Mechanical Properties And Optimization Analysis Of Friction Pendulum Base Isolation Structure

Friction pendulum bearing is a kind of isolation device which can consume seismic ergy through friction sliding.Because of its unique arc sliding surface,it can effectively limit the displacement of the isolation bearing,and automatically recover to the original position ter the earthquake.In recent years,with the continuous development of isolation technology,friction pendulum bearing has been gradually applied in isolation structure engineering at ome and abroad.In this paper,based on the nonlinear vibration differential equation of the friction pendulum base isolation structure,the dynamic response of the structure is analyzed by numerical method.The response surface method is applied to optimize the isolation structure of friction pendulum foundation.The main contents of this paper are as follows:Starting from the movement of the bearing,the mechanical properties of the bearing are studied according to its dynamic strong nonlinear vibration differential equation.With the help of Matlab mathematical calculation software,the calculation program of the dynamic response of the friction pendulum isolation structure is compiled,and the influence rules of different bearing parameters(slide radius 0.5m,1M,1.5m and 2m,friction coefficient 0.05,0.1,0.15 and 0.2,respectively)on the acceleration,velocity and interlayer displacement of the base isolation structure are analyzed.The base isolation structure and the structure without isolation measures are also analyzed The dynamic response was compared and analyzed.At the same time,when the friction radius is 2M and the friction coefficient is 0.05,the time history of the isolation layer,the first layer and the top layer is analyzed.The variation law of seismic wave which affects the time history of floor is obtained.A four story single frame structure model is established,and the parametric calculation and analysis of the friction pendulum isolation structure are carried out by changing the linear stiffness,nonlinear stiffness,effective damping,friction radius,friction coefficient and design displacement in the parameters of the isolation support.According to the principle of miscellaneous sampling method,using the software of design expert,the samples of relevant parameters of friction pendulum bearing are obtained,and the corresponding dynamic response of multiple groups of samples is obtained through structural analysis.Through the analysis of parameter significance,the determination of complex correlation coefficient of response surface regression model,and the probability of residual distribution,the fitting degree of response surface function model is determined to meet the accuracy requirements of parameter optimization.The example analysis also shows that the accuracy of the ptimization result meets the requirements.The research in this paper provides a useful reference for the design of base isolation structure of friction pendulum.