坐标投影作图法在川藏线宿瓦卡岩质边坡稳定性分析中的应用

Coordinate projecting method and its application in the stability analysis of rock slope

边坡稳定性问题是川藏线工程建设面临的重要问题。野外调查发现基岩边坡失稳一般表现为块体塌落或滑动。基于岩体结构控制理论,作者以川藏线西藏境内宿瓦卡附近的人工高边坡为例,进行了块体边坡稳定性分析。对比现有理论方法的优缺点,采用坐标投影作图法及其计算机化程序CPH。坐标投影作图法是一种以正投影为基础,以分析岩体结构面的几何关系及由其切割出来的块体的稳定性为目的的图解方法。根据现场量测取得的数据,采用CPH程序确定了块体边坡的结构面方程,从而求出各结构面产状。在此基础上建立水平切面图,并求得各块体顶点坐标,计算出块体的表面积及体积。根据极限平衡理论,运用CPH程序进行块体稳定性分析,并求出块体的稳定性系数。通过分析可知,坐标投影作图法及其计算机化的CPH程序在块体边坡稳定性分析中有着很好的应用效果。

The stability of slope is an important problem in Sichuan - Tibet highway, and block falls and slides are often encountered in unstable slopes. The authors apply coordinate projecting method and its computerization program （CPH） to analyze the stability of the block slope in Suwaka along the highway. At first, CPH software is used to make up the equation and occurrences of structural planes. Secondly, horizontal sections are set up and coordinates of blocks＇ vertexes are obtained. At the same time, the surface areas and volumes of blocks are worked out. Finally, the authors analyze the stability of block. From the case study, it is indicated that coordinate projecting method and its computerization are effective in the stability analysis of block slope.