基于Hoek-Brown准则的岩质边坡稳定性分析

 无论是传统极限平衡法还是数值模拟方法，强度准则和力学参数的选取对边坡稳定分析具有关键作用。基于非线性强度准则——Hoek-Brown强度准则，利用Slide软件，选取地质力学指标GSI、岩石材料参数mi、应力扰动系数D、边坡高度H及坡角b作为影响边坡稳定性的主要因素进行分析。分析结果表明：随地质力学指标GSI的增大，边坡稳定系数呈现出递增趋势，总体呈指数形式发展；GSI不同范围内，随着岩石材料参数mi的增大，边坡稳定系数F呈现出递增和递减2种截然不同的形式；随着应力扰动系数D的增加，稳定系数F呈直线形式递减；随着坡高H的增大，稳定系数逐渐减少，呈负指数形式发展。随坡角b的增大，稳定系数F逐渐减小，呈多段线形式发展，而b不同范围内斜率不同。根据E. Hoek等所提出的岩体分级标准中岩石单轴抗压强度界限值，对岩质边坡稳定系数进行分析，得到边坡稳定系数分布图。最后将稳定系数分布图应用于工程实例中，结果表明利用稳定系数分布图能很好地估算边坡稳定系数范围，与边坡稳定性定量分析结果具有较好的一致性。

ROCK SLOPE STABILITY ANALYSIS BASED ON HOEK-BROWN FAILURE CRITERION

The choice of the strength criterion and the mechanical factors is obviously important to the stability analysis of the slope，whether by traditional limit-equilibrium analysis or numerical simulation analysis. Based on the nonlinear strength criterion，Hoek-Brown strength criterion，the geology strength index GSI，the empirical constants of rock mi，the factor which depends upon the degree of disturbance to the rock mass，have been subjected to blast damage and stress relaxation D，and the height of slope H and the angel of slope are chosen as the main factors that control the stability of slope. The study of those factors has been carried out using a 2D slope stability program Slide. Conclusions can be drawn as follows：(1) with the increase of GSI value，the stability factor F shows increase trend in the form of exponent；(2) with the increase of mi value，F shows obviously different trends，increase or decline，in the different ranges of the GSI values；(3) with the increase of D value，F shows decline trend in the form of line；(4) with the increase of the height of slope H，F shows the decline trend in form of negative exponent；and with the increase of the slope angle ，F shows decrease in the form of polyline with different slopes，in the different ranges of . According to the limit value of the rock uniaxial compressive strength in the rock masses classification criterion which has put forward by E. Hoek et al，the stability of rock slopes is analyzed and the stability factor charts are drafted. Finally，the stability chart is used in a rock slope engineering，and the result shows that it can be used to estimate the range of the rock slope stability factor effectively and consistent to the quantitative analysis.