The strength reduction method (SRM) based on the generalized Hoek‒Brown (GHB) criterion has become an important and popular topic to analyse the stability of rock slopes. Various reduction strategies have been proposed and applied by the civil and mining engineering community. This paper proposed a new SRM for rock slopes with the GHB criterion based on the critical failure state curve (CFSC). The existence of the CFSC has been proven by theoretical analysis, and the explicit expression of the CFSCs for different parameters m_i and slope angles β, considering the influence of disturbance factor D, has been obtained by curve fitting based on a great deal of simulation data. The new SRM provides a graphic method to determine the parameters at the critical failure state from the initial state by reducing the compressive strength of intact rock σ_ci and the parameter combination s^α with the same ratio and proposes a definition of the factor of safety (FOS) based on the parameters of the two states. This method was applied to nine slope examples to verify its validity and accuracy. The relative errors between the critical state parameters obtained from the graphic method and that from the simulation analysis are less than 10%, which proves the accuracy of the CFSCs. The FOSs obtained by the proposed definition are compared with those obtained by the Bishop simplified method and the local linearization method (LLM), and the results are very close. The relative error is less than ± 5% compared with the LLM, and the stability state predicted is perfectly accurate. However, the calculation procedure is largely simplified, and the calculation speed is largely improved. A practical case of an open pit limestone slope with multiple steps was detailed analysed by the proposed SRM based on CFSC. The FOS results comparison with other existing method has demonstrated its feasibility and reliability in engineering application.

基于广义Hoek-Brown（GHB）准则的强度折减法（SRM）已成为分析岩质边坡稳定性的一个重要且热门的课题。土木和采矿工程界已经提出并应用了各种减少策略。本文提出了一种基于临界破坏状态曲线（CFSC）的 GHB 准则的岩石边坡新 SRM。通过理论分析证明了CFSC的存在，并在大量仿真的基础上进行曲线拟合，得到考虑扰动因子D影响的不同参数m _i和坡角β的CFSC的显式表达式数据。新的SRM提供了一种图解方法，通过降低完整岩石的抗压强度σ _ci和相同比例的参数组合s ^α来从初始状态确定临界破坏状态的参数，并提出了安全系数的定义（ FOS）基于两种状态的参数。将该方法应用到9个坡度算例中，验证了其有效性和准确性。图解法得到的临界状态参数与仿真分析的相对误差小于10%，证明了CFSCs的准确性。将所提出的定义得到的FOS与Bishop简化法和局部线性化法(LLM)得到的FOS进行了比较，结果非常接近。与LLM相比，相对误差小于±5%，预测的稳定状态非常准确。但计算过程大大简化，计算速度也大大提高。通过基于 CFSC 的 SRM 详细分析了一个多台阶露天石灰岩边坡的实际案例。FOS结果与其他现有方法的比较证明了其在工程应用中的可行性和可靠性。