Optimization Of Mechanical Performance Of New Type Bearings And Its Influence On The Damping Ofbridges

Traditional potted rubber bearings are widely used in bridge structures as a shock absorbing and energy-consuming device,but their energy dissipation capacity is limited and their limit ability is limited.Traditional potted rubber bearings ca nnot meet the seismic performance requirements of structures under large earthquakes,resulting in serious damage to the bridge structure.Based on the design of traditional basin-type bearings,combined with the form of force of X-shaped steel dampers,a new type of support-X-shaped steel damper basin support is proposed.In order to meet the seismic performance requirements of the structure,the new bearings should have the characteristics of obvious shock absorption,stability,proper horizontal stiffness,and strong limit function.The work performance of the new bearing is analyzed by pseudo static test.The results show that the energy consumption of the new bearing after optimization has been significantly improved,and no sudden load drop has occurred during the entire loading process.From the hysteretic curve,it can be seen that the new bearing has the function of energy dissipation in stages,which can not only meet the free deformation of the structure under normal use load,but also play an effective damping effect under the earthquake.A 4 span continuous girder bridge is used to analyze the seismic performance of new bearing in the earthquake.The dynamic analysis method is used to study the internal force response of the bridge pier and the changes of the relative displacement between the pier beam under the E1 earthquake and E2 earthquake.The results show that the new pedestal can reduce the internal force response of the fixed piers and adjust the internal force distribution of the piers,and control the relative displacement of the pier beams.The influence of the yield strength of the damper on the internal force response of the pier is analyzed.The study found that: with the increase of yield damper force,internal force form of bridge pier increase gradually.Therefore,suitable dampers should be selected in seismic design to achieve optimal seismic performance.