摘要
再生顶板结构控制是回采工作面支护参数和支护方案设计的关键,再生岩体力学特性的确定是支护方案选择与支护参数设计的基础.采用RMT-150试验机开展胶结再生岩体单轴压缩试验,结合SEM电镜扫描系统研究不同胶结介质条件下再生岩体的强度特性及固结机理.研究结果表明:水灰比和胶结介质是影响强度的主要因素,在单轴压缩测试试验结果中,超细水泥试样最高强度为12.5 MPa,普通水泥最高强度为10.2 MPa,石膏最高强度为6.7 MPa;水灰比为5∶10,6∶10,7∶10时,胶结质固结体强度随水灰比的增大而减小,胶结再生岩体强度随水灰比的提高呈现逐渐增大,再逐渐减小的趋势;电镜扫描试验分析胶结介质的胶结特征和岩-浆交界面孔隙形态,从微观角度确定岩-浆界面孔隙特征,胶结特征由包裹式接触到依附式接触是降低强度的主要因素.通过对不同水灰比条件下不同胶结再生岩体强度的影响因素进行分析,为破碎条件下再生顶板支护研究提供参考依据.
The control of regenerated roof structure is the key to the support parameters and scheme design of the mining face.The determination of the mechanical properties of the regenerated rock mass is the basis for the selection of the support scheme and the design of the support parameters.The uniaxial compression test of cemented regenerated rock mass is carried out with RMT-150 testing machine,and the strength characteristics and consolidation mechanism of the regenerated rock mass under different cementation media are studied with SEM scanning system.Results show that the water cement ratio and the cementation medium are the influencing factors of the strength.In the uniaxial compression test results,the maximum strength of the ultra-fine cement sample is 12.5 MPa,that of the ordinary cement is 10.2 MPa,and that of the gypsum is 6.7 MPa.In the range of water cement ratio 5∶10,6∶10,7∶10,the strength of cemented solid decreases with increasing water cement ratio and the strength of cementitious regenerated rock mass gradually increases with the increase of water cement ratio,and then slowly increases.The electron microscope scanning test analyzes the cementation characteristics of the cementation medium and the pore morphology of the rock slurry interface,and determines the increase of the pore number of the rock slurry interface from the microscopic perspective.The cementation characteristics from the wrapped contact to the attached contact are the main factors to reduce the strength.By analyzing the influencing factors of the strength of different cemented regenerated rock mass under different water cement ratio,it provides references for the research on the support of regenerated roof under broken conditions.
作者
吴欢
王平
丁理
江永志
曾梓龙
喻迪
WU Huan;WANG Ping;DING Li;JIANG Yongzhi;ZENG Zilong;YU Di(School of Resources,Environment and Safety Engineering,Hunan University of Science and Technology,Xiangtan 411201,China;Key Laboratory of Disaster Prevention and Control of Coal Mine Gas and Roof Plate in Southern China,Hunan University of Science and Technology,Xiangtan 411201,China;Hunan Provincial Key Laboratory of Safe Mining Techniques of Coal Mines,Hunan University of Science and Technology,Xiangtan 411201,China)
出处
《矿业工程研究》
2023年第4期1-9,共9页
Mineral Engineering Research
基金
国家自然科学基金面上资助项目(52174110)
湖南省教育厅重点资助项目(21A0313)
煤矿安全高效开采省部共建教育部重点实验室一般资助项目(JYBSYS2021203)
湖南省自然科学基金青年项目(2020JJ5186)。
关键词
再生岩体
力学特性
胶结介质
水灰比
cemented regenerated rock mass
mechanical properties
cementitious substance
water cement ratio
