中文摘要：

以深圳平安金融中心基坑为研究背景,针对基坑围护结构特点,对其变形监测方案进行设计。结合基坑围护结构变形现场监测数据,重点分析基坑施工过程中围护结构的水平变形随基坑开挖深度和时间的变化规律、基坑开挖钢支撑轴力随时间的变化规律,结果表明基坑围护结构设计是安全的。同时,结合基坑地表沉降监测数据,分析基坑开挖引起的地表沉降变化规律,得出基坑开挖地表沉降可分为沉降量线性增长阶段、沉降速率不断增加阶段、沉降速率递减阶段以及沉降趋于稳定4个阶段。在此基础上,针对沉降变形的变化规律,引入Usher沉降预测模型,建立基坑开挖地表沉降预测模型。实测数据与预测值吻合较好,表明该方法的可行性。

英文摘要：

Taking the foundation pit of Ping＇an Financial Center in Shenzhen as background, deformation monitoring scheme is designed according to the characteristics of retaining structure of the foundation pit. The data of retaining structure deformation monitored at field are analyzed, focusing on the variation in horizontal deformation of the retaining structure with excavation depth of foundation pit and time, the change in axial force of steel support with time during the process of foundation pit excavation. The results show that the design is safe. According to the monitoring data of surface subsidence, the change in surface subsidence induced by the excavation of the foundation pit is analyzed. It is concluded that the surface subsidence can be divided into four stages, i.e. linearly increasing stage of settlement, continuous stage of settlement rate, declining stage of settlement rate, and approximately steady stage of settlement. Based on this, the Usher model for settlement prediction is introduced to establish the prediction model for surface subsidence. Measured data agree well with the predicted values, showing that the method is feasible.