摘要
基于倾斜中厚煤层沿空掘巷与支护技术展开研究。首先通过构建力学模型,依据基本顶最大弯矩确定基本顶的断裂位置及断裂形式,计算得在距离煤柱帮17.57 m处基本顶达到弯矩最大值23.02 MN·m,并进一步确定断裂线位于实体煤上方;结合"内外应力场"理论,确定在当前覆岩力学环境下"内应力场"范围为15.89 m;综合考虑煤柱的空间关系,分析巷道围岩煤柱尺寸,确定窄煤柱水平错距为7.37 m,竖直错距为2.40 m;综合以上分析确定区段煤柱留设尺寸范围为7~12 m,通过FLAC3D数值模拟软件对不同煤柱尺寸的应力场、塑性区分布进行计算分析,对掘进和回采两个阶段下不同煤柱尺寸条件下稳定性进行研究和验证,最终确定窄煤柱的合理宽度为8 m。然后根据倾斜中厚煤层错层位外错式巷道布置形式所具有的立体化空间形式,提出错层位外错式区段间相邻巷道联合支护技术并对其技术特点进行理论分析;基于围岩松动圈支护理论,通过计算确定区段间相邻巷道联合支护参数并利用FLAC3D数值模拟软件对区段间相邻巷道联合支护方案和矿方原支护方案进行模拟,分别从支护应力场、塑性区分布和围岩相对变形率3方面对掘巷和回采阶段下两支护方案的效果进行验证,最终结果表明区段间相邻巷道联合支护方案相对于矿方原始支护方案,更有利于巷道围岩的变形控制。
Research is conducted on the gob-side gateroad driving and support technology in an inclined and medium-thick coal seam.By constructing a mechanical model,the fracture position and fracture form of the main roof are determined according to the maximum bending moment of the main roof.It is calculated that the main top reaches the maximum bending moment at a distance of 17.57 m from the coal pillar and the maximum bending moment is 23.02 MN·m,which further determines that the fracture position is located on the side of the solid coal.Combined with the "inside and outside stress field" theory,the calculated "internal stress field" range is 15.89 m.Considering the space relationship of the roadway,the horizontal offset of the narrow coal pillar is determined to be 7.37 m and the vertical offset is 2.40 m.The above experimental analysis determines that the experimental range of the section coal pillars is 7-12 m.The stress field and plastic zone distribution of different coal pillar sizes are calculated and analyzed by the FLAC3 D numerical simulation software and the dimensional stability of different coal pillars is studied and verified under the two stages of excavation and mining.The reasonable width of the narrow coal pillar is finally determined to be 8 m.Based on the spatial structure characteristics of adjacent roadways in split-level roadway arrangement,the combined support technology is proposed and its technical characteristics are analyzed theoretically.The broken zone theory is used to determine the joint support parameters of the adjacent roadway and the FLAC3 D numerical simulation software is used to simulate the combined support scheme and the original support plan.The effects of the two support schemes under different stages are verified from the aspects of support stress field,plastic zone distribution and relative deformation rate of surrounding rock.The final result shows that the combined support scheme is more conducive to the deformation control of the surrounding rock of the roadway.
作者
王志强
郭磊
苏泽华
王树帅
沈聪
WANG Zhiqiang;GUO Lei;SU Zehua;WANG Shushuai;SHEN Cong(School of Energy and Mining Engineering,China University of Mining&Technology(Beijing),Beijing 100083,China;Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources,China University of Mining and Technology(Beijing),Beijing 100083,China;National Demonstration Center for Experimental Safe Coal Mining and Geological Guarantee Education,China University of Mining and Technology(Beijing),Beijing 100083,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2020年第2期542-555,共14页
Journal of China Coal Society
基金
国家自然科学基金青年基金资助项目(51404270)
国家自然科学基金面上资助项目(51774289)
中央高校基本科研业务费专项资金资助项目(2011QZ06)
关键词
沿空掘巷
窄煤柱
错层位
外错式
相邻区段巷道
联合支护
gob-side gateroad driving
narrow pillar
stagger arrangement
external-misaligned
adjacent roadways
combined support
