摘要
针对忻州窑煤矿11#煤层回采时临空煤柱侧巷道多发冲击地压的现状,在煤岩物理力学性质测试和冲击地压发生规律分析的基础上,通过计算坚硬悬顶下煤柱的受力状态,分析了临空煤柱巷道侧冲击地压的成因和受夹持煤体的冲击失稳过程,根据11#煤层及顶底板条件,制定了利用瓦斯巷开展断顶卸压爆破的解危方案。研究发现,临空侧煤柱的冲击失稳与工作面周期来压具有相关性,强制放顶不到位造成煤柱两侧形成坚硬长悬板,是诱发煤柱冲击失稳的能量来源;断顶卸压爆破可以有效切断坚硬悬板对煤柱的应力传递,电磁辐射、矿压和微震等监测数据显示,断顶爆破后煤帮电磁辐射强度降低约68%,单体液压支柱应力降低约20%,钻孔应力降低约80%,有效降低了煤柱的冲击危险性。
Facing frequent coal bumps in the side of invading coal pillar during the stoping of coal seam 11 of Xinzhouyao coal mine, based on tests of physical and mechanical properties of coal and the analysis of occurrence regularity of coal bumps, the genesis of the coal bumps in the side of invading coal pillar and the process of impactive instability of the clamping coal were analyzed through the cal- culation of stress state of coal pillar, and the danger-relief scheme of blasting method of roof breaking and pressure relief through gas tunnel was made using according to the conditions of coal seam 11 and its roof and floor. The results have shown that the impactive instability of invading coal pillar is relative to the periodic pressure of the working face： the forced caving out of place causes a hard long hanging plate in both sides of the coal pillar, which is the energy source of the impactive instability of coal pillar; the blasting method of roof breaking and pressure relief can efficiently cut the stress transfer of hard long hanging plate to coal pillar： as the monitoring data of the electromagnetic radiation, mine pressure and slight shock have shown, after blasting, the electromagnetic radiation intensity beside the coal pillar reduced by 68%, the stresses of single hydraulic prop reduced by 20%, and the drilling stress reduced by 80%, which effectively lowered the coal bump hazard of the coal pillar.
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2017年第1期54-59,66,共7页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(51504015)
中国矿业大学煤炭资源与安全开采国家重点实验室开放基金项目(SKLCRSM15KFB02)
中央高校基本科研业务费项目(FRF-TP-15-054A1)
关键词
冲击地压
坚硬顶板
断顶爆破
电磁辐射
coal bumps
hard roof
blasting method with roof-broken
electromagnetic radiation
