为研究江漫滩特殊地质条件下悬挂式止水帷幕地铁深基坑施工引起的周边地表沉降规律，以7个江漫滩基坑工程的实测地表沉降数据为基础，采用理论分析、经验公式和有限元数值模拟的方法，总结了基坑开挖和坑内降水二者耦合作用引起的周边地表沉降变形规律。结果表明： 1）地表沉降范围可以划分为主要影响区、次要影响区和弱影响区3个区，主要影响区地表沉降主要由开挖和降水共同引起，次要影响区主要由降水引起。2）地表沉降曲线可根据划分的影响分区选用不同的函数表达式。3）基坑地表最大沉降点位置与坑边的距离xm为12.0～15.0 m，xm与基坑开挖深度h的比值约为0.7。4）在最大沉降点处，由开挖引起的地表沉降量占比为0.21~0.49，由降水引起的地表沉降量占比为0.51~0.79。

The surrounding ground surface settlement laws caused by coupling effect of foundation pit excavation and drainage are summarized based on settlement monitoring data from 4 foundation pits with suspended waterproof curtain in river floodplain by theoretical analysis, empirical formula and finite element numerical simulation method. The results show that: 1) The ground surface settlement can be divided into the main affected area, secondary affected area and weak affected area; the ground surface settlement of main affected area is mainly caused by foundation pit excavation and drainage; and the secondary affected area is mainly caused by drainage. 2) The ground surface settlement curve can be divided into different function expressions according to different affected areas. 3) The distance between the maximum settlement point of the foundation pit and the pit edge xm is 12.0-15.0 m; and the ratio of xm and the excavation depth of foundation pit is about 0.7. 4) The foundation pit excavationinduced ground surface settlement takes 35%; the drainageinduced ground surface settlement takes 65% at the maximum settlement point.