Study On Applicability Of High Damping Rubber Bearings For Highway Bridges

In recent years,some isolation bearings are used for China's new bridges,the high damping rubber bearing has good ductility and energy consumption and no pollution to the environment,and the construction is convenient,it has broad prospects for development.At present,many scholars have done a lot of theoretical and experimental research on the working mechanism,design parameters,calculation formula and durability of the high damping rubber bearings,and obtained some valuable research results.However,the application of high damping rubber bearings in the actual engineering is few,making the selection and design of the supporting parameters in the bridge structure not perfect,which is not conducive to the popularization and application of high damping rubber bearings.This paper is supported by the research project of Shaanxi Provincial Department of Communications(13-21K): optimization of beam bridge constructional measures,the finite element model is established by numerical simulation,and the dynamic time history analysis of different bridges is carried out by using different earthquake time histories,study on the standard span box beam and T beam in the pier height and soil types,and the characteristic period of seismic intensity conditions,using high damping rubber bearing of bridge structure after earthquake in response to changes.The results show that the use of high damping rubber bearings makes the piers and the together,sharing the seismic action.With the change of the height of pier 5m~40m,the displacement of bridge abutment and the bending moment of pier bottom increase first and then decrease.When the pier height is low,the amplitude increases,and increases with the increase of pier height.With the change of soil type I~IV,the seismic responses of the bridge structure,such as the abutment displacement and the pier bottom moment,are increasing.With the change of seismic intensity of 6 degrees ~9 degrees,the seismic responses of the bridge structure,such as abutment displacement and pier bottom moment,are also increasing.On the other hand,according to the existing bearing calculating parameters,the results showed that the high intensity region of soft soil condition,bearing displacement generally exceed allowable displacement,some even more than the limit displacement,in view of the above displacement overrun,This paper took the support displacement as the control target,the first to gauge the bearing support stiffness increases,and then combined with the limit device and control excessive displacement of the beam device,improve the parameters of high damping rubber bearing selection table.The results of paper are expected to promote the existing seismic code support continuous improvement,and meet engineering requirements,meet the needs of our current isolation bearing development,provide reference for seismic design of high damping rubber bearing.