The most common types of motor vehicle accidents are frontal collision, side impact, rear impact and rollover [1]. Rollover accidents have higher death and injury rates as compared to the other accidents. In Spain between 1995-1999, only 4% of the accidents were caused by rollover whereas the death rate is almost 5 times of the others [2]. Due to the deformations on bus body, residual space may not be sufficient for passengers and crew, after rollover. That might cause having dead and injured people in a bus. Bus body strength is the most important factor saving passengers’ life during rollover and there are rollover tests to ensure the strength of bus superstructure. Bus rollover tests are conducted in accordance with FMVSS 220 in the United States and UN ECE R66 regulation in European countries. R66 has been applied to single deck rigid or articulated vehicles since 1986 and it is valid for passenger vehicles which are carrying more than 22 people, whether seated or standing [3]. In this study, the conformity of R66 to 12-meter electrical passenger vehicle E-ATA which is produced by Karsan Automotive, was investigated. 3 point bending and coupon tensile tests were made to determine the mechanical properties of material and for calibration, before rollover. Simulation results were analyzed by using Ls-Dyna. A body section of bus superstructure was simulated and then rolled over physically. Since the simulation and physical test results are similar, the entire bus superstructure was rolled over and analyzed with FEM model on Ls-Dyna.
Anahtar Kelimeler: Regulation, superstructure, deformation, residual space, rollover, FEM model
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