Effect Of Pounding Analysis Of Seismic Response For Long-span Suspension Bridge Between Main Span And Approach Span

Suspension bridge is a landmark building because of expensive and magnificent shape.Once damaged,it will cause serious damage to society and economy.In recent years,the pounding problems of the bridge in the earthquake is not uncommon and domestic and foreign scholars on the bridge pounding problems are mostly for small and medium span of the bridge but the long-span suspension bridge pounding problems is very little.And the impact of the pounding of the structure can not draw a more unified conclusion due to differences in ground motion and the structure of their own characteristics.The suspension bridge is a long-period structure,which is very different from the basic period of the bridge.The impact of the pounding on the main bridge is the main point of the seismic design of the long-span suspension bridge.It has a great significance to study the pounding problems under the action of the suspension bridge and provide more reference and basis for the seismic design of the long span suspension bridge.In this paper,a long-span suspension bridge in mountain area is taken as an example.The nonlinear time history analysis of the structure is carried out and the contact element method is used to simulate the pounding problems.The impact of the pounding on the seismic response of the main bridge of the suspension bridge is studied.The specific research contents are as follows:(1)Firstly,the theory of structural pounding problem and the method of simulated pounding are studied.The contact element method is used to analyze the pounding problem of the main span and approach span bridge of the suspension bridge.The linear spring element is used to simulate the pounding effect of the bridge.(2)Study the characteristics of the bridge and a reasonable choice of the type of simulate unit main bridge member,pile foundation and other boundary conditions and the contact unit is used to simulate the collision problem.The dynamic characteristics of the suspension bridge are calculated and analyzed.(3)The influence of collision on the seismic response of the main bridge of the suspension bridge is analyzed,including the structural impact force effect,the displacement response of the main beam,the displacement response of the tower and the internal force response of the tower bottom,and the influence of the collision on the seismic response of the main bridge of the suspension bridge is analyzed by nonlinear time history analysis.The influence of collision parameters on the seismic response of the structure and the influence of the structural bilateral collision on the seismic response of the main bridge are mainly studied.(4)The influence of pounding on the seismic response of the bridge is studied,including the effect of the structural impact force,the displacement response of the bridge beam,the displacement response of the top of the pier and the internal force response of the pier bottom are established by changing the corresponding dynamic characteristics.