裂隙岩体结构面直剪特性与参数反演试验

Back analysis test on mechanical property and parameters of structure surface to direct shear in fracture rock mass

为准确获取裂隙岩体工程中结构面的力学参数,以细观岩石力学理论和岩石结构面的数字精细化测量为基础,运用PFC^(2D)颗粒流软件,建立铜坑矿锌铜矿体裂隙结构面的精细数值仿真模型,开展节理岩石直剪数值模拟试验。实现岩体结构面的剪切力学参数的反演与预测,获得铜坑矿裂隙节理结构面的抗剪力学参数。研究结果表明:由于结构面平滑,在裂隙结构面的直剪数值模拟试验过程中,主要形成剪切滑移破坏;铜坑矿裂隙结构面的黏聚力为0.45 MPa,内摩擦角为35.8°,其反演的数值计算结果与本地区高峰矿的无厚度节理面试验数据相似度高,试验结果可为岩体结构面参数的工程应用提供基础参数。

Based on the microscopic rock mechanics and the digital detailed measure of morphology characteristicsin the joint surface,the numerical model was built to simulate the direct shear test of the fracture rock surface in theTongkeng zinc/copper mine.The parameters of joint were back analyzed by the software PFC2D(particle flow code).The mechanical parameters of the rock mass structure were obtained and predicted by back analysis method fromthe numerical shear test.Numerical simulation results showed:The main failure is the interfacial shear slip underthe smooth joint surface;The cohesion of the structure surface is0.45MPa,and the internal friction angle is35.8°in Tongkeng zinc/copper mine;it is consistent between the simulated results and the results of the Gaofeng Mine.