High Friction Surface Treatment for High Crash Locations

Project status

In progress

Start date: 07/01/14
End date: 09/30/19


Principal investigators:

Co-principal investigators:

About the research

Horizontal curves are over-represented, high-frequency, high-severity crash locations. A relatively new and innovative, yet somewhat more costly, horizontal curve crash mitigation strategy is high friction surface treatment (HFST). The Iowa Department of Transportation (DOT) currently has an initiative to begin trial implementation of HFST on horizontal curves throughout the state. However, no formal criteria for consideration of HFST application has been established. The objective of Phase 1 of this project is to develop a preliminary HFST candidate site selection criteria and apply this criteria to identify appropriate candidate high speed, primary and secondary paved horizontal curves for HFST application.

The primary focus of this research effort is utilization of disparate data sets to develop site selection criteria, and ultimately identify candidate sites, for HFST application to improve traffic safety. This will allow the Iowa DOT to allocate limited resources to locations with the most need, which addresses the MTC theme of optimized decision making.

The Phase 2 effort focuses on evaluation of HFST as a mitigation strategy, which directly relates to the MTC theme of data-driven performance measures for safety. The results of this project may establish a framework for determining which horizontal curves may be the best candidates for HFST, given the many other possible mitigation strategies available.

Future analyses may be used to further assess or refine these criterion. Highway agencies may then more confidently utilize HFST in their safety arsenal, which addresses the MTC focus area of technology transfer.



  • Iowa Department of Transportation
  • Midwest Transportation Center