Study On Seismic Pounding Mitigation Of High-pier Bridge With SMA-PRM Dampers Based On Substructure Test Method

In fact,the seismic damage of engineering structures often occurs in some parts or components,the other parts are still in good condition.As the latest structure seismic test method,substructure test method can be described as follows: A structure is divided into experimental substructure and calculation substructure.The experimental substructure is expected to behave complex nonlinear during seismic loading,and it is tested in the laboratory.The calculation substructure is expected to remain linear during seismic loading and can be using numerical simulation method by computer.This method combines physical experiment and numerical simulation,not only simulate the real seismic response of structure,but also reduce the requirements for test equipment and test models.In this paper,based on the basic idea of substructure test method and the shaking table test of a high-pier bridge steel model,the substructure test method simulation program is established and verified by Matlab/simulink.Then the vibration efficiency of shape memory alloy pseudo-rubber metal(SMA-PRM)damper on seismic pounding of a high-pier bridge is studied by this program.The main research work of this paper are as follows:(1)For study on the mechanical properties of SMA-PRM damper,the cyclic loading tests with different frequencies and displacement amplitudes were carried out.Then the constitutive relationship model of SMA-PRM damper is established based on the results of cyclic loading tests.(2)Based on the basic idea of substructure test method and the results of shaking table test of a high-pier bridge steel model,the substructure test method simulation program of the high-pier bridge with SMA-PRM dampers is established and verified by Matlab/simulink.The numerical simulation of substructure test method is achieved.(3)Based on EI Centro,Taft,and artificial ground motions from the shaking table test of the high-pier bridge model,the simulation analysis of substructure test are carried out by the substructure test method simulation program.To study The seismic pounding mitigation of the SMA-PRM damper on high-pier bridge,the results of simulation are compared with the results of shaking table test of high-pier bridge which pounding gaps are 0.01 m and 0.015 m.Results show that the SMA-PRM damper can prevent the seismic pounding of the adjacent bridges,reduce the seismic response of high-pier bridge,improve the seismic performance of the high-pier bridge.