1Department of Mechanical Engineering, TOBB University of Economics and Technology
2Department of Civil Engineering, Mustafa Kemal University
3Research and Development, TEMSA Global, Turkey
Abstract
Safety of vehicle occupants jeopardized during rollover accidents when necessary safety measures are not taken. Structural adequacy and protection of occupants are the two significant measures that can be implemented to minimize occupant injury risk during vehicular rollover events. The aim of this paper is to evaluate the structural resistance and passenger injury risks and compare the effectiveness of safety belt usage in occupant during a simulated rollover event of a 13 meter long TEMSA bus. A total of eight occupants were placed at the structurally weakest locations of the bus. Three different occupant protection cases were considered: i. no safety belt, ii. two-point safety belt and iii. threepoint safety belt. A standard rollover procedure was simulated using non-linear finite element code LSDYNA. Head injury criteria and neck forces were calculated and compared to evaluate the effectiveness of seat belt usage on occupant protection. Simulation results clearly illustrated that when occupants had no seat belt protection they suffered serious risk of injuries. Moreover, two and three point safety belts provided somewhat similar protection levels for most of the occupants. Based on the findings, use of two point safety belt in all of the seats of the TEMSA busses was recommended.