Finite Element Stress Analysis On The Impacted Bridge And Research On The Anti-collision Device

With the rapid development of economy,the ultra-high and large vehicles become more and more popular.Due to lack of detailed supervision of the relevant departments and the driver is not high quality,the accident about ultra-high vehicle collision bridge structure occurs frequently.The incidents not only cause traffic disruptions and threat the safety of pedestrians and passing vehicles,but also cause serious damage to the bridge structure.In order to ensure the normal use of the bridge structure,we need to evaluate it.However,current researches are still relatively lacking.In particular,there is not specific formula for the calculation of the impact load.There is not specific reports about bridge structure anti-collision device.This paper which mainly studies on the above problems,which has important theoretical and engineering value to the collision of bridge structure design.This article bases on the nonlinear finite element program of ANSYS/LS-DYNA,combines with the practical characteristics of collision between ultra-high vehicles and the bridge,to choose appropriate vehicle and bridge element type,nonlinear constitutive relation of material,boundary and constraint conditions and establish an effective finite element model.This article carries out the whole calculation of collision process by the nonlinear finite element simulation.By changing the speed of the car and the weight of vehicle,we get the law of impact.Through multi-parameter curve fitting,this article obtain the impact force calculation formula about the weight and speed of vehicle.Finite element software is used to calculate the forces of the bridge structure,when it was hit by different weight and different speed.Through comparison,the variation of stress and deformation of bridge structure under different influence factors is obtained.Comparing and analyzing the time history diagram of impact force on the bridge structure which set and not set the anti-collision device,to provide a reference for setting anti-collision devic.