Abstract
Due to the limited regulation in the construction of paratransit busses in the United States, manufactures are able to produce these busses with little regard to the crashworthiness of the vehicle. A paratransit bus consists of a custom built passenger cage installed on a chassis (including cab) produced by a major vehicle manufacturer. This lack of applicable crashworthiness standards pose a hazard to the passengers of these busses, as manufactures often use poor methods of construction to promote cost savings in production. As a result of this, the Florida Department of Transportation Transit Office has provided funding for research involving the safety evaluation of paratransit busses. The primary objective of this research was to develop a testing procedure to evaluate the performance of the two primary connections that comprise a paratransit passenger cage: roof to wall connection and wall to floor connection. The evaluation of the connections is done through the use of a testing apparatus instrumented with distance traducers and a load cell, from which the connections resistance as a function of rotation can be evaluated. From this, the energy absorption of different connections can be found. Evaluating the energy absorption of the connection over a range of motion, as opposed to simply looking at its peak resistance value, is critical as it accounts of the stiffness of the connection as well as its ductility. By conducting these tests, problematic designs are identified and modifications are suggested to the manufacturer for improved performance. The proposed testing procedure was accepted by FDOT in December 2009, as a major component of the pre-qualification process, which temporarily grants bus manufactures permission to sell paratransit buses to the FDOT pending further investigation. In addition to the experimental results of various connection constructions, one finite element model of a wall to floor connection is presented as well as a computational assessment of two sidewall structures subjected to an impact load.
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