces of continuous pavement friction measurement equipment were identified, for possible use in phase II, i.e. the Dynatest Highway Friction Tester, the ROADSTAR, and the Sideways Coefficient Routine Investigatory Machine (SCRIM) at a 34% fixed slip ratio. The ROADSTAR and the Dynatest equipment use the linear friction coefficient principle which relates more to braking versus turning friction..|