A comprehensive understanding of deformation characteristics and control measures for large-scale foundation pits in soft soil regions is of increasing importance to their risk assessment, design, and construction. In this study, the influences of the thickness of soft soil on the deformation of foundation pits are discussed based on statistical data from 24 foundation pits in floodplain areas of Nanjing, China. The mean maximum ground surface settlement around the pit in floodplain areas of Nanjing was 0.38%H, and the maximum ground surface settlement was observed at 0.48H. The maximum influence scope of ground surface settlement was about 3.5H, and the average maximum horizontal displacement of supporting structures was 0.23%H. On this basis, a model of ground surface settlement around the pit according to excavation depth for foundation pits in floodplain areas is derived. In addition, the influence scope around the pit and relevant control measures are proposed for the protection of surrounding underground structures and roads.

全面了解软土地区大型基坑的变形特征和控制措施，对于其风险评估，设计和施工越来越重要。本研究基于南京洪泛区24个基坑的统计数据，探讨了软土厚度对基坑变形的影响。围绕南京漫滩地区坑的平均最大地面沉降为0.38％^ h，在0.48为观察到最大地表沉降^ h。地表沉降的最大影响范围约为3.5 H，支撑结构的平均最大水平位移为0.23％H。在此基础上，推导了洪泛区基坑开挖深度下基坑周围地表沉降的模型。此外，为保护周围的地下结构和道路，提出了坑周围的影响范围和相关的控制措施。