对于三线并行盾构隧道, 后行隧道多次侧穿会对已建先行隧道造成扰动影响. 基于Mindlin 解, 采用两阶段分析法, 得到了先行隧道在两次盾构平行跨越下的水平附加位移解析解. 与国家科学中心核心创新项目上海硬 X 射线三线并行盾构隧道现场监测数据进行对比,验证了方法的有效性. 对三线隧道水平净距、结构纵向刚度、地层损失率及地层剪切模量进行了影响因素参数分析, 研究结果表明: 先行隧道在后行隧道平行跨越关键断面下产生的水平附加位移峰值与并行隧道水平距离、隧道结构纵向刚度、地层剪切模量成反比, 与地层损失率成正比. 研究成果可为合理预测后行隧道侧穿施工对已建先行隧道的影响提供一定的理论依据.

In a three-line parallel shield tunnel, the construction of a second shield tunnel may affect existing advanced tunnels. An analytical solution for the additional horizontal displacement of the leading tunnel after two parallel side passes of the shield was obtained by establishing a two-stage analysis model and using the Mindlin solution. The effectiveness of the method was verified using measurement data from the Shanghai X-ray shield tunnel. A parametric analysis was performed to investigate the effects of the horizontal distance between the tunnels, longitudinal stiffness of the tunnel structure, shear modulus of formation, and ground loss on the tunnel responses. The results showed that the additional displacement peak generated by the first tunnel under the parallel side crossing of the second tunnel was inversely proportional to the horizontal distance of the parallel tunnel, longitudinal stiffness of the tunnel structure, shear modulus of the formation, and formation loss rate in direct proportion. The proposed method can provide a theoretical basis for predicting the influences of two parallel side passes of a shield on an existing advanced tunnel in relevant engineering practice.