非对称结构作用下深基坑围护结构受力变形分析

Analysis of Stress and Deformation in Deep Excavation Support Structures under Asymmetric Structural Actions

摘要: 本文基于苏州地区某地铁车站的实际工程，采用数值模拟与现场监测相结合的方法，研究了非对称结构作用下深基坑围护结构的受力变形规律。研究表明：1) 非对称既有车站的存在使得结构对称的新建深基坑围护结构呈现非对称的受力变形规律。2) 既有车站对于基坑围护结构受力的影响程度与其所处位置与既有车站的距离有关，邻近既有车站侧地连墙较对侧地连墙拉应力增大，坑底以上压应力减小，坑底以下压应力增大。3) 既有车站的遮拦影响使得邻近侧地连墙变形量小于对侧地连墙，对称截面呈现非对称的变形特征，且非对称变形程度随着开挖的推进逐渐增加。

Abstract: In this paper, based on the actual engineering of a subway station in the Suzhou area, a combined approach of numerical simulation and on-site monitoring was employed to investigate the stress and deformation patterns of deep excavation support structures under asymmetric structural actions. The study reveals the following findings: 1) The presence of an existing asymmetrical station results in non-symmetric stress and deformation patterns in newly constructed deep excavation support structures with initially symmetric configurations. 2) The degree of the impact of the existing station on the stress in the excavation support structure is related to the distance between the station and the existing station, with increased tensile stress on the side adjacent to the existing station’s Earth- retaining wall and decreased compressive stress above the excavation bottom, while compressive stress below the excavation bottom is increased. 3) The obstructive influence of the existing station leads to smaller deformations in the Earth-retaining wall on the side adjacent to the station compared to the opposite side, resulting in an asymmetric deformation profile in the originally symmetric cross-section, with the degree of asymmetry increasing with the progress of excavation.