急倾斜煤层残留煤柱下综放工作面动力灾害防治研究

发布时间：2018-05-31 15:47

本文选题：急倾斜特厚煤层 + 残留煤柱　；参考：《西安科技大学》2017年硕士论文

【摘要】：新疆是国家规划建设的第十四个高起点、高标准、高效益的亿吨级大型煤炭基地,也是“一带一路”经济带规划建设的主体能源基地。由神华新疆能源有限责任公司主采的乌鲁木齐矿区急倾斜复杂难采特厚煤层占世界急倾斜煤层储量的30%。煤炭资源赋存环境复杂(45°~87°),安全开采难度极大,动力灾害频发。碱沟煤矿B3-6煤层属急倾斜特厚煤层(87°),采用水平分段综采放顶煤回采方法回收顶煤,段高24m。+495水平B3-6回采工作面通过上覆结构尺寸为长·宽·高(120m·50m·108m)的残留煤柱。工作面经过煤柱时在开采扰动作用下形成复杂的空间结构——工作面夹持于顶、岩柱及残留煤柱之间,围岩在静-动载荷作用下极易诱发动力灾害。通过理论分析认为残留煤柱诱发动力灾害主要有以下三点:a.煤柱夹持于顶底板之间造成水平应力集中从而引起剪应力大大增加,使煤柱易发生剪切破坏;b.煤柱的存在使得B3-6煤层与B1-2煤层中间岩柱内部应力增大,煤柱内部应力与岩柱自重G、水平应力q0及煤柱段高h0呈正相关;c.在走向方向煤柱受工作面采动影响,煤柱内部集中应力与工作面超前支承应力互相叠加,使得在残留煤柱危险范围内,工作面前方应力大大增加。采用数值模拟分析煤柱未受采动和采动影响下煤柱内部应力变化情况,得出:在残留煤柱前方60~120m处、0~60m处,-60~0m处工作面支架顶部应力具有明显的分区特性,应力平稳区(60~120m处)、应力过渡区(0~60m处)、应力叠加区(-60~0m),在应力过渡区与应力叠加区应力集中明显,受采动影响极易诱发动力灾害。通过在石门内布置扇形注水、爆破孔;+495B3巷布置高阶段超前爆破孔;正常的超前预裂注水、爆破孔;岩柱预裂注水、爆破孔及顶板深孔预裂爆破孔。对煤柱危险区域充分卸压,实现工作面安全、高效通过残留煤柱危险区域。本研究对于实现急倾斜特厚煤层工作面过残留煤柱安全高效开采及岩柱稳定性控制具有指导意义。
[Abstract]:Xinjiang is the 14th high starting point, high standard and high benefit large coal base of national planning and construction. It is also the main energy base of "Belt and Road" economic belt planning and construction. Urumqi mining area, mainly produced by Shenhua Xinjiang Energy Co., Ltd, accounts for 30% of the world's steep seam reserves. The complex environment of coal resources is 45 掳/ 87 掳/ m, the difficulty of safe mining is great, and the dynamic disasters occur frequently. The coal bed B3-6 of Jiegou coal mine belongs to the steep inclined and super thick coal seam (87 掳). The top coal is recovered by using the method of level sublevel fully mechanized caving, the height of the section is 24m. 495 horizontal B3-6 mining face passes through the residual coal pillar with overburden structure size of 120m 50m 108m. When the coal face passes through the coal pillar, the complex spatial structure is formed under the action of mining disturbance-the face is clamped in the roof, the rock pillar and the residual coal pillar, the surrounding rock is easy to induce the dynamic disaster under the action of static and dynamic load. Through theoretical analysis, it is concluded that the dynamic disasters induced by residual coal pillars are mainly as follows: a. The horizontal stress concentration caused by the coal pillar clamping between the top and the floor leads to the increase of the shear stress, which makes the coal pillar prone to shear failure. The existence of coal pillar increases the internal stress of intermediate rock pillar in coal bed B3-6 and coal bed B1-2, and there is a positive correlation between the internal stress of coal pillar and the weight of rock pillar, the horizontal stress Q _ 0 and the height of coal pillar section h _ 0. In the direction of strike, the coal pillar is affected by the mining movement of the working face, and the internal concentrated stress of the pillar and the leading supporting stress of the working face are superimposed on each other, which makes the stress in the front of the working face increase greatly in the dangerous range of the residual pillar. By using numerical simulation to analyze the change of internal stress of coal pillar without the influence of mining movement and mining movement, it is concluded that the stress at the top of the support in front of the residual coal pillar at 60 ~ 120 m and 0 ~ 60 ~ 60 m in front of the residual coal pillar has obvious zonation characteristics. The stress is stable at 60m, stress transition is 60m, and stress superposition is 60m. The stress concentration is obvious in the stress transition area and the stress superposition area, and the dynamic disaster is easily induced by the influence of mining. By arranging fan water injection, blasting hole in Shimen, advanced blasting hole in high stage in 495B3 lane, normal pre splitting water injection, blasting hole, pre splitting water injection in rock column, blasting hole and deep roof hole in pre splitting blasting hole. Fully release the pressure to the dangerous area of coal pillar, realize the safety of working face and pass through the dangerous area of residual coal pillar efficiently. This study is of guiding significance for the safety and high efficiency mining and the control of rock pillar stability in the face of steep and thick coal seam.
【学位授予单位】：西安科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD355

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