Effect of simulation accuracy of shear keys shear state on seismic response of friction pendulum bearing

Abstract

In order to study the effect of simulation accuracy of shear keys shear state on seismic response of friction pendulum bearing, a vertical spring-friction system composed of equivalent components is used to simulate the friction pendulum bearing effectively, and two numerical calculation programs are developed. A spring element with life-and-death characteristics is used to realize the simplified simulation of shear keys shear state in the program 1, while shear keys on both sides of the friction pendulum bearing in the same direction are considered independently in the program 2. By comparing the seismic responses of the two programs with different shear key shearing force, vertical spring stiffness and different peak ground acceleration (PGA) conditions, it can be concluded that the precise simulation of shear keys shear state can more accurately calculate the shear key shear time and the maximum acceleration of the structure, which is beneficial to seismic isolation design. When the shear key shearing force is large and the PGA is small, the relative displacement response of bearing will be small if the shear keys are simultaneously sheared off. Increasing the stiffness of the vertical spring can reduce the residual displacement of the friction pendulum bearing. The simulation accuracy of shear key shear state has little influence on the relative displacement response when the equivalent stiffness of friction pendulum bearing is large. In this case, the shear key shear state can be simplified.