地铁车站工程应用双向RFPS支座隔震效果研究

Isolation effect analysis on bidirectional RFPS bearing applied in the metro stations engineering

基于阪神地震中地铁大开站的震害机制，借鉴地面隔震建筑的研究成果，提出了地下结构中柱柱顶设置辊轴摩擦摆（RFPS）隔震支座的设计理念，根据拉格朗日方程推求了该隔震系统的运动方程，并运用Newmark-β时域逐步积分法对其求解。研究结果表明：尝试在地铁地下结构抗震设计中，采用隔震设计的理念在理论上是可行的；RFPS隔震支座具有良好的耗能和自复位特性，较长的自振周期使其具有必要的震动隔离能力；地铁车站中柱柱顶设置RFPS支座后，可以大幅度减少结构（尤其是中柱）的内力和变形，且无需担心隔震部位会出现大变形；适当选取圆弧滑道半径和滚动摩擦系数值，隔震效率可达到50％～70％。

In Kobe earthquake, the metro stations are damaged severely. Based on the columns damage mechanism of Dakai metro station and the research results of the ground isolation building, a design concept which setting roller friction pendulum （RFPS） isolation bearing on column pillars of underground structures were put forward. A theo- retical analyzing approach of the seismic isolation systems was derived based on the Lagrange equation, and New- mark-β method was used to getting the solution of equation. Research result shows that trying to adopt isolation de- sign idea in the subway underground structures is feasible in theory. The RFPS system posses good energy dissipa- tion and reposition capability, and the rather long vibration period provides the necessary isolation capability. The internal force and deformation amount resulting from seismic action could be drastically decreased on the subway station in the column with a RFPS system, and a large deformation wont appeared on the isolation parts. If an opti- mum combination of slide radius and a rolling friction coefficient is adopted, and the seismic isolation effect could be as high as 50% -70%.