基于地质力学模型试验综合法的顺层岩质高边坡稳定性研究

Stability of high bedding slope of rock based on comprehensive geo-mechanical model test

针对顺层岩质高边坡稳定性问题,提出降强法与倾斜抬升超载法相结合的地质力学模型综合的试验方法,推导该方法下边坡稳定综合法安全系数表达式,将其应用到白鹤滩左岸顺层岩质高边坡工程实例中,并与FLAC3D强度折减法数值计算结果进行对比。研究结果表明:2种方法得到的边坡变形破坏特征、破坏模式、安全系数均较为接近,说明所提的试验方法和安全系数表达式是合理的;白鹤滩左岸边坡的地质力学模型试验综合法安全系数KSC=1.526~1.575,数值计算得到的稳定安全系数KSS=1.45~1.52;边坡稳定安全的控制性结构面为层间错动带C3–1及其上盘岩体内的软弱结构面,层内错动带LS337上的加固措施是有效的。研究成果对顺层岩质高边坡安全稳定具有重要的工程意义和实用价值。

The geo-mechanical modelling experiment combining the reduction method with the overloading method by oblique lifting frame is proposed in order to investigate the stability of high bedding slope of rock. The expression of the comprehensive safety factor in the proposed method is deduced. This method is applied to the high bedding slope of rock on the left bank of Baihetan hydropower station and is compared with the result calculated from the numerical simulation with FLAC3D. The deformation characteristics, the failure mode and the safety factor of the slope calculated with two methods agree well. Therefore, the safety factor expression deduced in this paper is reasonable and the method proposed is feasible. The comprehensive safety factor Ksc= 1.526 - 1.575 from the test and the safety factor Kss = 1.45 - 1.52 from numerical calculation. The controlling factors of the slope are the bedding plane C3.1 and dipping weak structural surfaces above C3-1. The reinforcement measures taken on L5337 are effective.