Research On Crashworthy Structures And Collision Safety For Metro Vehicle

With the development of rail vehicle technology, proactive protection technologies of train operation safety which means the ability to avoid the accident (including the crash) has ensured the safe operation of rail vehicles under normal circumstances. However, because of the complex system and the human machine interface of rail vehicles, some random issues, like technical defects、equipment failure、operator error and abrupt changes in the natural environment and so on, can lead to a train collision accident, thus, train collision accident is impossible to completely avoid. How to reduce the accident rate of train collision, improve the operation safety of train and finally realize the personnel and property protection has become a key technology in the design and development of modern rail train. In this paper, the railway vehicle passive safety protection problems which draw more attentions recently were studied on the basis of the rapid development of China’s rail transit as well as the increasing concerns on the security of vehicle transport from the whole society. The main research contents are as follows:Firstly, by means of experiment and simulation, the key technology of the energy-absorbing of typical energy-absorbing device for railway vehicle were studied, such as material constitutive model, strain rate effect, material property parameters, and structural mesh size in numerical simulation, and the influence laws of different factors on the structural energy-absorbing response were investigated, providing a basis for the improvement of calculation accuracy of evehicle crash worthiness.Furthermore, in this paper, research of a train collision’s response mechanism was carried out from the perspective of the collision dynamics of the vehicle:coupling collision model was firstly built up under two different conditions(1. Single-car crashes a rigid barrier; 2.car to car crashes), and the parameters of the relevant laws and regulations on vehicle passive safety in all countries were compared, time course of the characteristic curves of the velocity、 energy-absorbing、deformation、impact force flow and so on, of each car were obtained through the analysis of vehicle coupling collision. The inside relationship among the deformation, energy-absorbing and the impact force flow of the vehicle’s key collision device was analysised. Results show that, distribution pattern of the impact force flow is consistent among the same models of the vehicles, and has the significant difference among the different types of vehicles.A comparative study of the differences in response of different models in the same condition had been conducted, the relationship between the whole body of the vehicle and the key device on unitary absorbing ratio was studied, in order to straighten the deformation causes of the key device out, distribution ratio of impact force flow of every components were analysed, finally, the rail vehile frontal crash based on lumped-parameter model had been set up through obtaining the parameters of vehicle dynamic stiffness characteristics. The results provide the practical advice for rail vehicle safety design and can be helpful to guide the rail vehicle design.