Analysis of deep foundation pit enclosure construction and its surrounding settlement change

Abstract The paper takes the deep foundation pit project of Xiaoshan Qunxian Road West Extension Project as an example and analyses the problem of surrounding surface settlement caused by deep foundation pit excavation. The project foundation pit is about 30 meters deep, the surrounding environment is complex, and the settlement control requirements are strict. The study shows that soil stress release, groundwater change, deformation of supporting structures, and construction disturbance are the main factors leading to settlement. To effectively control settlement, the project has adopted multi-dimensional prevention and control measures such as a diaphragm wall plus an internal support system, layered precipitation and intelligent monitoring, and refined construction. The monitoring results show that the maximum settlement at the pit side is lower than the design limit, which verifies the effectiveness of the measures. Future research can further explore the application of soil improvement technology under complex geological conditions to enhance the settlement control capability of ultra-deep foundation pits.