近直立特厚煤层上覆煤柱下巷道掘进冲击地压防治实践研究

Research on prevention and control of rock burst during excavation of roadway under overlying coal pillars in near vertical thick coal seams

以近直立特厚煤层终采线煤柱下掘进过程中遇到冲击地压问题为工程背景,通过数值模拟、理论分析和现场实践的方法,研究了保护煤柱下方掘进面开采过程中冲击危险程度的变化,提出了相应的防治手段和检验措施。研究发现,巷道掘进影响了终采线煤柱区域应力分布状态,增加了终采线煤柱区域应力集中范围及冲击危险性;掘进工作面经过煤柱边缘应力集中区时,前方应力峰值较大,围岩冲击危险性较高。根据PDCA管理模式提出了理论分析→实施解危→效果验证→掘进实践→优化调整→效果验证的双循模式管控,通过实施迎头密集大孔径卸压孔和全方位高压注水软化等系统性防治工程,并采用微震、地音、电磁辐射等技术进行效果验证,实现了掘进工作面安全通过煤柱影响区域,为矿井冲击地压防治提供了参考和借鉴。

Based on engineering background of encountering problem of rock burst during excavation under coal pillar of near vertical thick coal seam stop mining line,this paper studies changes in the degree of rock burst risk during mining process of protecting excavation face under coal pillar through numerical simulation,theoretical analysis,and on-site practice,and proposes corresponding prevention and control measures and inspection measures.Research has found that roadway excavation affects the stress distribution status in the coal pillar area of the stop mining line,increasing the stress concentration range and impact risk in the coal pillar area of the stop mining line.When the excavation face passes through the stress concentration area at the edge of the coal pillar,the peak stress in front is relatively high,and the risk of surrounding rock impact is high.According to the PDCA management model,a dual cycle control model was proposed,which includes theoretical analysis,implementation of risk relief,effectiveness verification,excavation practice,optimization and adjustment,and effectiveness verification.Through the implementation of systematic prevention and control projects such as dense large aperture relief holes and all-round high-pressure water injection softening,and the use of microseismic,acoustic,electromagnetic radiation,and other technologies for effectiveness verification,the safe passage of the excavation face through the coal pillar affected area was achieved.This provides reference and reference for the prevention and control of mine rock burst.