ZHANG Wen-lian, SUN Xiao-yun, CHEN Yong, et al. Slope stability analysis method based on compressive
strength reduction of rock mass[J]. 2022, 43(S2): 607-615.
ZHANG Wen-lian, SUN Xiao-yun, CHEN Yong, et al. Slope stability analysis method based on compressive
strength reduction of rock mass[J]. 2022, 43(S2): 607-615.DOI: 10.16285/j.rsm.2021.0170.
在岩体边坡稳定性分析方法中,基于非线性Hoek-Brown准则的强度折减法,存在折减方案不统一或计算太复杂等问题。针对这一问题,提出了一种基于岩体抗压强度的广义Hoek-Brown准则强度折减法,比直接折减材料参数,更能体现强度衰减的物理意义。方案以岩体单轴抗压强度作为折减依据,对岩石单轴抗压强度sci和反映岩体结构特征的参数组合sa(s、a 均为模型参数)进行同比折减,分析该方案下抗剪切强度和抗拉强度的折减比例,并基于平均抗剪强度定义安全系数。应用该方案,对两个经典边坡算例进行稳定性分析,将所得安全系数、临界滑动面与局部线性化强度折减法、极限平衡法进行对比。结果表明,对于两算例,本方法所得安全系数与其他两种方法结果接近,相对误差低于2%;在算例1中,本方法得到的临界滑动面位置与其他两种方法结果一致性很高;在算例2中,本方案滑动面位置更接近于局部线性化法,且能同时反映剪切和拉伸破坏。以上结果验证了本强度折减方案和安全系数定义法的可靠性和合理性。In the rockslope stability analysis methods
the strength reduction method based onnonlinear Hoek-Brown criterion has some problems
such as the disunity ofreduction schemes or the complexity of calculation. To solve this problem
ageneralized Hoek-Brown criterion strength reduction method based on thecompressive strength of rock mass is developed
which can better reflect thephysical significance of strength attenuation than the direct reduction ofmaterial parameters. Based on the uniaxial compressive strength of rock mass
the uniaxial compressive strength of intact rock sci and the parameters’ combination sa (s and a are empirical parameters ofrock mass) are reduced by thesame ratio
the reduction ratios of shear strength and the tensile strength areanalyzed
and the factor of safety is defined based on the average shearstrength. The proposed method is applied to the stability analysis of twoclassical slope examples
and the factor of safety and critical sliding surfaceobtained are compared with the local linearized strength reduction method andthe limit equilibrium method. The results show that the factor of safety obtainedby the proposed method is close to that obtained by the other two methods fortwo examples
and the relative error is less than 2%. In example 1
thelocation of the critical sliding surface obtained by the proposed method is ingood agreement with the results of the other two methods. In example 2
thecritical sliding surface of the proposed method is closer to that of the locallinearization method
and can reflect both shear and tensile failures. Theabove results verify the reliability and rationality of the proposed strengthreduction scheme and the definition method for factor of safety.