Research On Designing Crashworthy Structure For Urban Rail Vehicle And Occupant Safety By Simulation Method

Since entering the 21st century, the urban rail transit construction in country advances rapidly. As the urban rail transit becomes more and more important in the public traffic, its safety problems have received more and more attention. When train collisions occur in the compeletion of transportation tasks, it is difficult to avoid occupant's lives being treatened. Research on the safety of vehicle collision, which has become main study topic in the area of urban rail transit, needs a number of tests and theory analysis. With the development of explicit finite element technology, it is a very good choice to adopt numerical simulation test method to do research on crash problem.Passive safety study on urban rail vehicle at home and abroad has been widely concerned and deeply researched. Many research results have been applied to practical vehicles. But in China, there is almost no research on how to design crashworthy structure for urban rail transit according to its characteristics and how to verify its crashworthiness by simulation method. Furthermore, how to fit the relationship curve between the head injury criteria HIC or chest injury criteda with the secondary initial velocity by a function express is unknown at home and abroad. Therefore, it has not only academic significance but also practical value to explore the deformation rule of urban rail vehicle collisions, design crashworthy vehicle structure and research the second collision response of crews.To improve urban rail vehicle design levels and safety features and minimize the crew injury during impact, we will research the above problems based on the Jinbin urban rail vehicles in Tianjin in the thesis. Detailed works can be described in the following:Firstly, the complete CAD and FEM mode of the jinbin urban rail vehicle in Tianjin was established. Then, the static strength and modal of the vehicle under various operating conditions were analyzed by finite element method. The accuracy and availability of the numerical model was verified by comparing the numerical results with tests.Secondly, a new type of crashworthy body structure for urban rail vehicle was designed by using collision safety design concept based on the energy absorption performance of the thin-walled tube and the collision behavior of the Jinbin urban rail vehicle in Tianjin. Then, the numerical simulation test of crashworthy body structure was conducted by using PAMCRASH software. From comparison of the simulation results between crashworthy structure and origin structure, it showed that crashworthy body structure can realize stable and orderly deformation with Multi-absorption system under different collision speeds, and achieve ideal impact resistance properties.Finally, the second collision response of crews under crashworthy structure and origin structure was studied by using PAMCRASH software. The results show the crashworthy body structure make the injury of crews in the range of American specifications. In addition, the injury of crews under the different secondary impact velocities was studied, and the curves of HIC and chest acceleration with the secondary impact velocities were achieved. Through the curves, if the new designed structure plays safety protection role under test collision speed can be preliminarily judged. Then, the times of simulation is decrease.