采矿与安全工程学报 ›› 2016, Vol. 33 ›› Issue (4): 692-698.

• 论文 • 上一篇    下一篇

非充分稳定覆岩下综放沿空掘巷窄煤柱变形机理

  

  1. 1.中国矿业大学矿业工程学院,深部煤炭资源开采教育部重点实验室,江苏 徐州  2211162.兖州煤业股份有限公司鲍店煤矿,山东 邹城  273500
  • 收稿日期:2015-12-26 出版日期:2016-07-15 发布日期:2016-07-25
  • 作者简介:张洪伟(1990—),男,山东省邹城市人,博士研究生,从事矿山压力与岩层控制、高温岩石力学及地热开发等方面的研究。
  • 基金资助:

    国家自然科学基金项目(51504236);江苏高校优势学科建设平台项目

Deformation mechanism of narrow coal pillar in the fully-mechanized gob-side entry with incompletely stable overlying strata

  • Received:2015-12-26 Online:2016-07-15 Published:2016-07-25

摘要: 为了掌握非充分稳定覆岩下综放沿空掘巷窄煤柱变形机理,采用矿用钻孔窥视仪对非充分稳定覆岩下综放沿空掘巷窄煤柱进行了钻孔摄像观测,提出了“基本测量尺度-破碎等级逐级评判”钻孔裂隙统计方法,研究分析了裂隙分布规律。研究表明:1) 非充分稳定覆岩条件下综放沿空掘巷窄煤柱裂隙多以径向裂隙及离层形式存在,异常破碎带主要出现在煤柱两端,煤柱中部多存在间隔分布的径向裂隙,微小裂隙几乎全部存在于煤柱中部。2) 按照破碎程度的不同,窄煤柱可分为3个区域,即近巷破碎区A、中部稳定区B和沿空破碎区CB区更靠近C区,整体区域分布表现出几何上的不对称性。3) 控制该类煤柱变形的基本思路是控制基本顶断裂后关键块的回转和滑移,提出了“控回转、重锚固、强限制”内外联合控制方法。

关键词: 沿空掘巷, 窄煤柱, 非充分稳定覆岩, 变形特征, 钻孔观测

Abstract: In order to understand the deformation mechanism of the narrow coal pillar in gob-side entry employing TCC under unstable overlying strata, borehole inspection camera has been utilized to observe the boreholes in the narrow coal pillar. Evaluation method of broken level based on the basic measuring scale has been proposed to undertake the statistical analysis of borehole fracture and the characteristic of fracture distribution has also been investigated. The results have shown that: 1) Transverse fractures and beddings are the two main fracture forms of the pillar; abnormal fracture zone is mainly located at both sides of the pillar; besides, there exist many transverse fractures with certain space intervals and small fractures in the middle of the coal pillar. 2) According to different broken levels, the pillar can be divided into three zones, viz., fracture zone A, stable zone B and fracture zone C; fracture zone A is near the roadway while fracture zone C is near the gob. Because of the asymmetry of the geometric distribution of these three zones, the stable zone is closer to the fracture zone C. 3) The key to control the deformation of the coal pillar is to control the rotating and slippage of the key block, and its coupling support control method has been proposed.

Key words: gob-side entry, narrow coal pillar, unstable overlying strata, deformation characteristic, borehole monitoring