Analysis Of Crashworthiness Simulation Of High-Speed Train Intermediate Vehicle Bodies Based On Damage Model

Once the collision accident occurs in the high-speed train,it not only causes the damage of the structure of the vehicle,but also seriously threatens the safety of the passengers.The passive safety design of high-speed train is the last guarantee for the safety of passengers in the accident.Therefore,it is of great significance to study the simulation and analysis of the crashworthiness of the high-speed train.Once high-speed train collides,the car body is subjected to complex stresses such as shear,tension and compression,resulting in the failure of rail vehicle body.The occurrence of this fracture has a key impact on the crashworthiness of vehicle structure.Finite element analysis is an important way to study Crashworthiness of vehicle body.Using simulation software to study vehicle body structure deformation,energy absorption and failure mode can reduce exploitation expenditure and shorten exploitation cycle.However,there are still many problems in the practical application of the finite element software,and there are some differences between the simulation results and the experimental results.The reasons don't lie the FEM software itself but in the shortage of exact constitutive model used to describe the deformation behavior of materials and damage model used to describe the failure and fracture of materials.In this paper,the research object is the CRH380 high-speed train,mainly completes the following works:(1)The deformation and fracture behavior of 5083-O aluminum alloy at different strain rates was investigated by flat tensile tests.For realizing different stress state,different gap tensile specimens have been designed,the mechanical property and fracture behavior of aluminum alloy under different stress states conditions were investigated.The results show that the total fracture strain decreases with the increase of the three stress triaxiality,but it does not decrease monotonously.With the increase of the stress triaxiality,the material changes from the shear fracture mode to the dimple fracture mode.(2)Based on the experimental results,the damage and fracture behavior of aluminum alloy under different stress states were systematically simulated.The simulation and test results show that the MMC damage model can simulate the deformation and fracture behavior of the material.(3)The train car body and couple simulate models was established based on the high-speed train structural characteristics and technical parameter.The train vehicle body conform the EN12663 through the static verification.The crashworthiness of the coupler is analyzed according to the EN 15227 standard,The intermediate vehicle collision model is established?(4)The MMC damage model is applied to the vehicle body finite element model of collision analysis,The longitudinal response,lateral response and vertical responses of high-speed trains are analyzed.The collision response process of the vehicle body under the condition of material damage failure and no failure is discussed?...