摘要
为了分析浅埋薄基岩沿空掘巷围岩结构形成及失稳机理,根据浅埋薄基岩沿空掘巷覆岩破断特征,建立窄煤柱-实体煤-基本顶-覆岩共同作用的围岩结构受力模型,即"外伸梁"结构模型。通过对外伸梁结构的力学分析,揭示基本顶与窄煤柱对围岩稳定性的耦合作用机理,确定基本顶侧向极限悬跨度、窄煤柱压力及宽度等参数的计算公式。推导外伸梁结构系统平衡时需满足的解析条件以及稳定性判别条件,得到窄煤柱宽度与煤柱抗压强度成反比,且随基本顶抗剪强度增强而增大的强度关系。南梁煤矿30100工作面沿空掘巷窄煤柱宽度确定的实践表明,依据外伸梁结构模型确定的基本顶侧向极限悬跨度与其周期来压步距近似相等,窄煤柱宽度参数合理。
In order to analyze the formation and instability mechanism of surrounding rock structure of gob-side entry driving in shallow and thin bedrock,based on the fracture characteristics of overburden rock of shallow and thin bedrock gob-side entry driving,the stress model of surrounding rock structure of narrow pillar-solid coal-basic roof-overburden rock,i.e.,the structure model of"overhanging beam"has been established.Through the mechanical analysis of the overhanging beam structure,the coupling mechanism between the basic roof and the narrow coal pillar on the stability of surrounding rock has been revealed,and the calculation formula of the lateral limit suspension span of the basic roof,the pressure and width of the narrow coal pillar and other parameters have been determined.The analytical conditions and stability judgement conditions for the equilibrium of the overhanging beam structural system have been derived.And it has been found that the strength relationship between the width of narrow coal pillar and the compressive strength of coal pillar is inversely proportional,and it increases with the increase of the shear strength of the basic roof.The practice of determining the width of narrow coal pillar in working face 30100 of Nanliang coal mine has shown that the lateral limit suspension span of the basic roof determined based on the overhanging beam structure model is approximately equal to its periodic step,and the width of the narrow coal pillar is reasonable.
作者
张杰
刘清洲
孙遥
蔡维山
张建辰
陈诚
ZHANG Jie;LIU Qingzhou;SUN Yao;CAI Weishan;ZHANG Jianchen;CHEN Cheng(School of Energy Engineering,Xi’an University of Science and Technology,Xi’an,Shaanxi 710054,China;Shaanxi Guojiahe Coal Industry Co Ltd,Baoji,Shaanxi 721500,China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2020年第4期647-654,共8页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51774229,51474173)
陕西省创新能力支撑计划-科技创新团队项目(2018TD-038)
煤炭开采水资源保护与利用国家重点实验室开放基金项目(SHJT-17-42.3)
关键词
浅埋煤层
薄基岩
沿空掘巷
围岩结构
稳定性
shallow buried coal seam
thin bedrock
gob-side entry driving
surrounding rock structure
stability
