Development of Crash Modification Factors for Left Side Rumble Strips

摘要

This study evaluated the feasibility of adding rumble strips to the left side of rural dividedhighways in New Brunswick. A 6-year retrospective review of 406 crashes that occurred onRoute 2 and Route 95 from 2004-2009 was supplemented with an in-depth analysis of 289incidents that occurred on the Brun-Way owned and operated sections of Route 2 and Route 95during the years 2006–2011. The report revealed that despite significantly more traffic travellingin the right (outside) lane, a larger amount of run-off-the-road (ROR) crashes occurred to the left(non-rumble strip) side. The potential benefit of left rumble strip installation was developed bycomparing the safety performance of highway sections with right-side-only rumble stripinstallation versus known Crash Modification Factors (CMFs) developed from highways withrumble strips on both sides. A CMF that estimates the incremental benefit of installing a left siderumble strip in addition to an existing right side rumble strip was estimated to be 0.93 for all RORcrashes. In other words, installing a left side rumble strip (where a right one exists) would yield7% fewer ROR crashes. A conservative benefit-cost analysis revealed that the B/C ratio of theinstallation of left side rumble strips in New Brunswick ranged from approximately 14 to 20depending on the source dataset.