Simplify Design Method of LRB Isolated Bridge subjected to Strong Earthquake

Based on the equivalent linear method and the equivalent plastic hinge theory,regular continuous bridge structure is simplified as the single degree-of-freedom system according to the dynamic performance of the lead rubber bearing(LRB)isolated bridge and non-linear characteristic of LRB and pier when LRB isolated bridge experience strong motion,and the equivalent stiffness and damping ratio of the system are estimated.The displacement of gird and top of pier are choosed as target displacement,and displacement-based seismic design is presented by using the revised displacement response spectrum which has long period and high damping.Finally,design example is shown,and compared with the design result and the elastoplasticity time history analysis result using the SAP2000 computation,it satisfies project accuracy requirement,and is suitable for preliminary analysis and design of regular LRB isolated bridge under the different performance level,and can provide the reference for earthquake response analysis of regular LRB isolated bridge under strong motion.