结构面抗剪强度参数线性拟合方法适用性研究

针对岩体结构面力学参数的重要性，开展最小二乘法、点群中心法、随机-模糊法、可靠度分析法4种结构面抗剪强度参数线性回归方法的理论对比与分析。在传统点群中心法的基础上，提出求解过程严密、计算精度较高的改进优化算法。为保证可靠度分析法中验算点法参数初始赋值的准确性，提出基于可靠度理论的结构面抗剪强度参数c， 的均值、标准差优化赋值方法。以武隆县鸡尾山滑坡为例，比较不同岩体结构面数据条件下上述4种方法的适用性。结果表明，各方法的适用性与试验数据的离散性及数据量有关；当数据线性理想时，4种方法均可直接用于结构面抗剪强度参数的线性回归分析；当试验数据较离散时，点群中心法已不再适用，可根据工程要求、异常值情况和计算收敛情况选取合适的数据处理方法。

Applicability study of linear fitting method of shear strength parameters of rock mass discontinuities

Due to the importance of study of mechanical parameters of rock mass discontinuities, four shear strength parameters linear regression methods, i.e. least square method, point center method, random-fuzzy method and reliability method, were carried out to conduct the comparison and theoretical analysis. An improved algorithm with rigorous solving process and higher calculation accuracy was proposed based on the traditional point center method. The optimized mean and standard deviation assignment method of shear strength parameters c, of rock mass discontinuities was presented to ensure the accuracy of initial assigned parameter with JC method based on reliability theory. An example of Jiweishan landslide in Wulong County was taken to explain the applicability of the above four methods under different data conditions of rock discontinuities. The result indicates that the applicability of four methods depends on the divergence and volume of the data. Each method of the four can be directly applied for the linear regression analysis of the shear strength parameters of rock discontinuities when the data is under good linear relationship. However, the point center method is not available anymore when the data is discrete; and the reasonable method should be determined according to the engineering requirements, exceptional value and convergence conditions.