Citation

Albuquerque FDB, Sicking DL, Stolle CS, Faller RK, Lechtenberg KA, Emerson E. J. Transp. Saf. Secur. 2017; 9(4): 403-418.

Copyright

(Copyright © 2017, Southeastern Transportation Center, and Beijing Jiaotong University, Publisher Informa - Taylor and Francis Group)

DOI

10.1080/19439962.2016.1237599

PMID

unavailable

Abstract

Guardrails have commonly been installed to prevent errant vehicles from impacting roadside hazards. However, guardrail impacts have contributed to numerous serious injuries and fatalities. Plus, guardrails are generally impacted more often because they are installed closer to the edge of travel way and are much longer than the shielded hazard itself. Thus, to reduce the frequency of guardrail crashes, an optimized length should be determined. The American Association of State Highway and Transportation Officials (AASHTO) Roadside Design Guide (RDG) has suggested guardrail runout lengths which are dependent on posted speed limit and traffic volumes. Crash data analyses and simulation using the recently-updated Roadside Safety Analysis Program (RSAPv3) was conducted to evaluate the guardrail length-of-need (LON) associated with the lowest crash cost (i.e., cost associated with injuries and property damage) and maximum cost-effectiveness for freeways. Crash data involving Kansas guardrail systems, which were compliant with recommendations provided in the 2006 AASHTO RDG and occurring on freeways with divided medians, were collected and analyzed. The frequency, rate, and risk of shielded hazard crashes were extremely low. RSAPv3 analyses indicated that there was an economic and safety benefit to reducing the installed LON as well as utilizing different runout lengths for left- and right-side departures for divided roadways.

Language: en