Safety Assessment of the Impacts of Foundation Pit Construction in Metro Station on Nearby Buildings

摘要

During the construction of metro station, it is important to ensure the safety and normal use of nearby buildings. Focusing on a foundation pit project in Hefei Metro, this paper fully examines the foundation type, structural form, construction period and use state of a nearby building, and explores the relationship between foundation pit support plan, metro station construction plan, and the residual deformation capacity of the building foundation. Based on the design files and different construction plans of the station, the finite-difference method and deformation observation were adopted to analyze the foundation settlement and residual deformation of the nearby building during metro station construction. The support plan and construction plan were adjusted and improved continuously. Finally, it is planned to support the foundation pit with reinforced concrete retaining piles and four-layer steel supports, and excavate and reinforce the pit layer by layer. Under the final plans, deformation of the building foundation does not exceed its remaining deformation capacity. This research provides an effective construction plan for the metro station, and specifies the way to observe the foundation settlement of the nearby building. The research results provide a good reference for similar risk projects to conduct safety assessment and evaluation in the design and construction phases.