Isolated obstacles in the road-verges of motorways cannot always be avoided. In order to prevent collisions with these obstacles a crash cushion or impact attenuator sometimes can be the only solution. In order to provide a construction adjusted for the European situation a crash cushion called the RIMOB (RIMpelbuis OBstakelbeveiliger) (crumple tube obstacle protection) has been developed. The RIMOB is composed of a nose segment and a series of interconnected deformable segments each comprising a box structure containing aluminium crumpling tubes. Both sides of the construction are formed by overlapping flank members in such a way that during a frontal collision there will be dissipation of energy. An evaluation carried out will be dissipation of energy. An evaluation carried out in 1989 indicated that: (1) the construction is very stable in both front and side collisions; (2) vehicles were restrained from going under or over the construction; (3) the vehicles came to rest within the length of the construction and there was not any noticeable rotation of the colliding vehicles; (4) risk to occupants of vehicles is substantially reduced when isolated obstacles are protected against collision with a RIMOB; and (5) the overall conclusion is that the cost benefit of the RIMOB as a road safety measure is confirmed. (A)
Abstract