白鹤滩水电站边坡结构面强度及稳定性分析

Study on Structural Surface Shear Strength and Stability of Baihetan Hydropower Station Slope

结构面变形及其破坏特征是岩体岩石力学研究的基本问题之一,针对白鹤滩水电站边坡工程,本文利用数值方法,研究了影响控制性结构面强度的一般性因素,确定了控制性结构面强度上限值;基于反演手段,获取了控制性结构面综合强度指标,并由此建立河谷演化模型再现河谷地应力场,根据结构面地应力赋存环境为选择合理的结构面本构模型奠定理论依据。在上述基础性研究前提下,利用平面数值计算手段分析了左岸边坡稳定性特征,并对平面计算结果进行了合理性评价;最后,基于岸坡改造、破坏过程中结构面性状弱化这一前提假设,利用强度折减法揭示了左岸边坡变形、破坏方式。解决了工程问题,并得到有关的方法应用认识。

The study on deformation, shear strength and failure mode of structural surface has been a concern in rock mechanics research of rock mass behaviors and engineering. Aiming at the key structural surface of left bank of Baihetan hydropower station rock slope, this paper has studied with several models common factors influencing its shear strength by the means of numerical analysis, and determined the upper limit for stability analysis. Based on back analysis method, the general shear strength of structural surface and the in - situ stress field of river valley have been obtained. From the basis of stress environment of key structural surface, a proper constitutive model is chosen for the slope stability analysis. Based on the above study, a series of numerical analysis have been carried out in order to find out the factor of stability of several geological sections and some argumentations on rationality of these plane a- nalysis results are put forward. Finally, according to the concept of structural surface＇ s weakness along with the pro- ceedings of slope reconstruction and failure t the mechanism of deformation and failure of left bank slope has been de- clared with the strength reduction method and the engineering problem has been solved.