节理分布位置对岩体剪切破裂特征影响试验研究

节理分布位置影响岩体综合抗剪强度，并控制“锁固段”型岩质边坡启动和破裂演化。通过模型试件剪切试验，分析了节理分布位置对岩体综合抗剪强度和破裂特征的影响程度。试件模型以水泥砂浆为材料，在剪切面不同位置预制封闭节理，使其成为四周密封、内部节理贯通的模型。在不同法向应力下进行剪切试验，测定综合抗剪强度变化规律和剪切破裂特征。试验结果表明:试样破裂面可分为翼部拉张区、翼部压剪区、端部拉张区三部分，各区面积所占比例随节理位置变化而波动。剪切强度参数也随节理位置变化而规律性波动，且法向应力越大，变化幅度越大。

An experimental study of the influence of discontinuous structural planes at different locations on the shear fracture characteristics of rock mass

The joint distribution position has an effect on the comprehensive shear strength of rock mass and controls the initiation and fracture evolution of the locked segment type of a rock slope. The influence degree of the joint distribution on the comprehensive shear strength and fracture characteristics of rock mass is analyzed through model specimen making and shear tests. In the tests the cement mortar is taken as the model material, and the closed joint is prefabricated at different positions of the shear plane, making it a model with the sealing around and the internal joint through. The shear tests are carried out under different normal stresses to determine the variation law of shear strength and shear rupture characteristics. The test results show that the fracture surface of the sample can be divided into three parts: wing-tensile failure zone, wing compression-shear failure zone and end-tensile failure zone. The shear strength parameters also fluctuate regularly with the change in joint positions, and the greater the normal stress, the greater the variation range.