地连墙施工环境效应与预测方法研究

Research on environmental effects of diaphragm wall construction and prediction methods

为探讨地连墙施工环境效应问题,在宁波轨道交通4号线盾构工作井地连墙施工期间进行跟踪监测,分析了地连墙施工全过程中土体水平位移、地表及周边建筑竖向位移的变化规律。在此基础上,根据地连墙墙幅灌注混凝土后的槽壁边界条件,提出了计算地连墙混凝土灌注引起土体位移的简化边界元法,通过计算与实测结果的对比,验证了方法的合理性,并进行了相关的参数分析作为对实测结果的补充。结果表明:地连墙施工环境效应由槽壁受荷状态改变引起,其影响程度与施工工艺、地质条件及开槽尺寸等因素有关。

A tracing monitoring during the construction period of diaphragm wall of the shield work shaft for Ningbo rail transit line 4 was carried out to investigate the environmental effect of diaphragm wall construction, and the change law of horizontal displacement of soil, vertical displacements of ground surface and surrounding building was analyzed in the whole process for diaphragm wall construction. On this basis, a simplified boundary element method was presented to calculate the soil displacement caused by pouring concrete according to the boundary condition of slurry wall after concreting, and the calculation result was compared with the measured result to verify the reasonability of the method, and corresponding parameter analysis was carried out as a supplement to the measured result. The results show that the environmental effect of diaphragm wall construction is caused by the change of the load state of the trench wall, and its degree is related to the construction technology, geological conditions and slotting dimension.