摘要
针对大倾角厚煤层走向长壁分层开采再生顶板稳定性控制工程难题,结合淮南潘北煤矿1212(3)厚煤层分层工作面地质与工程条件,综合运用矸石侧限压缩试验、三维成像钻孔探测试验以及物理模拟与数值模拟等研究方法,分析了含水率、压缩率和粒径级配等因素对矸石压缩特性的作用机理及其对再生顶板稳定性影响程度的关联特征,获得了再生顶板结构特征与应力状态,揭示了再生顶板采动力学行为,制定了再生顶板稳定性控制措施,评价了再生顶板稳定性控制效果。研究结果表明:采空区泥岩与砂质泥岩黏土矿物含量高,利于矸石二次胶结;矸石受载压缩过程中的接触状态与应力状态不断调整,表现为再生顶板结构垂向上,下部与上部矸石压缩胶结程度均高于中部,倾向上,中上部矸石压缩胶结程度最小,再生顶板更易破坏;矸石粒径级配是影响再生顶板抗剪强度的主要因素,随矸石粒径增大,再生顶板表现出沿剪切线滑移到矸石颗粒错动鼓出的延性破坏,即再生顶板倾向下部采动破断剧烈程度较中上部缓和,中上部是再生顶板稳定性控制的重点防控区;主应力偏转驱动下分层采场空间不同区域再生顶板破断,提出再生顶板冒顶和煤壁片帮注浆与架棚加固方案,通过监测煤壁片帮深度与支架压力,再生顶板稳定性控制效果良好。
This study focused on the stability control of roof in long wall stratified mining of large dip angle thick coal seam.Taking Panbei Coal Mine in Huainan as an example,the effect mechanism of water content,compression ratio and grain size grading on the compression characteristics of gangue is analyzed by comprehensive application of gangue lateral compression test,3D imaging borehole detection test,physical simulation and numerical simulation method.In addition,the effect of these factors on the stability of the reclaimed roof were also analyzed,the structural characteristics and stress state of the reclaimed roof were obtained,the dynamic behavior of the reclaimed roof was revealed,the stability control measures of the reclaimed roof were formulated,and the control effect of the reclaimed roof stability was evaluated.The research results indicate that the clay minerals of goaf mudstone and sandy mudstone are beneficial for the secondary cementation of gangue.The contact state and stress state of the gangue during compression under load are constantly adjusted,manifested as the compression and bonding degree of the lower and upper gangue being higher than that of the middle,with the compression and bonding degree of the middle and upper gangue being the smallest,and the regenerated roof being more prone to damage.The particle size distribution of gangue is the main factor affecting the shear strength of recycled roof.As the particle size of the gangue increases,the regenerated roof exhibits ductile failure that slides along the shear line to the staggered and bulging of the gangue particles.That is,the degree of mining fracture in the lower part of the regenerated roof tends to be milder than in the middle and upper parts,and the middle and upper parts are the key prevention and control areas for the stability control of the regenerated roof.The deflection of the main stress can lead to the fracture of the regenerated roof,so a plan for the collapse of the regenerated roof and the grouting.
作者
池小楼
杨科
付强
张寨男
CHI Xiaolou;YANG Ke;FU Qiang;ZHANG Zhainan(School of Mining Engineering,Anhui University of Science and Technology,Huainan 232001,China;State Key Laboratory of Mining Response and Disaster Prevetion and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China)
出处
《煤炭科学技术》
EI
CAS
CSCD
北大核心
2023年第6期1-10,共10页
Coal Science and Technology
基金
中国博士后科学基金面上资助项目(2022M721296)
安徽理工大学高层次引进人才科研启动基金资助项目(2021yjrc10)。
关键词
大倾角厚煤层
重复采动
再生顶板
分层开采
围岩控制
steeply dipping thick coal seam
repeated mining
regenerated roof
stratified mining
surrounding rock control
