Abstract:Based on the nonlinear dynamic time history analysis,a slightly curved simple supported isolated bridge is studies,to investigate the characteristic and the rule of parameters of the lead rubber bearing ( LRB).Results show that the moment at the bottom of piers and the displacements of LRB to near fault earthquake ground motions are larger than those to far fault earthquake ground motions.It is efficient to reduce the response of isolated bridge to the near fault earthquake ground motions by isolation technology.The bearing displacement decreases with the increment of the initial stiffness and the yielding strength,while the moment at the bottom of the pier varies with the change of the different stiffness and pulse types.