考虑弱层置换的岩石边坡稳定性分析

锦屏一级水电站左岸边坡地质结构复杂，岩体存在大量深部裂隙、低波速松弛岩体、煌斑岩脉X及f2、f5断层，严重影响边坡的稳定性。采用基于强度折减法的岩石破裂过程分析RFPA方法对边坡典型部位在开挖后以及其对应弱层置换工况下的破坏全过程进行计算和分析，计算结果表明，f5断层在进行置换加固处理后，边坡安全系数较未置换弱层前提高了0.403，说明在岩质边坡开挖和支护前优先进行深部软弱结构置换处理，可以大大提高工程结构的安全储备。同时，RFPA强度折减法不仅能直观再现边坡潜在滑裂面从萌生到扩展直至贯通导致边坡整体失稳的全过程，而且可以得出边坡安全系数。研究结果对于边坡工程实施前稳定性评价和施工工序具有一定的参考价值。

Stability analysis of rock slope considering weak-layers replacement

The geological structures at left bank slope of Jinping First Stage Hydropower Station are very complicated. Many deep cracks and faults, such as f2, f5 and lamprophyres X, are the most significant factors that influence the stability of the rock slope. Based on the strength reduction method (SRM), realistic failure process analysis(RFPA) is used in the full failure processes evaluation of rock slope after excavation and its corresponding weak-layers replacement. From comparison results of numerical simulation, it can be observed that the safety factor increases by 0.430 after weak-layers replacement in deep rock mass, which illustrates the structural safety can be greatly improved if weak-layers replacement is conducted before excavation and support of rock slope. Furthermore, by using RFPA-SRM, not only the failure mechanisms and fracturing patterns, but also the safety factors can be obtained. The results can in turn be used for stability assessment and construction process determination of rock slope before construction.