摘要
为了更加形象地研究顶煤冒放形态特征、宏观地把破碎的散体看作非理想状态下随机流动的松散介质.以某矿1302N大采高综放工作面为工程背景,利用离散元散体颗粒流软件PFC2D建立放顶煤二维横剖面模型,主要研究顶煤位移、煤矸动场变化、放出体衍化以及超前支承压力分布等现象.研究对比得出:顶煤流动规律方面,走向上放煤步距增大,顶煤的始动点边界线前移,顶煤运移范围增大;倾向上间隔放煤的煤损主要集中于同一轮放煤支架间的漏斗煤损.煤矸流场规律方面,采高增大煤矸分界线逐渐变陡;放煤步距增大,煤矸分界线始终保持双线形态前移.矿压显现规律方面,顶煤的硬度增大,顶煤分区中范围逐渐缩小,即超前支承压力峰值区向煤壁靠拢;采放比增大,超前支承压力峰值区远离煤壁,综放开采顶煤破碎后的流动特点和运移路径的数值模拟研究,有利于掌握散体顶煤的放出规律,据此对放煤工艺参数进行针对性的优化设计,对提高煤炭资源采出率具有重要意义.
In order to more vividly study the morphological characteristics of top coal caving,the broken loose body is regarded as a random flowing loose medium in a non ideal state.Taking the 1302N fully mechanized top coal caving working face of a mine as the engineering background,a two-dimensional cross-sectional model of top coal caving is established by using the discrete element loose particle flow software PFC2D.The displacement of top coal,the change of dynamic field of coal gangue the evolution of caving body and the distribution of advance support pressure are mainly studied.Through research and comparison,it is concluded that in terms of the flow law of top coal,the step distance of top coal caving increases in the strike,the boundary line of the starting point of top coal moves forward,and the movement range of top coal increases.The coal loss of interval coal drawing tends to be mainly concentrated in the funnel coal loss between the coal drawing supports of the same round.In terms of the flow field law of coal gangue,the coal gangue boundary becomes steeper with the increase of mining height.With the increase of the coal drawing step,the coal gangue boundary always keeps a double line shape and moves forward.In terms of the law of rock pressure manifestation,the hardness of the top coal increases,and the range in the top coal partition gradually decreases,that is,the peak area of the leading bearing pressure approaches the coal wall.With the increase of mining caving ratio,the peak area of leading bearing pressure is far away from the coal wall.The numerical simulation research on the flow characteristics and transportation path of the broken top coal in fully mechanized top coal caving is beneficial for grasping the release law of loose top coal,and based on this,targeted optimization design of coal drawing process parameters is of great significance for improving the coal resource recovery rate.
作者
徐壮飞
贾尚伟
王海洋
谢炎霖
XU Zhuangfei;JIA Shangwei;WANG Haiyang;XIE Yanlin(Shandong Gold Mining(Linglong)Co.Ltd.,Zhaoyuan 265400,China;Henan Province Rock and Mineral Testing Center,Zhengzhou 450012,China;Henan Institute of Geophysical and Space Information,Zhengzhou 450009,China)
出处
《河南科学》
2023年第8期1167-1175,共9页
Henan Science
基金
国家自然科学基金煤炭联合基金重点项目(U1361209)。
