Abstract:In order to solve the construction problems of the shield section of Xiangjisi Road West Extension Project in Hangzhou passing under 220 kV Banxia Line, the power pipe trench of Banxia Line crossing the foundation pit (4# working shaft) of the tunnel at the east side of excavating section and the "L"-shaped intersection between the power pipe trenches of Ranxia Line and Ranwan Line and the foundation pit of the tunnel ate middle excavation, firstly, through the study on the influence scope of shield construction, the change law of surface heave and subsidence, and the evaluation of the adaptability of power pipe trench to surface deformation, the measures of optimizing tunneling parameters, controlling slurry pressure, tunneling speed, slag discharge, shield deviation correction, synchronous and secondary grouting are taken to protect the pipelines. Secondly, in order to reduce the construction difficulties, the on-site protection measures of steel I-beam jacking concrete cable trench and reinforced concrete cover plate supporting power pipe trench are adopted to protect the pipeline. After taking reasonable construction protection measures for 220 kV power pipeline, the excavation of the foundation pit of the tunnel is successful, and the shield starts on time, which not only saves the cost, but also shortens the construction period, and also provides a reference for the construction of similar projects in the future.