三河尖关闭煤矿顶板砂岩三轴力学及渗透特性试验研究  

Experimental study on triaxial mechanics and permeability characteristics of sandstone on the roof of the closed Sanhejian Coal Mine

作　　者：张卫强[1,3] 潘梓良 张凤鸣 罗跃 陈尚斌[1,3] 朱术云[1] 吴云[1] 石章浩 金鑫[4] ZHANG Weiqiang;PAN Ziliang;ZHANG Fengming;LUO Yue;CHEN Shangbin;ZHU Shuyun;WU Yun;SHI Zhanghao;JIN Xin(School of Resources and Geosciences,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;The Fifth Geological Brigade of Jiangsu Geological Bureau,Xuzhou,Jiangsu 221004,China;Key Laboratory of Coalbed Methane Resources&Reservoir Formation Process,Ministry of Education,China University of Mining and Technology,Xuzhou,Jiangsu 221008,China;School of Mechanics and Civil Engineering,China University of Mining and Technology-Beijing,Beijing 100083,China)

机构地区：[1]中国矿业大学资源与地球科学学院,江苏徐州221116 [2]江苏省地质局第五地质大队,江苏徐州221004 [3]中国矿业大学煤层气资源与成藏过程教育部重点实验室,江苏徐州221008 [4]中国矿业大学(北京)力学与土木工程学院,北京100083

出　　处：《采矿与安全工程学报》2024年第6期1267-1278,共12页Journal of Mining & Safety Engineering

基　　金：江苏省自然资源保护利用专项资金(矿地融合试点)项目(苏财资环[2021]45号);矿区深部零碳负碳技术教育部工程研究中心开放基金项目(202309)。

摘　　要：针对三河尖关闭煤矿地下空间稳定性和封闭性问题,对其顶板砂岩试样开展三轴伺服渗透试验并同步开展声发射监测,研究不同围压下试样应力、应变、声发射和渗透率变化规律,分析渗透率与应力-应变和声发射的关联关系,在特征应力识别的基础上探究变形过程中岩石破裂类型和最终破坏模式。结果表明:随着围压增大,峰值强度、破坏应变、弹性模量和残余强度逐渐增大,围压由5 MPa增至15 MPa时,其增幅分别为68.17%,49.18%,17.26%和60.13%;空隙渗透率和破坏过程中的最大渗透率逐渐减小,但数量级未变;破坏时剪裂纹占比逐渐增大,破坏形态由单侧剪切破坏变为双侧剪切破坏。渗透率随应变的变化可分为略微下降、基本稳定、缓慢上升和快速上升4个阶段,缓慢上升阶段后出现数量级变化。裂纹体积法和渗透率取值法可对试样特征应力进行较好识别,但声发射受渗流作用的影响较大,无法对闭合应力和起裂应力进行有效识别。Considering the stability and closure of the underground space in the closed Sanhejian Coal Mine,triaxial servo permeability tests and acoustic emission monitoring were conducted on the sandstone samples from its roof.With the obtained test and monitoring results,the variations of stress,strain,acoustic emission,and permeability of samples under different confining pressures were studied,and how permeability was correlated with stress-strain and acoustic emission were analyzed.Based on characteristic stress identification,the rock fracture types and final failure modes during deformation were explored.The following beneficial results were obtained.As the confining pressure increases,the peak strength,failure strain,elastic modulus,and residual strength rise gradually.When the confining pressure changes from 5 MPa to 15 MPa,these four parameters rise by 68.17%,49.18%,17.26%,and 60.13%,respectively.The void permeability and the maximum permeability decrease progressively during failure,but their order of magnitude remains unchanged.The proportion of shear cracks grows gradually during failure,and the failure mode changes from unilateral shear failure to bilateral shear failure.The changes of permeability with strain can be divided into four stages,i.e.,slight decrease,basically stable,slow increase,and rapid increase,and the order of magnitude starts to change after the slow increase stage.The crack volume method and the permeability value method can effectively identify the characteristic stress of samples,while the acoustic emission method fails to effectively identify the closure stress and initiation stress as it is greatly affected by seepage.

关 键 词：关闭煤矿 顶板砂岩 围压 力学性质 渗透性 

分 类 号：TU45[建筑科学—岩土工程]