Study On The Shock Absorber Displacement Control Effect Of The Bridge Considering The Friction Force At The Movable Support

The occurrence of the earthquake is a great threat to the safety of the bridge structure,if the bridge damage and loss of function in the earthquake,in addition to causing casualties and property losses,will also affect the disaster relief work.So the research on the damage of the bridge structure,on the adverse effects of the study on the friction at movable supports,on the low cost and easy replacement of seismic isolation device to reduce earthquake losses,ensure smooth traffic after the earthquake is the major theoretical and practical significance.This paper studies the effect of the bearing on the seismic response of the bridge structure,mainly focused on the the kinetic interaction effect on the elasto-plastic seismic responses of continuous girder bridges,and puts forward the new seismic isolation device to prevent and control the displacement of the beam beam falling and not significantly increase the seismic response of the bridge structure.The friction at movable supports can be transmitted to the fixed support piers through the main girder,which can cause the kinetic interaction between the piers,in the earthquake.In order to research the kinetic interaction effect on the elasto-plastic seismic responses of continuous girder bridges,taking into account the friction between the main girder and movable supports and the elastic-plastic state of the bridge piers may enter,finite element models of continuous girder bridges with different pier height were established.A nonlinear time-history analysis was done to analyze the maximum curvature of the fixed pier bottom under different schemes,finding out the case that the friction effect at movable supports cause the seismic performance of the fixed support piers unfavorable.Through the analysis of speed time history curves of pier top excited,the results indicate that if the friction passed by main girder to fixed supports coincides in the direction of vibration of the fixed support piers,the friction at movable supports may become unfavorable regarding the seismic response of the fixed support piers.Studying the effect of the kinetic interaction between the piers on the elasto-plastic seismic responses of continuous girder bridges,is very important to ensure the overall structure of the bridge has enough seismic performance.Setting the seismic isolation device is an effective measure to improve the seismic performance of bridge structure.However,the seismic design of the structure is mainly based on the single line of defense,which can not meet the requirements of the energy consumption and intensity of the bridge structure.Therefore,the paper is based on the existing structural measures,with the principle of "multi line of defense,separation of functions,step by step",using the design method of separating the energy dissipation component and the strength component,proposing a new structural system of the shock and displacement control absorber.This paper theoretically analyses the work process of the shock and displacement control absorber and the unit recovery force graph at each stage.On the finite element simulation,this paper takes a continuous girder bridge as the engineering background,comparative analysis of the finite element models of five different situations,found that the shock and displacement control absorber than the single line of defense is more conducive to improving the seismic performance of bridge structures from energy and strength.Combined with the design principle of the shock and displacement control absorber,in order to research the influence of parameters on seismic performance of bridge structures by adjusting the size of the main parameters that affect the damping effect.Proposing the new structural system of the shock and displacement control absorber is helpful to improve the seismic capacity and seismic resistance of bridge structure.