“∞”型基坑地连墙支护结构受力特征分析与应用

Force Feature Analysis and Application of A Retaining Structure of "∞" Shape Foundation Pit

南京长江四桥南锚碇基坑平面形状为国内第一、国外罕见"∞"字形,无成功施工经验可供借鉴。施工前,设计人员通过有限元软件模拟施工过程中基坑地连墙支护结构在施工各工况下的变形和受力情况,初步得出该支护结构的受力变形特征。施工中,工程师根据监测要求选定监测内容,记录下各项监测数据,并进行整理,得出规律,进行总结。将前期正演计算结果和实际监测结果进行对比分析,得出该支护体系的受力和变形特征的一般规律,可供今后该类型基坑的设计施工参考。

The south anchorage foundation of the Fourth Nanjing Changjiang river Bridge is a ＂∞＂ plane shape.This kind of shape is the first in domestic and rare in world.There is not any successful construction experience to be learned.Before construction,the deformation of the retaining structure of the foundation pit was calculated by making proper hypothesis and calculation model.In the construction,the deformation data for the structure was monitored.The force and displacement feature of this kind of plane shape was finally analysed by comparing the forward calculation and monitoring data.The conclusion can give some experience to similar projects later.