不同工况下地下连续墙内支撑支护结构的土压力

Soil pressure of bracing underground continuous wall internal support structure in different working conditions

目前在基坑支护设计时,土压力仍按朗肯理论进行计算,而现有的弹性抗力法模型的计算结果并未将基坑开挖的实际工况纳入考虑范围。通过理论分析,考虑基坑开挖卸荷应力路径,推导出地下连续墙内支撑支护结构土压力与位移之间的关系式;通过荷载增量法,计算出每种工况下挡墙的内力和位移表达式,采用Fortran语言编写了TPX程序,计算出了不同工况下支护结构的土压力及位移;以武汉绿地中心深基坑工程为例,采用Midas GTS软件对不同工况下支护结构的内力、位移和土压力进行了数值模拟分析。支护结构土压力和位移的理论计算值和数值模拟分析结果与实测值的对比结果表明其吻合较好,说明本文理论计算方法可行、实用。研究成果可为基坑工程的设计及施工提供一定的科学指导和理论依据。

Currently,the design of excavation support systems still relies on the Rankine theory for calculating soil pressures,and existing elastic resistance methods do not consider the actual excavation conditions in their model calculations.This paper presents a theoretical analysis that takes into account the stress path during excavation unloading,and derives the relationship between soil pressure and displacement on the support structure.By using the load increment method,the internal forces and deformation expressions of each retaining wall under different conditions were calculated.A TPX program was developed in Fortran language to compute the soil pressures and displacements of the support structure under various scenarios.The case study of the Wuhan Green Center deep excavation project was conducted using Midas GTS software for numerical analysis,examining the internal forces,displacements,and soil pressures of the support structure under different conditions.A comparison between the theoretical calculations of wall displacement and soil pressure in this study and the field monitoring data and numerical simulation results demonstrate good consistency,confirming the correctness and practicality of the proposed theory.