Hoek-Brown准则参数在边坡工程中的敏感性分析

Hoek-Brown屈服准则是估计完整岩石或节理岩体剪切强度的半经验准则，已成为岩体强度预测及稳定性分析领域应用最广泛的准则之一。选取常见的3类岩石材料作为分析代表，通过有限差分法及敏感性分析方法研究了Hoek-Brown准则中各参数对岩质边坡安全系数的灵敏度。研究表明，地质强度指标GSI对岩质边坡稳定性影响最为显著，而反映岩石的软硬程度材料常数mi、岩体扰动系数D和岩石单轴抗压强度?ci影响显著性要小于地质强度指标。最后，对GSI对岩体的摩擦角? 和凝聚力c的影响规律进行了分析。结果表明，对于同一GSI，mi从小到大变化时，? 的变化幅度在减小，GSI值在55附近时，不同mi所对应的凝聚力趋于同一个值。

Sensitivity analysis of Hoek-Brown failure criterion parameters on slope projects

As a semi-empirical rule for estimating shear strength of integral rock or jointed rock masses, the Hoek-Brown failure criterion has been one of the most useful criteria in forecast and stability analysis of rock masses strength. Three main kinds of rock materials are provided as the representative analysis; the sensitivity degrees of Hoek-Brown criterion parameters to the safety factor of rock slope are searched using the finite difference method and sensitivity analysis method. The research indicates that geological strength index(GSI) is the most sensitive to the rock slope stability, comparing to the material constant mi reflected the degree of rock soft and hard, the degree of disturbance to rock mass D and the rock uniaxial compressive strength ?ci. Finally, the influence rule of GSI to the rock masses angle of friction ? and cohesive strength c is analyzed. The result indicates that for the same GSI, the change scope is reducing for? while mi is changing from small to big and the cohesive strength tends to the identical value for different mi nearby GSI equal to 55.