黄土边坡稳定性的简单判别方法——以兰州地区阶地黄土边坡为例

Simple Method for Judging the Stability of Loess Slope: Terrace Loess Slope in Lanzhou Area as an Example

边坡稳定是土木工程中十分重要的问题,黄土边坡稳定性具有明显的地域特点.从兰州地区二三四级阶地取原状黄土,测试黄土的颗粒成分、水溶盐含量、碳酸钙含量、有机质含量、内摩擦角和粘聚力;从黄土的物理性质和力学性质得出高阶地边坡稳定性高于低阶地边坡.以地貌特征、阶地类型、物理性质及力学性质为指标,结合边坡稳定状况调查成果,将黄土边坡划分为不稳定、稳定和极稳定3类.此分类一方面反映边坡的工程地质特性,另一方面可快速定性判别边坡稳定性.

Slope stability is a very important issue in civil engineering;it is especially true of loess slope for its specific regional characteristics. Intact loess was drawn sample from the second, third and fourth terrace in Lanzhou area and the samples were tested in terms of their physical characteristics, such as grain composition, the content of water soluble salt and calcium carbonate and organic compounds. In addition, mechanical properties of c and ~p were also examined. The results of the present study show that loess slopes in high terrace are more stable than those of low terrace. According to geomorphologic features, terrace types, physical characteristics, mechanical properties of undisturbed loess, and the results of the slope stability examination, loess slope stability is divided into three kinds： unstable, stable and extremely stable. This classification, on one hand, reflects the engineering geological characteristics of slopes;on the other hand,it helps judge the loess slope stability quickly.