水平往复荷载下橡胶板式支座剪切性能

Shear performance of rubber plate bearing under horizontal reciprocating load

为探讨灾难地震作用下空间网格结构支座节点的剪切性能,设计了橡胶板式支座模型,并对其进行竖向恒载下的水平大位移往复加载试验,获得了支座的水平等效刚度、屈服后刚度、屈服力及等效阻尼比等剪切性能指标。结果表明:锚栓是橡胶板式支座的薄弱部位;锚栓直径和竖向力是影响橡胶板式支座剪切性能的主要因素;当橡胶板式支座水平位移超过设计范围时,增大锚栓直径会使其水平等效刚度与屈服后刚度增大,而等效阻尼比与屈服力减小;随着竖向恒载的增大,支座的水平等效刚度、屈服后刚度及屈服力均增大,且等效阻尼比在加载中期大幅度下降,耗能能力增强。

In order to investigate the shear behavior of support nodes of space grid structure under earthquake disaster,a rubber plate bearing model was designed and tested under vertical dead load and horizontal large displacement reciprocating load.The horizontal equivalent stiffness,post yield stiffness,yield force and equivalent damping ratio of the bearing were obtained through the tests.The results show that the anchor bolt is the weak part of the rubber plate bearing.The anchor bolt diameter and vertical force are the main factors affecting the shear performance of rubber plate bearing.When the horizontal displacement of rubber plate bearing exceeds the design range,the horizontal equivalent stiffness and post yield stiffness increase with the increase of anchor bolt diameter,while the equivalent damping ratio and yield force decrease.With the increase of the vertical dead load,the horizontal equivalent stiffness,the post yield stiffness and the yield force of the bearing increase,and the equivalent damping ratio decreases significantly in the middle stage of loading,and the energy dissipation capacity increases.