界面倾角对岩充组合体协同承载特征的影响机理  

The influence mechanism of interface dip angle on the synergistic bearing characteristics of rock-backfill composite

作　　者：冯国瑞[1,2,3,4] 王晶 杜献杰[1,2,3,5,6] 刘文昊 FENG Guorui;WANG Jing;DU Xianjie;LIU Wenhao(College of Mining Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;Shanxi Key Laboratory of Mine Rock Strata Control and Disaster Prevention,Taiyuan,Shanxi 030024,China;Shanxi-zheda Institute of Advanced Materials and Chemical Engineering,Taiyuan,Shanxi 030024,China;Shanxi Energy College,Jinzhong,Shanxi 030604,China;State Key Laboratory of Deep Geotechnical Mechanics and Underground Engineering,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;Zhengzhou Coal Industry(Group)Co.,Ltd.,Zhengzhou,Henan 450042,China;Shandong Shanke Digital Economy Research Institute Co.,Ltd.,Jinan,Shandong 250101,China)

机构地区：[1]太原理工大学矿业工程学院,山西太原030024 [2]矿山岩层控制及灾害防控山西省重点实验室,山西太原030024 [3]山西浙大新材料与化工研究院,山西太原030024 [4]山西能源学院,山西晋中030604 [5]中国矿业大学深部岩土力学与地下工程国家重点实验室,江苏徐州1221116 [6]郑州煤炭工业(集团)有限责任公司,河南郑州450042 [7]山东山科数字经济研究院有限公司,山东济南250101

出　　处：《中国矿业大学学报》2024年第6期1053-1062,共10页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(51925402);山西浙大新材料与化工研究院科研项目(2022SX-TD008);中国博士后科学基金面上资助项目(2022M712922)。

摘　　要：结构充填开采是为解决煤矿充填成本高、充填效率低等问题而提出的技术,其核心是形成充填体-直接顶协同承载结构,发挥直接顶的承载能力,降低充填率.为探究不同倾角对充填体-直接顶复合结构协同承载能力的影响机理,设计了0°~60°倾角岩充组合体的单轴压缩试验,通过声发射和数字图像相关技术监测组合体的受载破坏特征,并进行了界面力学分析.试验结果表明:组合体的强度和弹性模量随着倾角的增大有减小的趋势.小倾角组合体比大倾角组合体更容易实现协同承载与变形.岩充组合体最终的破坏呈现为3种形式,分别为协同贯穿型破坏、沿界面部分滑动破坏和沿界面整体滑动破坏.当岩层倾角小于30°时,界面压应力大于充填单体强度,组合体能够实现协同承载与破坏,声发射单个最大振铃计数出现在峰后阶段,一般由砂岩部分破坏或组合体块体脱落引起.当岩层倾角超过30°时,组合体存在界面抗剪切滑移阻力不足的问题,未能发生协同破坏,声发射单个最大振铃计数出现在峰前,组合体表观裂隙发育不明显.该研究对结构充填开采中充填体间隔布置时,不同岩层倾角条件下采空区“充填体-直接顶”协同承载结构的设计具有重要意义.Constructional backfill mining is a technology to solve the problems of high cost of backfill and relatively low efficiency of backfill,etc.The core of constructional backfill mining is form a synergistic bearing structure of backfill-direct roof,utilize the bearing capacity of the direct roof and reduce the backfilling rate.To explore the influence mechanism of different dip angles on the synergistic bearing capacity of backfill-direct roof composite structure,a uniaxial compressive stress experiment of rock-backfill composite with interface dip angle of 0°—60°were designed,and the failure characteristics of composite samples were tested using acoustic emission and digital image correlation,and the interfaces were mechanically analyzed.The results indicate that the strength and elastic modulus of the composite decrease with the increase of the interface dip angle.Strength synergies and deformation synergies are easier to achieve in low-interface dip angle composite samples than in high-interface dip angle composite samples.The final failure of the rock-backfill composite is presented in three forms,namely,synergistic penetration failure,partial interface cementation slip failure and overall sliding failure along the interface.When the dip angle of the rock stratum is less than 30°,the interface compressive stress is greater than the strength of the backfill,and the composite body achieves synergistic bearing and failure.The single largest ringing count of acoustic emission appears in the post-peak stage,which is generally caused by the failure of the siltstone or the detachment of the combination block.When the dip angle of the rock stratum exceeds 30°,the composite body has the problem of insufficient shear slip resistance at the interface,and the composite body does not achieve synergistic failure.The single largest ringing count of acoustic emission appears before the peak,and the apparent fissure development of the concentration is not obvious.This study is important to the design of backfill-direct ro

关 键 词：结构充填开采 岩充组合结构 界面倾角 协同承载 破坏特征 

分 类 号：TD823[矿业工程—煤矿开采]