Field performance evaluation of high friction surface treatments (HFST) in Oklahoma

Abstract

The high friction surface treatment (HFST) is an effective countermeasure to roadway departure crashes. The field performance of the HFST system was evaluated from seven field monitoring trials on six HFST sites in Oklahoma from 2015 to 2017. HFST sections have statistically significant higher pavement friction and macrotexture in contrast to the adjacent untreated pavements. Meanwhile, distresses including patching, reflective cracking, raveling, and delamination have been observed on these HFST sites. The number of property damage crashes and injured crashes before and after the HFST installation are queried from the Oklahoma safety database. The HFST results in 29% to 100% reductions of annual property damage crashes and 100% reduction of annual injured crashes. The benefit-cost ratios of the HFST sites range from 6.9 to 27.9. In addition, HFST sites constructed with bauxite show higher friction numbers and better polishing resistance performance than sites using the local mine chat aggregates.