Study On Crash Simulation And Structure Optimization Of Motor Vehicles And Trailers Rear Underrun Protection Based On ANSYS/LS-DYNA

In recent years, as our country continued increase in car ownership, the number of road accidents also increased, the passive vehicle safety is increasingly a cause for concern. Therefore, how to improve vehicle passive safety performance to reduce or avoid a series of social and economic problems caused by traffic accidents have important practical significance.In the car crashes, the highest probability of crashes occurred in the automotive front and rear, particularly on the highway, large number of casualties caused by rear-end collisions. Therefore, the research on collision characteristics of motor vehicles and trailers rear underrun protection for improving the safety performance of automobile collision is of great significance. In this paper, to establish the finite element model of motor vehicles and trailers rear underrun protection of a domestic heavy trucks through computer simulation method as the prototype, according to our standard GB11567.2-2001 (Motor Vehicles and Trailers RearUnderrun Protection Requirements) make a simulation study of full width impact with a mobile barrier and to analyze the deformation and energy absorption situations of components of in the collision process. Under the circumstance which the crash simulation results do not meet standards, the stiffness of components through adjust the thickness of the tube by the small step values to meet standards, and then find the line with standard minimum thickness value, finally form the quantitative indicators which the rear protection device of rod-beam type is whether up to the standard.For the collision safety performance of the rear protection device to ensure a more reliable, this paper also making structural improvements to the rear protection device of rod-beam type through increasing the lateral bracing members, and making a comparison on simulation results between the improved rear protection devices and the not improved rear protection devices.Against the offset collision in the reality of the situation, the paper mainly to making a simulation study of 50% width offset collision with a mobile barrier to the improved rear protection devices, and forming the quantitative indicators of minimum thickness value to the improved rear protection device components.In addition to making a collision characteristics study in accordance with the requirements of the national standard to the rear protection device,the paper also making a comparison on energy absorption situations of the rear protection device components when them have a collision with the moving barrier,and making energy absorption study to the beam of protection--the main absorption component.Through the research on collision characteristics of motor vehicles and trailers rear underrun protection,the traffic management departments and other law enforcement agencies can determine whether the rear protection device meets the technical requirements of national standards by measuring the rear protection device components thickness value,to prevent the vehicles which installed the failure rear protection device entering the community.