明挖地铁车站整体建模结构受力分析

Structure Stress Analysis by Integrated Modeling for Open-cut Metro Station

通过对目前明挖地铁车站设计中采用的计算模式———平面框架计算模型进行介绍,指出此种计算模式存在的不足,建议对此类重要工程应进行空间受力整体分析。结合工程实例,对明挖地铁车站结构受力机理进行详细分析,选取适合其实际受力的计算单元,利用大型通用有限元分析软件SAP2000对地下车站受力进行三维空间整体建模分析;指出基本组合及准永久组合对车站设计起控制作用,人防荷载和地震作用所参与的组合可作为检算工况;根据计算结果,得出结构最不利受力区域为板柱、板墙节点区域,大洞口区域出现应力集中现象,分布较为复杂;车站与风道接口处的结构布置需仔细核算,必要时应优化设备布置,保证结构安全。

Through the introduction for the plane frame model which is a calculation model adopted by open-cut metro station design at present,this paper points out the defects of this calculation model and suggests that the space model should be used for such important project.Further,in combination with an actual project,this paper selects the appropriate calculation units for the structure,analyzes the open-cut metro station of three-dimensional integrated modeling by the large-scale general-purpose finite element analysis software SAP2000.The analysis results show that: the fundamental combination and the quasi-permanent combinations will master the station design,and then the civil defense load and seismic load in combination may be considered as the check computation condition.The most unfavorable force regions are at the slab-column and slab-wall node regions,and the stress concentration occurs on the large hole regions in which the stress distribution are complex.The structure interface between the station and the wind tunnel should be inspected carefully,and the equipment layout should be optimized so as to ensure the structural safety when necessary.