基于Hoek-Brown准则的非等比强度折减方法

针对节理岩质边坡稳定性分析问题，开展了基于Hoek-Brown破坏准则的强度折减法研究。边坡的失稳过程是一个渐进累积破坏过程，破坏过程中各强度参数的衰减程度不同，在强度折减法中对应的折减系数也不同，不同折减系数间关系的确定及其综合安全系数的定义值得深入探讨。首先从岩体材料软化（硬化）特性出发，根据岩体强度参数从峰值强度到残余强度的变化规律，推导了Hoek-Brown破坏准则中3个强度参数折减系数间的数学关系式，然后以折减前后滑面上抗滑力之比定义综合安全系数来评价边坡的稳定性，最后结合算例验证了该方法的合理性，可有效应用于节理岩体边坡的稳定性分析。

Study of non-proportional strength reduction method based on Hoek-Brown failure criterion

For the stability analysis of jointed rock slopes, the strength reduction method based on the Hoek-Brown failure criterion is studied. Failure of slope is progressive. The attenuation degree of each strength parameter is different during the destroy process; so the reduction factors are different in the strength reduction method. Thus, the determination of the correlation between different reduction factors and the definition of the comprehensive safety factor is worthy of investigation. From the softening and hardening regularities of geomaterial perspective, the correlation between the three reduction factors in Hoek-Brown criterion is deduced in this article, based on the attenuation law of rock mass strength parameters from peak strength to residual strength. The slope stability can be evaluated with a comprehensive safety factor defined by the ratio of the anti-slide force on the sliding surface before and after reduction. Numerical simulation model is established based on the Hoek-Brown failure criterion; and the safety factor of slope is calculated using the strength reduction method. It is concluded that the calculated results based on Hoek-Brown failure criterion are similar to those calculated by other methods. The resemblance of their output validates the suggested method. The method proposed can be used in the jointed rock mass engineering, providing reference for the rock mass slope stability analysis.