摘要
针对特厚煤层下分层工作面末采期间回撤通道围岩控制难题,以大柳塔煤矿活鸡兔井1-2特厚煤层为研究背景,通过数值模拟及现场实测的方法,对末采期间回撤通道围岩应力及塑性区演化分布展开研究,提出围岩控制方案并成功应用。结果表明,特厚煤层下分层工作面过上分层采空区末采贯通前,下分层回撤通道围岩垂直应力场略微增大,工作面前方剩余煤柱塑性屈服,回撤通道围岩塑性区基本不发生再扩展;至末采贯通时,回撤通道区段煤柱帮围岩垂直应力集中程度显著增大,工作面及回撤通道围岩塑性区扩展剧烈,围岩变形破坏较为严重,易导致矿井动力灾害发生。根据末采期间工作面及回撤通道围岩塑性区分布,确定回撤通道采用支护(锚杆索+网+钢带)-改性(注浆)的协同控制方案,现场应用取得良好效果。
In view of the problem of surrounding rock control of the retreat channel during the final mining period of the working face in the lower slice of the extra-thick coal seam, taking the 1-2extra-thick coal seam in Huojitu well of Daliuta Coal Mine as the research background, through the methods of numerical simulation and field measurement, the stress and plastic zone evolution distribution of the surrounding rock of the retreat channel during the final mining period are studied, and the surrounding rock control scheme is proposed and successfully applied.The results show that the vertical stress field of the surrounding rock of the lower layer retreat channel slightly increases before the lower layer working face of the extra thick coal seam passes through the final mining of the upper layer goaf, the remaining coal pillar in front of the working face plastic yield, and the plastic zone of surrounding rock in the retreat channel basically does not expand.When the final mining is completed, the vertical stress concentration of the surrounding rock of the coal pillar wall in the retreat channel section increases significantly, the plastic zone of the surrounding rock of the working face and the retreat channel expands violently, and the surrounding rock deformation and damage are relatively serious, which is easy to lead to the occurrence of mine dynamic disasters.According to the plastic zone distribution of the surrounding rock of the working face and the retreat channel during the final mining period, the collaborative control scheme of supporting(anchor cable+net+steel belt)and modifying(grouting)was determined for the retreat channel, and good effect was achieved in the field application.
作者
贾振斌
陈世江
田银素
JIA Zhenbin;CHEN Shijiang;TIAN Yinsu(College of Mining and Coal,Inner Mongolia University of Science and Technology,Baotou 014010,China;Daliuta Coal Mine,CHN Energy Shendong Coal Group Co.,Ltd.,Yulin 719315,China;Technology Research Institute,CHN Energy Shendong Coal Group Co.,Ltd.,Yulin 719315,China)
出处
《陕西煤炭》
2023年第2期20-25,共6页
Shaanxi Coal
基金
内蒙古自治区高等学校科学研究项目(NJYT-20-A21)。
关键词
特厚煤层
围岩控制
回撤通道
塑性区
分层开采
extra-thick coal seam
surrounding rock control
retreat channel
the plastic zone
slicing mining
