深部综采工作面厚顶板爆破控灾技术及应用

1.中天合创能源有限责任公司 葫芦素矿井,内蒙古 鄂尔多斯 017000; 2.天地科技股份有限公司 开采设计事业部,北京 100013; 3.西安科技大学 能源学院,陕西 西安 710054

深部开采; 厚顶板; 深孔爆破; 裂纹扩展; 动力灾害

Technology and application of blasting crack aiming at thick roof of deep fully mechanized mining face
MA Yan-xiong1,LIANG Zhi-jun1,WU Zhao-hua2,WU Fan3

(1.Hulusu Coal Mine,Zhongtian Hechuang Energy Co.,Ltd.,Ordos 017000,China; 2.Coal Mining and Designing Department,Tiandi Science and Technology Co.,Ltd.,Beijing 100013,China; 3.College of Energy Science and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China)

deep mining; thick roof; deep holes blasting; crack propagation; dynamic hazards

DOI: 10.13800/j.cnki.xakjdxxb.2017.0511

备注

深部综采工作面厚顶板失稳极易诱发煤岩动力灾害。针对深部综采工作面爆破处理厚顶板问题,在考虑煤岩本构关系基础上,建立爆破弱化顶板力学分析模型,并采用LS-DYNA有限元程序、ALE(流固耦合)算法及3DEC离散单元法,计算深部岩体爆破裂纹扩展影响半径,确定顶板爆破位置和断顶卸压高度,为爆破减灾方案提供依据。研究结果表明:爆破卸压作用力学行为表现为消除应力集中区和支座B力矩MB; 覆岩爆破主裂纹扩展最大影响半径2.60 m,有效应力波最大影响半径5.65 m,确定双炮孔距10 m,主裂纹扩展主方向为沿径向扩展,次裂纹扩展方向具有随机性; 通过实施21102工作面顶板深孔爆破方案后,统计分析支架工作阻力并验证了爆破诱导顶板断裂效果显著。

Dynamic hazards are easily induced by thick roof instability in deep fully mechanized mining face.This paper focus on the controlling problem of thick roof of deep fully mechanized mining face.The mechanical analysis model of roof blasting has been built on the basis of considering coal-rock constitutive relations.Meanwhile,crack propagation radius,blasting positions and height of deep rock mass are calculated using finite element program(LS-DYNA),fluid-solid coupling algorithm(Arbitrary Lagrange-Euler,ALE)and discrete element method(3DEC).These results could provide significant guidance for hazards prevention by blasting.Results show that stress concentration areas and moment of B support point(MB)could be removed in reacting on mechanical behavior of blasting.Also,the maximum radius of crack propagation of deep rock mass is 2.60 m and the maximum radius of effective stress wave is 5.65 m.Therefore,the distance between blasting holes are designed as 10 m.Main crack propagation extends along the radial direction,and secondary crack propagation direction shows randomness.Finally,analysis on effective working resistance of hydraulic support proves that blasting has an obvious effect on the roof fracture.