告成矿25091下副巷（北段）深孔预裂爆破强化增透抽采技术研究

发布时间：2018-04-08 09:05

本文选题：深孔预裂爆破　切入点：瓦斯抽采　出处：《安徽理工大学》2017年硕士论文

【摘要】：郑州煤电集团告成煤矿25091下副巷(北段)揭煤区域主采二1煤,该区域煤层整体呈单斜构造,煤层厚度2.5～4.5m,平均3.5m,煤层倾角11～17°,平均14°,煤层透气性系数较差为0.0053m2/(MPa2·d),瓦斯含量17.25m3/t且原始瓦斯压力最大10.34MPa,给瓦斯治理工作带来极大的困难。因此,针对该煤层透气性差、瓦斯含量高、瓦斯压力超过防突规定、抽采困难容易诱发瓦斯灾害事故的特点,本文以25091下副巷(北段)揭煤区域为试验区,采用深孔预裂爆破强化增透抽采技术进行瓦斯治理。通过对国内外爆破致裂强化增透技术和机理进行总结,以理论研究为基础,利用数值模拟与相似模拟相结合对试验方案进行考察,并将优化后的方案实践于告成矿25091下副巷(北段)。通过将25091下副巷(北段)的可用爆破参数带入进行理论计算得到不耦合系数Kd=1.2533,径向不耦合爆破的单孔爆破裂隙影响半径是4.6m。同时利用建立Ls-Dyna数值模拟对比爆破孔中不同药柱位置对于爆破漏斗的形成的影响,并考察过煤岩交界面装药进行深孔预裂爆破情况下裂隙半径范围。说明过煤岩交界面装药爆破相对于煤层中爆破不仅可以对煤体本身带来拉伸损伤形成较为清晰的裂纹,而且通过对比两组试验模型X-Z和X-Y切面剖面图能够看出前者爆破孔向控制孔贯通的裂隙较好,说明进入煤层底板深孔预裂爆破能够保证裂隙范围至少达到4m。相似模拟过程中,通过观察两组模型的表面发现爆破后爆破孔会因为抛掷作用形成向四周扩散的漏斗状孔洞。这种现象在过"底板"爆破的一组尤为明显,爆破后会产生密度集中的裂纹,同时爆破孔径也会由圆心向控制孔扩展使得爆破孔的孔洞得以变大,进而形成的爆破漏斗更为典型,其爆破漏斗的直径为41mm超过爆破孔直径Φ12mm的3倍。通过对比郑煤集团告成煤矿25091下底抽巷(北段)的试验区进行深孔预裂爆破瓦斯抽采前后的瓦斯抽采浓度和抽采纯流量能够看出:设计单孔爆破裂隙影响半径为4.5m在径向不耦合爆破后瓦斯抽采浓度和纯量的最大值提升为之前的10.23倍和6.92倍,说明该方案下爆破后瓦斯流量和瓦斯纯量都有大幅降低,改善了抽采效果,达到了预期效果。
[Abstract]:Zhengzhou Coal and Power Group Goucheng Coal Mine 25091 Lower side roadway (North Section) main coal mining area 2 1 coal seam in this area as a whole monocline structure,The thickness of coal seam is 2.5 ~ 4.5m, the average is 3.5m. the inclined angle of coal seam is 1117 掳, the average is 14 掳, the permeability coefficient of coal seam is 0.0053m2/(MPa2 DU, the gas content is 17.25m3/t and the maximum original gas pressure is 10.34MPa, which brings great difficulties to the gas control work.Deep hole pre-splitting blasting was used to strengthen anti-penetration and drainage technology for gas treatment.Through summing up the anti-reflection technology and mechanism of blasting induced cracking at home and abroad, based on the theoretical study, the experimental scheme was investigated by combining numerical simulation with similar simulation.The optimized scheme was put into practice in 25091 sub-roadways of Gaocheng Mine (North Section).By introducing the available blasting parameters of 25091 secondary roadways (northern section) into the theoretical calculation, the uncoupling coefficient KDX 1.2533 is obtained, and the influence radius of single hole blasting crack of radial uncoupled blasting is 4.6 m.At the same time, the Ls-Dyna numerical simulation was used to compare the influence of different positions of charge column in blasting hole on the formation of blasting funnel, and the radius of fracture was investigated under the condition of deep-hole pre-splitting blasting with coal and rock interfacial charge.The results show that the interfacial blasting of coal and rock can not only cause tensile damage to the coal body but also form a clear crack in comparison with the blasting in coal seam.By comparing the X-Z and X-Y sections of the two test models, it can be seen that the former has a better fracture through the controlled hole in the direction of the blasting hole, which indicates that the pre-splitting blasting into the deep hole of the coal seam floor can ensure the crack range to be at least 4 m.In the process of similar simulation, the surface of two groups of models is observed and it is found that the blasting hole will form a funnel hole diffusing in all directions because of the throwing action.This phenomenon is especially obvious in the group of blasting through the "bottom plate". After blasting, there will be cracks with concentrated density. At the same time, the diameter of the blasting will expand from the center of the blasting to the control hole, so that the hole in the blasting hole can be enlarged.The blasting funnel formed is more typical, and the diameter of the blasting funnel is more than 3 times that of the diameter of the blasting hole 桅 12mm.By comparing the concentration of gas extraction and the pure flow rate of gas extraction before and after deep hole pre-splitting blasting in the test area of 25091 bottom drainage roadway (northern section) of Goucheng Coal Mine of Zheng Coal Group, it can be seen that the influence radius of the design of single hole blasting crack is as follows: 1.The maximum value of gas extraction concentration and scalar quantity of 4.5m after radial decoupling blasting is 10.23 times and 6.92 times higher than that before.The results show that the gas discharge and the gas scalar quantity are greatly reduced after blasting, and the drainage effect is improved and the expected effect is achieved.
【学位授予单位】：安徽理工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TD712.6

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