Civil and Environmental Engineering



Ronald K. Faller

Date of this Version



Published in Journal of Transportation Safety & Security 7:1 (2015), pp. 1–19.


Copyright © 2015 Taylor & Francis Group, LLC and The University of Tennessee.

doi 10.1080/19439962.2013.846448


Crash cushions vary in geometry and cost. In this study, crash cushions were categorized in three different categories: redirecting with repair costs greater than $1,000 (RGM), redirecting with repair costs less than $1,000 (RLM), and nonredirecting sacrificial (NRS). Typically, RGM systems are less expensive initially, but life-cycle costs are high. RLM systems typically reciprocate this trend. NRS crash cushions (e.g., sand barrels) are generally less expensive but require total replacement after a crash has occurred, which may be impractical at high-traffic volume locations. Due to limited funding, there is often a need to identify the most cost-effective crash cushion category for highway scenarios with different roadway, traffic, and roadside characteristics. This study was commissioned to determine benefit-cost ratios for each crash cushion category in a wide range of roadway and roadside characteristics using the probability-based encroachment tool, Roadside Safety Analysis Program. Only RGM and RLM systems were cost effective for freeways and divided rural arterials, but all three categories competed against the unprotected condition on undivided rural arterials and local roads.