基于矿物颗粒模型的裂隙煤岩微裂纹扩展演化规律研究  

Study on microcrack propagation and evolution of fractured coal-rock based on mineral particle model

作　　者：雷瑞德 粟罗 胡超 李俊 周林森 黄凌 顾清衡 LEI Ruide;SU Luo;HU Chao;LI Jun;ZHOU Linsen;HUANG Ling;GU Qingheng(College of Civil Engineering,Sichuan University of Science&Engineering,Zigong 643000,China;National and Local Joint Engineering Research Center of Shale Gas Exploration and Development,Chongqing Institute of Geology and Mineral Resources,Chongqing 401120,China;Engineering Laboratory for Safe and Precise Coal Mining of Anhui Province,Anhui University of Science and Technology,Huainan 232001,China)

机构地区：[1]四川轻化工大学土木工程学院,四川自贡643000 [2]重庆地质矿产研究院页岩气勘探开发国家地方联合工程研究中心,重庆401120 [3]安徽理工大学安徽省煤炭安全精准开采工程实验室,安徽淮南232001

出　　处：《煤矿安全》2024年第11期154-165,共12页Safety in Coal Mines

基　　金：四川省自然科学基金资助项目(2022NSFSC1033);重庆市博士后研究资助项目(2022CQBSHTB3109);安徽省煤炭安全精准开采工程实验室开放基金资助项目(ESCMP202305)。

摘　　要：为探究非均质性对裂隙煤岩变形局部化及微裂纹断裂失效机制的影响,基于构建的考虑矿物组分非均质结构细观模型,探究了裂隙煤岩变形破裂过程中应力场和位移矢量场演化特征,并量化了微观拉伸裂纹、拉剪裂纹和压剪裂纹的变化规律。研究表明:微观拉伸裂纹与拉-剪混合裂纹几乎同时萌生扩展,拉剪裂纹起裂较压剪裂纹早;剪切作用积聚区主要分布在裂隙尖端和岩桥区域,而拉伸作用积聚区主要分布在远离裂隙周围区域;随着岩桥角度增加,主导岩桥贯通破坏的裂纹由近似平行于轴向张拉混合破坏的间接贯通模式向剪切挤压破坏的直接贯通模式转变,另外,微观拉伸裂纹和剪切裂纹的萌生应力水平呈逐渐增加趋势。In order to explore the influence of heterogeneity on the deformation localization and the failure mechanism of fractured coal-rock,the characteristics of stress and displacement vector fields of fractured coal-rock during the deformation and fracturing process were investigated based on the constructed discrete element numerical model considering mineral components,and the evolution of micro-tensile cracks,tensile-shear mixed cracks and compressive shear cracks were quantitatively obtained.The results show that the initiation and expansion of tensile cracks and tensile-shear mixed cracks are almost simultaneous,and the tensile cracks initiate earlier than those of compressive-shear cracks.The accumulation area of compressive stress is mainly distributed around the fracture tip and rock bridge area,whereas the accumulation zones of tensile action are mainly distributed in the area far away from the pre-existing fracture.With the increase of the rock bridge angle,the crack leading the rock bridge through failure changes from the indirect through failure mode,which is approximately parallel to the axial tension mixed failure,to the direct through failure mode of shear and extrusion failure.In addition,the initiation stress levels of the micro tensile crack and shear crack show a gradual increase trend.

关 键 词：非均质性 矿物颗粒模型 裂隙煤岩 裂纹扩展 矢量场 

分 类 号：TD315[矿业工程—矿井建设]