上海规范重力式围护墙稳定性若干问题探讨

重力式围护墙是软土地区常用的基坑支护形式，目前关于重力式围护墙的可靠度分析还不够完善，各因素对稳定性的影响机制等也存在一些疑问。以收集到的上海地区重力式围护墙实际工程为例进行可靠度分析，对水泥土重力式围护墙稳定性分析中的相关问题进行了探讨。分析结果表明，上海地区实际工程的设计安全水准通常高于规范规定值，其中水平滑动多为重力式围护工程稳定性验算的控制失效模式；通过提高插入比和墙体宽度可改善水泥土重力式围护基坑的抗倾覆、抗水平滑动稳定性的安全状态；对于整体稳定性，提高插入比较有效，墙体宽度的变化对其影响不敏感。

Discussion on stability of gravity retaining wall in Shanghai design code

Cement mixing gravity retaining wall is widely used as a supporting method in soft soil area. It is not clear enough about the reliability analysis of gravity retaining structures in Shanghai region, and doubts about the mechanism of various factors still exist. By analyzing some practical projects collected in Shanghai, this paper discusses some problems on both the reliability levels and stability of gravity retaining wall. The influences of some factors such as the insertion ratio, the excavation depth and the width of wall on its stability are also evaluated. The results show that the safety level of practical projects is usually higher than requirements in the design code. In these typical stabilities, the sliding stability is usually judged as the controlling mode of stability checking. The security status of sliding stability and overturning stability can be improved obviously when the width and insertion ratio of the gravity retaining wall. In addition, the increase of insertion ratio contributes much more than the increase of the wall width in improving the security status of overall stability.