炭质页岩力学特性各向异性及其破坏机制研究  

Study on failure mechanism and mechanical properties anisotropy of carbonaceous shale

作　　者：曹洋兵[1,2] 陈杨涛 张遂 李新卫[3] 沈红钱[3] CAO Yangbing;CHEN Yangtao;ZHANG Sui;LI Xinwei;SHEN Hongqian(College of Environmental and Resources,Fuzhou University,Fuzhou,Fujian 350108,China;Key Laboratory of Ministry of Land and Resources on Geohazard Prevention of Hilly Mountains(Fujian Provincial Key Laboratory of Geohazard Prevention),Fuzhou,Fujian 350108,China;103 Geological Brigade of the Bureau of Geology and Mineral Exploration and Development in Guizhou Province,Tongren,Guizhou 554300,China)

机构地区：[1]福州大学环境与资源学院,福建福州350108 [2]国土资源部丘陵山地地质灾害防治重点实验室(福建省地质灾害重点实验室),福建福州350108 [3]贵州省地质矿产勘查开发局一〇三地质大队,贵州铜仁554300

出　　处：《福州大学学报（自然科学版）》2020年第2期244-250,共7页Journal of Fuzhou University(Natural Science Edition)

基　　金：贵州省科技计划项目(黔科合[2016]支撑2902,黔科合平台人才[2018]5618号,黔科合支撑[2019]2868号);国土资源部丘陵山地地质灾害防治重点实验室(福建省地质灾害重点实验室)开放基金资助项目(FJKLGH2017K004,FJKLGH2017K002);自然资源部基岩区矿产资源勘查工程技术创新中心联合资助。

摘　　要：以贵州松桃李家湾锰矿矿体顶板炭质页岩为研究对象,开展页理面与加载方向不同夹角条件下纵波波速、单轴压缩及电镜扫描等试验,并以最大值与最小值的比值定义各参量的各向异性系数.结果表明:①纵波波速随入射方向与页理面夹角α增大而减小,其各向异性系数R v为1.44;弹性模量随加载方向与页理面夹角β增大而减小,其各向异性系数R E为1.14;单轴抗压强度σucs呈现出两头大中间小的“U”型特征,最小值在β为37°时取得,其各向异性系数Rσ为3.01.②不同β条件下,单轴压缩应力-应变曲线有起始压密和弹性压缩阶段,都具有明显的应变软化特征.③单轴压缩下,炭质页岩在β=0°时主要为拉破坏,页理面抗拉强度和基质体弯折拉断强度协同控制其力学特性;在β=32°时主要为沿页理面剪破坏,页理面抗剪强度控制其力学特性;在β=66°时主要为沿页理面和切断基质体的剪破坏,页理面和基质体的抗剪强度协同控制其力学特性;在β=90°时主要为拉破坏并含有少量沿页理面剪破坏,页理面抗剪强度和基质体抗拉强度协同控制其力学特性.The carbonaceous shale on the roof of the Lijiawan manganese ore body in Songtao, Guizhou Province, was taken as the study object. P-wave velocity test, uniaxial compression test and scanning electron microscopy test were carried out at different angles between the shale plane and the loading direction. The anisotropic coefficient of the parameters was defined by the ratio of the maximum value to the minimum value. The results show: ① P-wave velocity decreases with the increase of angle α between the incident direction and the shale plane, and its anisotropy coefficient Rv is 1.44. The elastic modulus decreases with the increase of the angle β between the loading direction and the shale plane, and its anisotropy coefficient RE is 1.14. The uniaxial compressive strength σucs presents a "U" shape characteristic with the middle value is small and the values on both sides are large. The minimum value of the σucs is obtained at β equals to 37° and its anisotropic coefficient Rσ is 3.01. ② Under different β conditions, the uniaxial compression stress-strain curve has initial compression and elastic compression stages, and have obvious strain softening characteristics. ③ Under uniaxial compression, carbonaceous shale is mainly tensile failure at β=0°, and the tensile strength of the shale plane and the bending and breaking strength of the matrix body control the mechanical properties. When β = 32°,the shearing damage is mainly along the shale plane,and the shear strength of the shale plane controls its mechanical properties. When β = 66°,it is mainly the shear failure along the shale plane and cutting matrix body,and the shear strength of the shale plane and the matrix body synergistically control the mechanical properties. When β = 90°,it is mainly tensile failure and contains a small amount of shearing along the shale plane. The shear strength of the shale plane and the tensile strength of the matrix body control the mechanical properties.

关 键 词：锰矿开采 炭质页岩 力学特性 各向异性 破坏机制 

分 类 号：TU45[建筑科学—岩土工程]