# Study on the Influence of Collision Scene on the Energy Dissipation Process for Train Collision
## 1 Introduction  
In Europe, a series of train crashworthiness research projects represented by Traincol, Safetrain, Safetram, and Safe Interiors [1, 2, 3, 4] have contributed to the formation of EN 15227 [5]. In the design of train crashworthiness, China mainly refers to the collision scene in EN 15227, where the moving train collides with the stationary train, as shown in Table 1. However, there are many forms of train collision accidents. For example, on 16 May 2022, an incoming train collided with an outgoing train (a moving train collided with a stationary train) in Catalonia, Spain. On 23 July 2011, a rear-end collision occurred between the D301 train and the D3115 train in Wenzhou, Zhejiang. On 9 February 2016, two passenger trainscollided head-on in Bad Aibling, southern Germany (train head-on collision accident). Therefore, on the basis of the collision scenarios required by the existing standards, it is of great significance to improve the safety of train collision by analyzing whether there are differences in the energy dissipation process of train collision, the energy absorption of energy absorbing structure and the maximum average acceleration of vehicle under different collision scenarios. In previous investigations, in the parameter design of multi-level crashworthiness structure, the law of energy dissipation of longitudinal collision, and research of collision test of trains, designers or researchers mainly analyzed the collision scene as shown in Figure 1 according to EN 15227. In the parameter design of multi-level crashworthiness structure, [PERSON] [6] studied the contribution of each interface to the energy dissipation of train collision under collision scenario 1. The interface between the head car and the second car is crucial for kinetic energy dissipation in the collision between the two trains. [PERSON] et al. [7] discovered that the energy absorbed by the energy-absorbing anti-climbing device was 533 kJ in the collision process of two trains, accounting for 18.38% of the total energy, which played an essential role in the safety of train collision. [PERSON] [8] established a longitudinal collision dynamics model of trains with different marshaling forms under collision scenario 1 and analyzed the relationship between energy dissipation of each interface and train parameters, including marshaling quality, marshaling number and collision speed during the train collision process, the empirical formula for calculating energy absorption at the end of the head car and the end of the middle car was achieved. [PERSON] et al. [9] explored the energy dissipation of the energy absorbing structure based on the 1/7 scale subway train collision model; the energy dissipation form of the head car and the maximum deformation of the middle car was obtained. For the energy dissipation law of train longitudinal collision, [PERSON] et al. [10] used LS-DYNA to establish a longitudinal collision simulation model of the train, analyzed the problems existing in the existing vehicles, and applied the deformed tube energy \begin{table}
\begin{tabular}{c c c} \hline \hline  & **Collision Scenarios** & \\ \hline \multirow{2}{*}{1} & Front-end collision of two identical & \multirow{2}{*}{The same kind of train} \\ \cline{3-3}  & types of train sets & \\ \hline \multirow{2}{*}{2} & Front-end collision of two different types & 80 t truck \\ \cline{3-3}  & of train sets & 129 t regional train \\ \hline \multirow{3}{*}{3} & \multirow{2}{*}{Front-end collision between train and road vehicle} & 15 t deformable obstacle \\ \cline{3-3}  & & 7.5 t obstacle \\ \cline{3-3}  & & 3 t rigid obstacle \\ \hline \multirow{3}{*}{4} & The collision between a train and an obstacle whose center of gravity is lower than the bogie at the end of a train & Such as vehicles, animals, or sundries at level crossings \\ \cline{1-1} \cline{3-3}  & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Collision scenarios and obstacles in EN 15227. Figure 1: Schematic diagram of collision scenario 1.  
absorbing structure to the coupler system.