Analysis of Concrete Median Barrier Impacts

Concrete Median Barriers (CMB’s) are used extensively on the roadways of North America. They are most often used as permanent barriers on major freeways and highways and as temporary barriers in roadway construction zones. A drive along most stretches of roadway where CMB’s are in use will reveal multiple instances of automobile impact evidence. In this paper the characteristics of automobile impacts with CMB’s are analyzed. Specifically, the case of a yawing, side-slipping vehicle impact, where significant frontal engagement may occur, is considered. Typical damage patterns and residual crush profiles are reviewed as well as vehicle Delta-V, and Barrier Equivalent Velocity (BEV). Frictional energy losses, due to vehicle and CMB interaction, and their significance in the reconstruction of this type of collision are discussed. The vertical velocity component induced by the CMB in this type of impact is also examined.