Three-parameter Analysis On The Nonlinearized Modality Of Continuous Beam Bridge Anti-seismic LRB

Earthquakes occur frequently in recent years, it make a lot of bridges damaged,so how to prevent the bridge become more and more important. The purpose of the isolation design is to use the Seismic Isolator to increase the structure’s baisic cycle, to evade the earthquake concentrated area and to reduce seismic response.The LRB have it’s own advantages, and be used widely in the isolation design. Previous research treat the LRB simplified and only consider it’s equivalent stiffness and equivalent Damping.However,as the development of the finite element software,it make possible to build the nonlinear model of LRB. What’s more, the nonlinear model is better than other modle to simulate the LRB’s dynamic characteristics.therefore, the research of LRB’s nonlinear model is necessary and significant.This paper elaborate the LRB’s working principle and dynamic characteristics and discuss the theoretical analysis model.In this paper the selected bridges is a typical continuous bridge,the Hysteretic systems in the midas software can be used to simulate the nonlinear dynamic behavior of the force-displacement relationship for LRB.The nonlinear model of LRB have three parameters: initial stiffness Ku, stiffness ratio α, yield force Qy.By changing the three parameters’ value we can get the LRB’s work efficiency and it’s influence to the isolation piers and the non- isolation piers’ s seismic response.Put the results in a table.The standard of selecting the best parameters is to reduce the selected section’s seismic response.Comparing the effect,we can know that the appropriate parameters of LRB effeetively reduce the seismic response.