深厚软土地区深大管廊基坑围护结构内力分析

Analysis of the Internal Force of the Retaining Structure of the Deep and Large Pipe Gallery Foundation Pit in the Deep Soft Soil Area

为研究深厚软土地区综合管廊基坑支护内力分布特性,优化相关地区管廊基坑的结构设计,本文基于妈湾跨海隧道综合管廊深基坑工程,使用有限元分析软件MIDAS构建了综合管廊基坑三维数值模型,模拟某综合管廊深基坑在施工过程中的开挖和支护全过程。基于数值模拟的结果,分析不同开挖阶段下内支撑、临时立柱及地连墙结构内力的变化规律,为后续施工采取相应的变形控制措施提供参考。经过对计算结果的分析,可以发现基坑支护结构的内力和支护结构安全性在结构正常工作范围内,该工程基坑的支护结构方案和施工流程可以保证基坑稳定性。对于深厚软土地区的管廊基坑,支护结构的内力变化受地层土体性质影响比较大,在进行深基坑支护设计的时候,要重点考虑地层土体性质优化支护结构的布局,以保证基坑的安全。

In order to study the internal force distribution characteristics of the integrated pipe corridor foundation pit in the deep soft land area,the structural design of the pipe corridor foundation pit in the relevant area is optimized.Based on the deep foundation pit project of the cross-sea tunnel corridor in Mawan,this paper constructs a three-dimensional numerical model of the integrated pipe corridor foundation pit using the finite meta-analysis software MIDAS,and simulates the construction process of the pipe corridor foundation pit excavation and support structure in a certain period of time.Based on the numerical simulation results,this paper analyzes the law of change of internal support,temporary columns and internal forces in the structure of the ground wall under different excavation stages,and provides reference for the corresponding deformation control measures for subsequent construction.The results show that the internal force of the pit containing structure is under control,the structure is safe as a whole,and the design scheme of the containing structure can meet the requirements of the stability of the pit.Under the pipe corridor foundation pit in the deep soft soil area,the internal force change of the support structure is greatly affected by the soil properties of the formation,and when carrying out the design of the deep foundation pit support,in order to ensure the safety of foundation pit,the layout of supporting structure should be optimized by considering the property of stratum soil.