针对基坑工程中渗流作用下基坑整体稳定性分析这一难点,在考虑基坑邻近水体水位变化及其非稳定渗流的基础上,同时考虑连续墙的影响,对常规边坡临界滑动场法进行改进,提出邻近水体多层地基深基坑整体稳定分析方法。以合肥地铁1号线大东门站基坑工程为依托,分析了邻近水体水位变化及其渗流作用下基坑开挖过程中整体稳定性变化,并与圆弧滑动法计算结果进行比较。结果表明:该方法可搜索出任意形状危险滑动面,相比于传统设计方法假定圆弧滑动面更合理,计算结果也更可靠;渗流作用是影响邻水基坑整体稳定性的主要因素之一,渗流场的变化会造成滑动面位置的改变。
Considering water level fluctuation, the transient seepage and the diaphragm wall, a method of analyzing the integral stability analysis of foundation pits under seepage was proposed based on the improved critical slip field of slope. Taking the foundation pit of Dadongmen station in metro line 1 of Hefei city as an example, the seepage analysis of the foundation pit with corresponding parameters was carried out and then the obtained pore-water pressure fields were imported into the program of the method to evaluate changes in the factor of safety with changing fiver water level and excavation depth. In addition, emphases were given to research the influence of seep- age on the integral stability of the foundation pit. The results showed that the method can search for the most dangerous slip surface of any shape and the safety factor is more reasonable than the traditional method in calculation of the integral pit stability. Moreover, the seepage have more influence on the integral stability of the foundation pit and the change of pore water pressure field can lead to change the position of slip surface.