围岩强度和变形参数的分布特征及可靠性分析

从康家湾铅锌金矿Ⅲ-1号矿体上盘围岩取大量岩样，分别加工制作了50个压缩和拉伸试验的试样。利用RMT-150B伺服试验系统对试样进行单轴抗压、抗拉试验，各获得了50个试验结果。采用假设检验法，分别对50个单轴抗压强度和50个抗拉强度进行检验，结果表明，它们分别服从正态分布和对数正态分布；对50个 、 和50个C、 ，进行不放回抽样，组成50组E、 、C、 。利用FLAC计算软件，对硐室围岩中的应力进行了计算，分别获得了50个最大主应力和50个最小主应力；采用同样假设检验法，证明它们分别服从对数正态和正态分布；根据单轴抗压、抗拉强度及围岩中的最大主应力、最小主应力概率密度函数，计算了硐室围岩不发生拉伸破坏和压缩破坏的可靠度；并对硐室围岩抗剪强度的校核，得出了该地下硐室围岩稳定的结论。

Probability distribution of strength parameters and deformation parameters of surrounding rock and reliability analysis

Cores were taken from hanging wall of the Ⅲ-1 ore body at Kangjiawan Lead，Zink and Gold Mine. 50 samples for compression tests and 50 samples for tension tests were fabricated. And 50 compressive strength values and 50 tensile strength values were obtained by using the electro-hydraulic and servo-controlled testing system RMT-150B. The probability distributions for the compressive strength and tensile strength were tested by using the obtained compressive strength values and tensile strength values and the hypothesis test method. It is shown that the uniaxial compressive strength follows normal distribution; and uniaxial tensile strength follows the lognormal distribution. It composes of 50 groups of , , , by random sampling to 50 , and 50 , without replacement. The stress of surrounding rock was calculated by using FLAC and 50 maximum values and 50 minimum values were respectively gained. The results show the former follows lognormal distribution and the latter follows normal distribution. The reliability of surrounding rock without tensile and compression failure was calculated under uniaxial compressive, tensile strength and probability density function of maximum and minor principal stress. Shear strength and the stability of surrounding rock were checked.