地铁框架-管涵式车站结构三维地震响应分析

Three-dimensional seismic response analysis of subway station with frame-pipe culvert structure

上海地铁14号线静安寺站拟采用"两端明挖-中间顶管暗挖"的复合工法建设,该车站两端三层框架结构与中间顶管隧道结构存在刚度突变、平面及竖向不规则的特点。通过建立地层-结构的三维有限元数值模型,分析了设防地震工况下该车站结构的动力响应。计算结果表明:车站两端框架结构的关键受力部位为中柱的柱端和底板与侧墙的交角;车站A区框架的内力响应要小于C区,而C区框架的层间位移更小;车站中间的顶管段,其与两端框架结构的连接处断面、以及与联络通道连接的部位应力也较大;设防地震下,车站两端框架结构和中间顶管隧道结构的最大位移角都在规范限值以内。

Shanghai metro line 14 Jingansi station will be constructed by the composite construction method of "open excavation at both ends and intermediate pipe jacking".The three storey frame structure at the two ends of this station and the middle pipe jacking tunnel structure have the characteristics of abrupt stiffness,irregular plane and vertical direction.By establishing the three-dimensional finite element numerical model of stratum structure,the dynamic response of the station structure under the condition of seismic fortification is analyzed.The computational results show that the key parts of the frame structure at the two ends of the station are the column ends of the middle columns and the joints of the bottom plate and the side walls.The internal force response of frame A in the station is less than that of frame C,while the inter-story displacement of frame C is smaller.At the junction between the middle pipe jacking and the two ends of the frame structure,and the connection of the middle pipe jacking and connecting passages,the stress is larger.Under the condition of seismic fortification,the maximum inter-story drift of both frame structure at the ends of station and the middle pipe jacking tunnel structure are all within the specification limits.