Study On Dynamic Response And Anti-collision Measures Of Vehicle Impact On Pier

With the development of our society,the number of overpass bridges is increasing rapidly,which also brings about the problem of more accidents caused by vehicles hitting the piers.Vehicle impact on the pier will not only cause casualties,but also threaten the safety of the bridge and affect the normal traffic operation.Therefore,the research on vehicle impacting on the pier bears has practical significance.In this paper,ANSYS / LS-DYNA finite element simulation software is used to study the problem.This paper reviews and analyzes the literature on vehicle impact on piers and anti-collision measures,including theoretical research,experimental research and finite element numerical simulation.This paper summarizes the theoretical analysis and research status of vehicle impact on bridge pier,and determines to use numerical simulation method to discuss vehicle bridge impact.Based on a flyover in Hefei,the finite element model of the bridge is established,and three kinds of vehicles with different mass are selected to build the vehicle model.The impact angle and impact velocity are controlled respectively,and the dynamic response analysis of vehicle impact on the pier is carried out by using ANSYS / LS-DYNA.The results show that the larger the impact velocity is,the greater the impact force peak is,and the earlier the impact force peak occurs;when the vehicle impacts the pier at 40° and 50° angles,the greater the threat to the pier is;when the impact velocity is the same,10t and 20t vehicles impact the pier The peak value of the impact force is not as large as that caused by 2T vehicles,which means that the peak value of the impact force is not determined by the vehicle mass,but from the whole impact force time history curve,the larger the vehicle mass is,the longer the impact duration is,and the impact force of the whole impact process remains at a higher level,the greater the threat to the pier.According to the model established above,the influence of stirrup spacing on the dynamic response of the pier is discussed.The results show that when the vehicle impacts the pier,the stirrup spacing of the pier is 200 mm,the threat is the least.The combination measures of foamed aluminum,steel plate and concrete and steel plate were established to verify the effectiveness of the anti-collision measures.The research shows that the combined measures of anticollision combined with aluminum foam and steel plate are better than those in the three aspects of bridge pier stress,vehicle impact force and pier top displacement.In this paper,through the finite element numerical simulation method,the dynamic response of vehicle bridge collision,the influence of stirrup spacing on dynamic response,the effectiveness of anti-collision measures and other aspects are studied,and the traffic safety problems are deliberately discussed,which has a certain reference value for the bridge structure design.