Crash safety assessment of bus operators in mass transit buses

Abstract

Mass transportation systems and specifically bus systems are a key element of the national transportation network. According to the Traffic Safety Facts report from 1999-2001, total of 333 fatal involvements of transit bus operators in fatal crashes have been reported from 284,000 bus related traffic accidents. Thus bus occupant safety research is an effort for the enhancement of bus operator safety. Crashes resulting in injuries were distributed between front, door side, driver side and rear collisions. This study is aimed at the evaluation of potential bus operator injuries during different accident scenarios of a mass transit bus in frontal, side and rear crashes. Dynamic sled tests of the bus operator and its environment are first conducted at National Institute for Aviation Research. From Numerical models of the crash event including bus and bus operator are developed using the MADYMO and LSDYNA codes, and validated against the experimental sled tests. Validation is carried out by comparing the kinematics of the bus operator represented by a Hybrid III ATD in actual sled tests and simulations. To ensure validity, a comparison of various acceleration profiles and forces -moments experienced by the bus operator under various test conditions are compared. Furthermore, potential injury levels sustained by the operator in the actual sled tests and the simulations are compared with FMVSS standards. This is done to analyze biomechanical performance under different loading conditions. The developed models once validated for their realistic applications, are performed with parametric study to obtain optimized configuration that provides protection to bus operator in the course of a crash.