基于断裂力学的浅埋工作面过沟谷地形上坡段切顶机理分析  

Analysis on Fracture Mechanics Theory of Roof Cutting Mechanism of Shallow-Buried Working Face Crossing the Uphill Sections of Valley Terrains

作　　者：杨登峰[1] 李小双 马天辉[3] 谢生荣[4] YANG Dengfeng;LI Xiaoshuang;MA Tianhui;XIE Shengrong(College of Science,Qingdao University of Technology,Qingdao,Shandong 266520,China;School of Urban Construction,Changzhou University,Changzhou,Jiangsu 213164,China;State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian,Liaoning 116024,China;School of Energy and Mining Engineering,China University of Mining&Technology-Beijing,Beijing 100083,China)

机构地区：[1]青岛理工大学理学院,山东青岛市266520 [2]常州大学城市建设学院,江苏常州市213164 [3]大连理工大学海岸和近海工程国家重点实验室,辽宁大连市116024 [4]中国矿业大学(北京)能源与矿业学院,北京100083

出　　处：《矿业研究与开发》2024年第4期97-106,共10页Mining Research and Development

基　　金：国家自然科学基金项目(51704173);山东省重点研发计划项目(2019GSF111029);山东省深部冲击地压灾害评估工程实验室开放基金项目(LMYK2021007)。

摘　　要：浅埋煤层工作面推进至沟谷地形上坡段时,易出现关键层破断块体沿煤壁整体滑落失稳的大范围动载矿压灾害。根据沟谷上坡段顶板破断特征,基于断裂力学分析方法构建力学模型,探讨了顶板失稳的力学机理及基本顶破断失稳条件,获得了顶板来压步距及支架工作阻力的计算公式,并对各关键致灾因素进行了分析。研究结果表明:随着工作面推进,基本顶损伤区裂纹尖端的集中应力和应力强度因子增大,当应力强度因子增大到临界值时,悬臂梁破断工作面来压;沟谷坡角大小对来压步距及支架工作阻力起主要作用,损伤区裂纹长度、基本顶厚度、断裂韧性等因素也对其有较大影响;通过在麻地梁煤矿2103工作面进行现场监测,对理论分析结果进行了验证,进一步分析了支架阻力的合理值。研究工作提高了工作面过沟谷地形上坡段顶板控制的准确性,能够有效促进矿井的安全生产。When a shallow-buried coal seam working face is advanced to the uphill section of a valley terrain,it is prone to large-scale dynamic mining pressure disasters caused by the overall sliding and instability of key layer fracture blocks along the coal wall.According to the fracture characteristics of the roof in the uphill section of the valley terrain,a mechanical model was constructed based on the fracture mechanics analysis method,and the mechanical mechanism of roof instability and the basic roof fracture instability conditions were discussed.The calculation formulas for the roof weighting step and the working resistance of the support were obtained,and the key disaster causing factors were analyzed.The research results show that the concentrated stress and stress intensity factor at the crack tip of the basic roof in the damaged zone increase as the working face advances,and when the stress intensity factor increases to a critical value,the cantilever beam breaks and the working face is compressed.The size of the valley slope angle has a major impact on the weighting step and the working resistance of the support.Factors such as the crack length,the basic roof thickness,and fracture toughness in the damaged zone also have significant impacts.Through on-site monitoring at the 2103 working face of Madiliang Coal Mine,the theoretical analysis results were verified,and the reasonable value of support resistance was further analyzed.The research work has improved the accuracy of roof control of the working face crossing the uphill section of the valley terrain,which can effectively promote the safety production of the mine.

关 键 词：浅埋煤层 沟谷地形 上坡段 断裂力学 支架工作阻力 

分 类 号：TD323[矿业工程—矿井建设]