L形地铁换乘车站超深基坑支护结构设计优化分析

Design Optimization Analysis of Ultra-deep Foundation Pit Supporting Structure for L-shaped Metro Interchange Station

以福州地铁洪塘路换乘车站L形超深基坑为工程背景,采用Midas GTS有限元软件模拟了超深基坑的开挖和支护过程,对换乘节点处围护结构的水平位移、内支撑轴力和地面沉降进行了综合分析。模拟结果表明,在换乘节点处,将原设计的7道内支撑优化为5道内支撑的支护方案切实可行。将数值模拟结果与工程应用过程中的现场实测数据进行了对比分析。结果表明:换乘车站超深基坑采用分区隔断+5道内支撑的支护方案是安全可行的,其地下连续墙的水平位移值、内支撑轴力值和地面位移值均满足规范要求。

Taking the L-shaped ultra-deep foundation pit of Hongtang Road interchange station of Fuzhou Metro as the engineering background,the excavation and supporting process of the ultra-deep foundation pit is simulated by Midas GTS finite element software,and the horizontal displacement,internal support axial force and land subsidence of the enclosure structure at the interchange node are comprehensively analyzed.Simulation results show that it is feasible to optimize the original 7-lane internal support to 5-lane internal support at the interchange node.The numerical simulation results and the field measured data from the engineering application process are compared and analyzed.Research results show that it is safe and feasible to adopt the support scheme of partition+5-lane internal support for the ultra-deep foundation pit of interchange station,and the horizontal displacement value,internal support axial force value and land subsidence value of the diaphragm wall all meet the specification requirements.