摘要
在断层和采动影响下,下盘工作面断层侧煤柱宽度制约着工作面的安全生产。以黄陵煤矿二盘区203下盘工作面为工程背景,采用理论分析、数值模拟和相似模拟相结合的方法,研究上盘工作面采空后,下盘工作面断层侧煤柱上方载荷与煤柱尺寸之间的关系,揭示煤柱宽度为30,26,22,20,13和6m时的位移、应力演化及塑性区分布特征,分析煤柱宽度为30m时的覆岩结构特征,并通过综合分析,优化了工作面合理煤柱宽度。研究表明:上盘工作面采空时,在断层和采动的影响下,随着煤柱宽度的减小,下盘工作面断层侧煤柱上方的载荷分为载荷降低区、载荷过渡区和载荷稳定区;当煤柱宽度为30m时,下盘工作面断层侧高位岩层出现离层,煤柱上方应力集中程度大于另一侧,承载能力强,稳定性高;当煤柱宽度减小至22m时,靠近断层侧的顶板最大下沉量和应力集中程度显著增大,煤柱开始发生塑性破坏,承载能力逐渐减弱;当煤柱宽度减小到13m时,断层侧塑性区向工作面两端及上方发展至贯通煤柱,煤柱稳定性较差;当煤柱宽度减小至6m时,靠近断层侧顶板最大下沉量和应力集中程度继续增大,塑性区继续发育。通过相似模拟试验研究发现,当煤柱宽度为30m时,顶板垮落并充填采空区,下盘工作面断层侧煤柱上方无明显变化。经综合分析,确定下盘工作面断层侧煤柱的合理宽度为18~22m,可提高工作面回采率,同时可保证工作面安全生产。
Under the influence of faults and mining,the coal pillars width on the fault side of the foot wall working face restricts the safe and stable production of the working face.Based on the engineering background of the 203 foot wall working face in the second panel of Huangling Coal Mine,a combination of theoretical analysis,numerical simulation,and similarity simulation was used to study the relationship between the load above the fault side coal pillar and the size of the coal pillar after the upper working face was mined out.The displacement,stress evolution,and plastic zone distribution characteristics under the coal pillar widths of 30,26,22,20,13,and 6 meters were revealed,and the overburden structure characteristics with coal pillar width of 30 meters were analyzed.Through comprehensive analysis,the reasonable coal pillars width in the working face was optimized.The results show that when the upper working face is mined out,under the influence of fault and mining,with the decrease of coal pillar width,the load above the coal pillar on the fault side of the foot wall working face is divided into load reduction zone,load transition zone and load stability zone.When the coal pillar width is 30 m,the high rock layer on the fault side of the foot wall working face separates,and the stress concentration degree above the coal pillar is greater than that on the other side,with strong bearing capacity and high stability.When the coal pillar width is reduced to 22 m,the maximum subsidence and stress concentration of the roof near the fault side increase significantly,and the plastic failure of the coal pillar begins to occur,and the bearing capacity gradually weakens.When the the coal pillar width is reduced to 13 m,the plastic zone on the fault side develops towards both ends and above the working face to connect the coal pillar,resulting in poor stability of the coal pillar.When the coal pillar width is reduced to 6 m,the maximum subsidence and stress concentration of the roof on the fault side continue to increase,a
作者
伍永平
曹建利
孙明明
张浩
皇甫靖宇
杜玉乾
胡涛
WU Yongping;CAO Jianli;SUN Mingming;ZHANG Hao;HUANGFU Jingyu;DU Yuqian;HU Tao(Key Laboratory of Western Mine Exploitation and Hazard Prevention Ministry of Education,Xi'an University of Science and Technology,Xi'an,Shaanxi 710054,China;College of Energy Science and Engineering,Xi'an University of Science and Technology,Xi'an,Shaanxi 710054,China;China Coal Energy Research Institute Co.,Ltd.,Xi'an,Shaanxi 710054,China)
出处
《矿业研究与开发》
CAS
北大核心
2024年第4期46-54,共9页
Mining Research and Development
基金
国家自然科学基金项目(51974230,52204151,52104147).
关键词
上盘采空
下盘开采
断层侧煤柱
煤柱宽度
Mined out of upper wall
Mining of foot wall
Coal pillar on the fault side
Coal pillar width
