论文部分内容阅读
利用颗粒流(PFC)构建了圆盘试样的巴西试验模型,模拟了含单条中心直裂隙和断续双裂隙试样的巴西试验,通过含中心直裂隙模拟结果与室内试验结果的对比,验证了细观参数的准确性和可靠性,并分析了裂隙参数对抗拉强度和裂纹扩展特征的影响.结果表明:抗拉强度总体随裂隙长度、岩桥倾角的增大而减小,随岩桥长度的增大而增大,但随裂隙倾角的改变呈非线性变化.断续双裂隙试样翼形裂纹一般萌生在裂隙的尖端,次生裂纹一般萌生在试样的边界.试样发生拉伸破坏,裂隙倾角主要影响翼形裂纹的萌生位置,岩桥倾角主要影响次生裂纹的萌生位置,裂隙长度主要影响试样的最终破裂程度,岩桥长度主要影响翼形裂纹的扩展程度.
A Brazilian test model of a disc sample was constructed by using particle flow (PFC). The Brazilian test was simulated with single-center straight crack and intermittent double-crack specimen. The comparison between the simulation results of the center-straight crack and the indoor test verifies The accuracy and reliability of the meso parameters are analyzed and the influence of the crack parameters on the tensile strength and crack propagation characteristics is analyzed.The results show that the tensile strength generally decreases with the increase of crack length and rock inclination, The length increases and increases, but it changes non-linearly with the change of crack dip angle.Fracture cracks occur in the crack tip and the secondary cracks generally occur on the sample boundary. Tensile failure and fissure angle mainly affect the location of wing crack initiation. Rock bridge inclination mainly affects the location of initiation of secondary cracks. The length of crack mainly affects the ultimate rupture of specimen. The length of rock bridge mainly affects the expansion of wing crack.