类岩石材料裂纹单轴压缩扩展行为研究

构建可靠的裂隙网络模型是岩质边坡、隧道和地下矿山巷道等各类岩体工程稳定性研究的基础。开展室内试验，研究含不同尺寸、不同倾角裂纹岩样在单轴压缩下的力学行为。结果表明：类岩石试样的峰值强度随裂纹倾角的增大而减小，且随裂纹倾角的增大，峰值应力对应的应变减小、幅度较大，类岩石试样在峰值强度后，表现出准脆性破坏特点；裂纹尺寸对试样的峰值应力和对应的峰值应变有较大影响，随裂纹尺寸增大，试样的峰值应变增大，但裂纹的形状（圆形和矩形）对峰值应力、应变的影响较小；验证了最大周向应力理论得到的在不同裂纹倾角下的开裂角，与单轴压缩下到不同裂纹倾角进行比较，发现在裂纹倾角较小时裂纹的开裂角与试验得到的相差不大，约7.39%～11.82%；而裂纹倾角增大时，相差较大，约33.15%。

Study on Crack Propagation Behavior of Rock Materials under Uniaxial Compression

Building a reliable fracture network model is the basis for the research on the stability of various rock mass engineering such as rock slopes, tunnels and underground mine roadways. Laboratory experiments were carried out to study the mechanical behavior of rock samples with cracks of different sizes and inclination angles under uniaxial compression. The results show that: The peak strength of rock-like samples decreases with the increase of crack angle, and the strain corresponding to the peak stress decreases with the increase of crack angle, with large amplitude and the rock-like samples show quasi-brittle failure characteristics after the peak strength. The crack size has a great influence on the peak stress and corresponding peak strain of the sample. With the increase of the crack size, the peak strain of the sample increases. But the shapes of cracks(circular or rectangular shape) have little influence on the peak stress and strain. The crack angles obtained by the maximum circumferential stress theory under different crack dip angles were verified and compared with those obtained by uniaxial compression under different crack dip angles. It was found that the crack angles obtained by uniaxial compression under lower crack dip angles were approximately 7.39 %~11.82 %. When the crack angle increases, the difference is about 33.15 %.