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为考察含平行裂隙群岩体的强度特征及裂纹扩展规律,结合数字照相量测系统,对不同裂隙倾角下类岩石试样进行了单轴压缩试验。试验结果表明,受裂隙群的影响,试样的力学参数发生一定的劣化,峰值应力和弹性模量的劣化程度分别在10.84%~35.62%和9.79%~54.17%;随着裂隙倾角的逐渐增大,试样峰值应力呈现出先减小后增大的“U”型变化特征,?为45°时达到最小值。试样破裂形式与裂隙倾角?密切相关,?为15°和30°时,次生裂纹以倾斜裂纹和中部裂纹扩展为主,试样失稳破坏模式主要由倾斜裂纹主导;而?为45°、60°和75°时,次生裂纹主要为翼裂纹和共面裂纹,且试样失稳破裂模式主要取决于共面裂纹。
In order to investigate the strength characteristics and crack propagation law of rock masses with parallel fracture groups, the uniaxial compression tests of rock samples with different fracture dip angles were carried out in combination with digital photogrammetry system. The experimental results show that the mechanical parameters of the specimens are deteriorated to a certain extent under the influence of the fracture groups, and the degradation of peak stress and elastic modulus are 10.84% -35.62% and 9.79% -54.17%, respectively. With the gradual increase of fracture inclination Large, the peak stress of the sample shows a “U” type change characteristic which firstly decreases and then increases and reaches the minimum value at 45 °. The fracture mode of the specimen is closely related to the crack dip angle. At 15 ° and 30 °, the secondary cracks are dominated by the inclined crack and the central crack propagation. The failure mode of the specimen is mainly dominated by the inclined crack. , 60 ° and 75 °, the secondary cracks are mainly wing cracks and coplanar cracks, and the instability fracture mode of the specimens mainly depends on the coplanar cracks.