Roadside barriers are designed to enhance the safety of the road infrastructure by containing errant vehicles and reducing the severity of off-path collisions. While conventional barrier systems have performed well for the occupants of passenger cars, their effects on the safety of other road user groups, especially motorcyclists, is not well understood. The main purpose of this feasibility study was to recommend a research method for investigating the interactions between motorcycles and road safety barriers. A review of the relevant national and international literature was conducted, revealing a relative lack of published material regarding the nature of motorcycle collisions both with roadside barriers as well as motorcycle crashes in general. Various features of barrier systems were identified in the literature as providing a significant safety risk to fallen motorcyclists, particularly barrier posts. There have been numerous strategies employed, mostly in Europe, to better protect motorcyclists from impacts with barriers, including the installation of additional W-beams, using impact attenuators to cover exposed barrier posts and substituting traditional IPE posts with more forgiving "sigma" posts. In addition, there have been several new barrier designs and/or modifications that have been developed and tested in Europe with promising results. Guidelines developed for the conduct of physical crash-tests with motorcycles were reviewed, and alternative methods, such as computer/mathematical simulations and component testing, were also considered. Based on the information from the literature review and subsequent consultation with several experts and stakeholders, recommendations for a multi-stage research program were made. (A)
Abstract