基于离散元方法的预制裂纹扩展过程分析

对预制裂纹花岗岩试件进行了单轴压缩试验，得出了不同裂纹倾角下的岩石强度与弹性模量变化规律.建立了不同裂纹倾角下的岩石颗粒流计算模型，并根据室内试验结果标定了计算模型的细观参数.通过编制FISH语言提取了裂纹扩展过程中的裂纹信息，并进行了详细分析.研究结果表明:随着预制裂纹倾角的增大，裂纹起裂应力、起裂角不断增大，裂纹扩展由最初的翼型裂纹占主导向次生裂纹占主导转变;通过定义的裂纹聚集系数分析得出随着裂纹倾角的增大，裂纹聚集系数曲线由光滑变得曲折，裂纹扩展路径由集中向分散过渡.

Analysis of Pre-existing Crack Propagation Process Based on Discrete Element Method

Uniaxial compression experiments were carried out for granite specimen with pre-existing cracks. Variation laws of rock strength and elastic modulus under different crack angles were obtained， and the crack propagation process was recorded. The calculation model for rock particle flow under different flaw inclinations was established and the micro-parameters of calculation model were calibrated based on the laboratory testing results. Crack information during the crack propagation process was extracted by FISH language and was also analyzed in detail. The results show that with the increase of crack inclination， both the crack initiation stress and initiation angle increase continuously. The crack propagation types change from wing-crack-dominated to secondary-crack-dominated. Through the analysis of crack aggregation coefficient， it is found that with the increase of crack angle， the curve of crack aggregation coefficient changes from smooth to tortuous， and the crack propagation path is under the transition from concentrated to decentralized.