BOUNCE-OVERS: FIXED OBJECT IMPACTS FOLLOWED BY ROLLOVERS. IN: OCCUPANT AND VEHICLE RESPONSES IN ROLLOVERS

Abstract

Bounce-over rollovers occur when a vehicle rebounds off a fixed object and overturns as a consequence. The rollover must occur in proximity to the object from which it is deflected. This chapter on bounce-overs is from a comprehensive textbook on occupant and vehicle responses in rollovers. The authors report on a study of U.S. crash data that was reviewed to evaluate the distribution of bounce-over crashes and injuries, initiation objects, and impact locations. Results showed that in passenger cars, bounce-over crashes account for 8.4% of rollovers but involve 36.2% of the seriously injured belted drivers. Most bounce-overs are initiated by contact with narrow objects such as a pole, tree, or barrier, or large objects such as a ditch or embankment. The authors developed a laboratory test to simulate a narrow object bounce-over; they report on the results of using this test. The information gleaned from the test provides a better understanding of vehicle kinematics and occupant injury responses. The test also provides input for the development and assessment of mathematical models of occupant kinematics and safety systems in bounce-over rollovers. The aim of the research was to determine minimum crash sensing requirements, not to simulate the life-threatening conditions of vehicle rollovers.