摘要
针对底分层煤层开采诱导采场再生顶板二次破坏和支架失稳特点,以潘北矿1212(3)再生顶板下大倾角煤层工作面为例,综合运用井下钻孔三维成像对再生顶板结构实测、基于声发射监测技术的相似物理模拟和理论分析3种技术手段,对大倾角煤层综采面再生顶板顶板结构、垮落特征以及支架失稳模式进行了研究。通过对底分层再生顶板施工的3个钻孔进行孔壁成像确定了底分层再生顶板胶结压实状态,结合相似物理模拟确定了煤层回采过程中的再生顶板垮落规律,并采用理论计算分析了再生顶板运动对采场支架稳定性的影响程度。结果表明:①受煤层倾角影响,再生顶板压实程度呈现出采场下部高于采场中部,采场上部压实程度最弱的非对称压实特征;②底分层顶板3~5 m范围内岩层易在支架间冒漏,此范围再生顶板是改变支架位态的关键岩层;③底分层再生顶板破断失稳经历了6个阶段,基于声发射信号强弱程度确定了采场下部再生顶板高位悬臂梁的断裂和上部再生顶板的滑移是引起底分层顶板破碎严重的主因;④基于现场支架载荷数据,验证了相似物理模拟准确性,标划出采场上部是支架稳定性重点防控区域;⑤在综合厘定再生顶板-支架作用关系基础上,构建再生顶板运动下的大倾角煤层采场支架倾倒和下滑失稳模型,分析支架受力特征,获得支架在倾倒、下滑临界状态下的架间作用力分别为-126.8 kN,86.2 kN,揭示了再生顶板载荷作用位置对支架稳定性影响显著;⑥探讨了护帮、护顶和护架的三位一体协同支护体系。
Based on the characteristics of the steeply dipping 1212(3)working face with the cataclastic regenerative roof of Panbei mine,the characteristics of secondary failure of surrounding rock and instability of support caused by coal seam mining have been discussed.The three-dimensional borehole imaging,similar simulation with acoustic emission and theoretical analysis have been used to study the structure and caving characteristics of roof and the support instability model of fully mechanized mining face with steeply dipping seam.The consolidation and compaction state of cataclastic regenerative roof were described by the image of three boreholes.Then,similar simulation with acoustic emission and theoretical analysis method were used to explore the characteristics of the roof caving and sliding and the mechanism of support instability.The study shows that:①affected by inclination angle,the characteristics of the compaction degree of cataclastic regenerated roof was that the lower part of the stope was higher than the middle part’s and the upper part of the stope with the weakest compaction degree.②In the range of 3-5 m of cataclastic regenerated roof which was the key layer to change the position and state of support was easy to leak between the supports.③The breaking of cataclastic regenerated roof had experienced six stages.Based on the strength of acoustic emission signal,the main causes of the fracture and instability of the cataclastic regenerated roof were the fracture of the upper cantilever beam and the slip of the cataclastic regenerated roof.④The upper part of stope was marked as the key prevention and control area of support stability,based on the field support load data which had verified the accuracy of similar physical simulation.⑤Based on the comprehensive analysis of the relationship between cataclastic regenerated roof and the support,the dumping and sliding instability models of steeply dipping stope under the cataclastic regenerated roof was constructed.The force characteristics of the support were analyzed and the inter-forces of the support under the critical state of tipping and sliding were-126.8 kN and 86.2 kN,respectively,which revealed that the position of cataclastic regenerated roof load had a significant influence on the stability of the support.⑤The trinity coordinated support system was discussed which included the protection of coal wall,the control of roof and the stability of support.
作者
杨科
池小楼
刘钦节
刘文杰
刘帅
YANG Ke;CHI Xiaolou;LIU Qinjie;LIU Wenjie;LIU Shuai(State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan 232001,China;Key Laboratory of Mining Coal Safety and Efficiently Constructed by Anhui Province and Ministry of Education,Anhui University of Science and Technology,Huainan 232001,China;School of Resources and Civil Engineering,Northeastern University,Shenyang 110819,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2020年第9期3045-3053,共9页
Journal of China Coal Society
基金
国家自然科学基金重点资助项目(51634007)
安徽理工大学研究生创新基金资助项目(2019CX1003)
安徽省学术和技术带头人科研活动资助项目(2019D230)。
关键词
再生顶板
支架失稳
综采工作面
大倾角煤层
围岩破坏
cataclastic regenerated roof
support instability
fully mechanized mining face
steeply dipping seam
surrounding rock failure
