基于中厚板理论的顶板断裂失稳规律研究  

Study on the characteristics of roof fracture instability based on the theory of medium thick plate

作　　者：杨胜利[1,2,3] 岳豪 唐岳松 陈勇升 惠鼎恒 YANG Shengli;YUE Hao;TANG Yuesong;CHEN Yongsheng;HUI Dingheng(School of Energy and Mining Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;Engineering Research Center of Green and Intelligent Mining for Thick Coal Seam,Ministry of Education,Beijing 100083,China;Coal Industry Engineering Research Center of Top-Coal Caving Mining,Beijing 100083,China;The Norman B.Keevil Institute of Mining Engineering,University of British Columbia,Vancouver V6T 1Z4,Canada)

机构地区：[1]中国矿业大学(北京)能源与矿业学院,北京100083 [2]厚煤层绿色智能开采教育部工程研究中心,北京100083 [3]放顶煤开采煤炭行业工程研究中心,北京100083 [4]英属哥伦比亚大学NBK矿业工程学院,加拿大不列颠哥伦比亚省温哥华V6T 1Z4

出　　处：《岩石力学与工程学报》2024年第9期2092-2107,共16页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点研发计划(2022YFC2904001);国家自然科学基金资助项目(51934008,52121003)。

摘　　要：厚顶板工作面动载现象强烈,动载冲击作用下煤壁片帮、支架压架等现象常有发生。为了提升厚顶板条件下的采场围岩控制效果,以赵固二矿14030工作面为工程背景,采用理论分析、数值模拟和现场实测等方法,研究顶板变形与应力特征、破坏模式,探究动载效应及控制方法。结果表明:工作面初次来压时,最大拉应力和最大剪应力位于煤壁侧和开切眼侧中点,顶板发生拉伸破坏;周期来压时顶板在煤壁侧两端头形成了剪应力集中区,且剪切裂隙明显发育,顶板发生拉剪混合破坏。得到工作面推进距离与顶板厚度对拉(剪)应力的影响特征,分析顶板厚度效应对顶板破坏模式的影响。基于PFC3D建立顶板初次破断和周期破断数值模型,确定了顶板破坏形态、裂隙分布特征与破坏模式。基于砂体介入和厚度效应解释了顶板易发生剪切破坏的原因,揭示了顶板动载产生机制。利用动量守恒定理确定了顶板不同破断位置对采场造成的动载冲击力,得到液压支架受动载冲击影响的工作阻力,提出动载控制方法。研究结果可为中厚顶板或不满足薄板条件的顶板提供理论依据,指导中厚顶板工作面的安全生产。The working face of the thick roof is subject to strong dynamic loading,often resulting in coal rib spalling and hydraulic support crushing.In order to enhance the ground control under the thick roofs,the deformation and stress characteristics of the roof,failure modes,dynamic loading effects and control methods were investigated by taking the 14030 working face of the Zhaogu Second Coal Mine as the background.Based on the results from theoretical analysis,numerical simulation,and field measurement,it is found that the maximum tensile stress and maximum shear stress are located at the midpoint of the coal wall side and the cutting eye side during the first weighting,and the roof undergoes tensile failure.During periodic weighting,shear stress concentration zones form at both ends on the coal wall side,with significant development of shear cracks,resulting in mixed tensile-shear failure of the roof.The impact characteristics of the working face advance distance and the roof thickness on tensile(shear)stress were determined.The influence of roof thickness on failure mode was analyzed.Numerical models of first and periodic weighting of the roof were established using PFC3D,determining the roof failure morphology,crack distribution characteristics and failure modes.Based on the intervention of the sand and thickness effect,the reasons for the occurrence of shear failure in the roof were explained,revealing the mechanism of dynamic loading on the roof.By utilizing the principle of momentum conservation,the dynamic impact force caused by different fracture positions of the roof was calculated.The working resistance of the hydraulic support under dynamic load impact was obtained,and methods for dynamic load control were proposed.The research results can provide theoretical basis for medium-thick roofs or roofs that do not meet the conditions of thin plates,and help guide the safe production of medium-thick roof working faces.

关 键 词：采矿工程 中厚板 初次来压 周期来压 动载冲击 

分 类 号：TD[矿业工程]