Simulation Method for Couplers and Buffers in Train Collision Calculations

In order to study the behaviors of couplers and buffers (CABs) accurately in the process of train collision, a new simulation method for analyzing the characteristics of CABs was proposed based on the discrete beam in LS-DYNA. This method was then verified through a case study where a head to head collision between two identical subway trains marshaled by 6 cars occurred under a scenario with a relative speed of 36 km/h. The CABs' loading and unloading conditions, as well as their failure and falling-off behaviors under the ultimate load were simulated, and the contribution of CABs in the total energy absorption of the train collision was analyzed. The results show that the proposed method can simulate effectively the mechanical properties of CABs and couplers' failure and falling-off behaviors in the train collision. In addition, it can be used to obtain the indexes such as output characteristics and energy absorption of CABs in different positions. During the train collision, the energy adsorbed by the CABs accounts for 27% of the total energy.