Application of Solid Concealed Bracing in Deep and Large Foundation Pit Engineering in Soft Soil

Taking a project near Yangtze River and railway in Wuhan as an example, the mixing pile reinforcement was used as concealed bracing for supporting in foundation pit engineering under the conditions of deep and weak stratum, limited surrounding environment and strict deformation control. This supporting measure can effectively improve the deformation resistance of the support structure, reduce the pile diameter and reinforcement ratio of the support pile, facilitate the outward transportation of earthwork and protect the engineering pile. The finite element simulation calculation and measured data show that the horizontal displacement of the pillar pile is obviously restricted by the concealed bracing at the bottom of the pit, and the pile deformation and ground settlement meet the corresponding requirements. This research could provide reference for the application of similar foundation pit projects.