Seismic Analysis Of A New Type Of Seismic Isolation Bearing For Railway Bridges In Hig Bridges In High Seismic Intensityregion

The earthquake is one of disasters that threat our life and property safety,whether the bridge has a good seismic performance has been the focus engineering design staff concern.Seismic reduction and isolation technique of bridge is mainly through using reduction and isolation bearing to design,it is a kind of technology that can effectively reduce the seismic damage to bridge structure.The commonly used bearings conclude layered rubber bearing and lead rubber bearing and sliding friction rubber bearing,high damping rubber bearing and steel damper bearing,and so on.This paper take the study of seismic reduction and isolation about the domain of railway bridge seismic isolation reducing isolation in Kunming as background,then select existing steel damper bearing and design reasonable parameters,determine the optimized parameters through the analysis of large span span continuous beam isolation of earthquake.After this,considering the influence of temperature change on the structure of large span concrete continuous beam and the effect of the damping bearing,a new type of seismic isolation bearing which can adapt to the temperature change is designed on the basis of the existing damping bearing.Through dynamic process and method of energy analysis,comparative study of new bearings and existing steel damper bearing under different seismic waves reduce isolation effect,that a new type of seismic isolation bearing in being able to adapt to the deformation of the temperature of the bridge,at the same time,not only did not eliminate the existing steel bearing damping isolation effect,even in many cases damping effect is slightly better to install the original support bridge.Specific research contents:(1)Give an overview of current bridge seismic isolation method for the progress of the study and show the characteristics of the project method though comparison;according to the typical bridge site conditions and seismic fortification intensity or high intensity earthquake bureau special ground motion analysis report in high seismic intensity area of large span continuous railway bridge,parameters are determined.(2)The finite element model of long span continuous bridge is established and the nonlinear numerical model is established to simulate the nonlinear relationship between the restoring force and relative displacement.The finite element model of large span continuous bridge is established to input seismic wave,and the dynamic response of the bridge is calculated.(3)Use the energy method to analyze and determine the design parameters of ordinary seismic device of railway bridge in high intensity region,determine the general parameters for the optimization parameters of isolation bearing.In the optimum condition,analysis the seismic effect between long span continuous bridge that using existing steel damping bearing and non isolation under the condition of large-span continuous girder bridge.(4)Design new isolation device on the base of existing steel bearing damping optimization parameter and determine its parameters.Make a seismic checking according to the specification of the bridge and compare with seismic performance of the bridge without isolation device.Finally,the isolation effect of the new type of vibration isolation bearing and the existing steel damping bearing is compared and the advantages of the new isolation bearing are explained.