液化场地装设粘滞阻尼器的桩基－结构体系抗震性能分析

To investigate the effect of viscous damper on the seismic performance of pile group-soil-structure in liquefiable soil under earthquake action. Firstly, build a three-dimensional numerical model of pile group-soil-structure in liquefiable soil by OpenSees finite element platform, and the reliability of the model is verified based on the centrifuge test results. Then, the Maxwell model was selected to simulate the mechanical properties of the viscous damper, and the parameter sensitivity analysis of the viscous damper was carried out to determine the suitable parameter value of the viscous damper under the condition of liquefiable soil. Finally, the influence of the overlying non-liquefiable soil layer on the damping design of viscous damper in liquefiable soil is analyzed, and the differences between the damping design of viscous damper in liquefiable soil and non-liquefiable soil are compared. The results show that the viscous damper can effectively reduce the seismic response of pile group-soil-structure system in liquefiable soil. It reduces the seismic response of the superstructure and the bottom of the pier. The overlying non-liquefiable soil layer affects the range of the optimal value of viscous damper in liquefiable soil. The suitable values of velocity exponent α of viscous dampers in non-liquefiable soil and liquefiable soil are 0.5～0.9, while the suitable values of damping coefficient C are significantly different. Compared with the non-liquefiable soil, the viscous damper can better reduce the seismic response at the bottom of pier in the liquefiable soil. The research results can provide an important basis for the design of viscous damper for pile group-soil-structure in liquefiable soil.