摩擦摆支座在地下地铁车站结构中的减震效果研究

基于阪神地震中大开地铁车站的破坏模式与成灾机理,借鉴地面建筑结构的减隔震设计理念,提出在地铁车站中柱顶部设置摩擦摆支座形成新型减震结构体系。通过建立土-地下结构整体二维数值分析模型,运用整体动力时程分析方法对比研究了摩擦摆支座不同滑道半径和不同摩擦系数工况下减震结构与原型结构在结构变形和截面内力等动力响应的差异。结果表明:柱端设置摩擦摆支座使得结构整体抗侧刚度减小,结构的水平变形呈现小幅增大趋势。当摩擦摆支座的滑道半径越大、摩擦系数越小时,中柱变形、剪力和弯矩值较原型结构均有大幅的减小。

SEISMIC MITIGATION EFFECT ANALYSIS ON FRICTION PENDULUM BEARINGAPPLIED IN THE UNDERGROUND SUBWAY STATION

Based on the failure mode and damage mechanism of the Daikai subway station during Kobe earthquake, this paper proposes a new seismic mitigation structure. The friction pendulum bearing is installed at the top of the central columns, using the seismic isolation and mitigation design concept of surface structures. The 2 D finite element models of soil-structure are analyzed, and then the seismic response of the original and proposed structure in different slide way radius and friction coefficient are compared by dynamic time history analysis method. The comparison results show that the new structure with friction pendulum bearing is softer than the original structure, resulting in a larger relative horizontal deformation. The deformation, shear forces and moments of the central columns are significantly reduced, when the slide way radius is large and the friction coefficient is small.