不同JRC岩石节理剪切力学性质研究

摘要

以Barton提出的十条标准节理曲线为研究基础,利用离散元软件PFC建立岩石节理试样模型,在不同法向应力下进行直接剪切试验,研究粗糙度系数JRC与抗剪强度峰值的关系,以及不同JRC、不同法向应力条件下试样裂纹的扩展规律.结果表明:离散元节理剪切试验模拟结果与物理试验结果吻合较好.抗剪强度峰值随JRC和法向应力的增大而增大.试验过程中,裂纹产生在节理位置处,并主要集中在较大凸起处;裂纹数随着节理JRC的增加呈增多趋势,并且法向应力越大,裂纹数目线性增加.%Ten standard jointed curve proposed by Barton is taken as the research foundation with the model of rock joint generated and direct shear tests under different normal stresses conducted by PFC.Relationship between JRC and the peak shear strength along with development rules of cracks at different JRCs and normal stresses are studied.The results show that test results of simulated joints correspond well with that observed from physical tests.The peak shear strength increases with the increase of JRC and normal stress.Micro-cracks are produced in joint and concentrated in larger fluctuation.The number of crack number increased with the increase of joint JRC and crack number increases linearly with the change of normal stress.