圆形地下连续墙的变形分析

Distortion analysis of circular diaphragm walls

圆形基坑围护结构的工作性状不同于条形基坑,其围护结构与土体共同作用的空间效应及时变性非常明显。针对软土地基中圆形地下连续墙结构敏感性大的特点,利用有限差分元软件FLAC3D根据实际工程情况进行数值模拟分析,分别对基坑施工的不同工况和支护结构的应力分布情况进行了分析,当圆形地下连续墙发生整体倾斜时,地下续墙上局部应力加剧的现象明显。并从基坑稳定性、支护结构内力、土压力分布和结构敏感性方面对比现场实测结果,进行分析,所得结论为类似工程施工提供理论依据和参考。

The working status of the circular foundation pits is different from that of the rectangle foundation pits,because the time effect and spatial effect of the interaction between the excavation supporting and the soil are distinct.According to the sensitivity characteristics of circular diaphragm retaining walls,the FLAC^(3D) was employed to set up numerical modeling.The two distinct work conditions and the distribution stress of supporting structure were analyzed separately.It was found out that when the phenomena of the overall inclination occurred in the circular diaphragm walls,and the local stress aggravating of diaphragm walls was obvious.Compared with the data of local tests the foundation stability,internal force of supporting, distribution of earth pressure and structure sensitivity characteristics of diaphragm walls were analyzed.The conclusions provide theoretical basis and practical reference for the construction of similar projects.