高烈度地震区曲线连续梁桥的减隔震方案研究

Seismic Isolation Scheme of Curved Continuous Girder Bridge in High Earthquake Intensity Area

结合高烈度区铁路曲线连续梁桥的工程实例,通过引入减震率对铅芯隔震橡胶支座、双曲面球型减隔震支座以及双曲面球型减隔震支座+黏滞阻尼器3种减隔震方案进行对比分析。结果表明:在多维地震动作用下,3种减隔震方案均具有良好的减震效果,采用双曲面球型减隔震支座+黏滞阻尼器的方案既可有效发挥双曲面球型支座摆动摩擦耗能,又可通过黏滞阻尼器限制最大位移,从而减少了双向耦合作用,延长了结构周期。同时,该方案可有效减少固定墩的最大地震响应,将地震荷载均匀分配至各墩,并充分发挥双曲面球型隔震支座的自复位功能,对震后的修复十分有利,是最优方案。

Combined with the engineering example of a curved continuous girder bridge in high earthquake intensity area,three seismic isolation schemes were analyzed by introducing the damping rate,including lead rubber bearing isolator,double spherical seismic isolation bearing,and double spherical seismic isolation bearing+viscous damper.The results show that three seismic isolation schemes have great damping effect under the multiple seismic excitations.T he scheme of double spherical seismic isolation bearing+viscous damper,which can effectively play the double spherical bearing swing friction energy dissipation,but also through the viscous damper limits the maximum displacement,thereby reducing the bilateral coupled effect,prolong the structural cycle.At the same time,the proposed scheme can effectively reduce the maximum seismic response of the fixed pier by assigning the earthquake load to each pier.The self-reset function of double spherical seismic isolation bearing is fully exploited.The scheme is very beneficial to the rehabilitation after earthquake,which is the best for the three schemes.