沙曲一号煤矿坚硬顶板悬顶液态二氧化碳相变致裂研究  

Research on fracturing of hard roof in Shaqu No.1 Coal Mine induced by liquid carbon dioxide phase transition

作　　者：郭宇 GUO Yu(Shaqu No.1 Coal Mine,Huajin Coking Coal Com pany Limited,Lyuliang 033300,China)

机构地区：[1]华晋焦煤有限责任公司沙曲一号煤矿,山西吕梁033300

出　　处：《建井技术》2025年第2期13-19,共7页Mine Construction Technology

基　　金：国家自然科学基金面上项目(51874014)。

摘　　要：煤矿坚硬顶板工作面开采易产生巷道端头悬顶过大等问题,进而导致瓦斯积聚、顶板大面积垮塌等安全隐患。针对沙曲一号煤矿4501工作面坚硬顶板,运用液态二氧化碳相变致裂技术对悬顶进行致裂切顶,并通过窥视仪观测钻孔裂纹扩展发育情况,评估致裂效果。现场实践表明,钻孔内观测到多条裂纹扩展、贯通与延伸,设计的3次循环起爆方案有效破碎顶板岩石,完成切顶目标。进一步研究发现:三角形布孔方案比矩形布孔方案致裂效果更好。爆破后孔口位置出现环形破碎区,微裂纹沿着主裂隙方向扩展。钻孔的裂缝形态及发育程度受到孔壁岩性、起爆方式等因素影响。通过调控起爆顺序可优化裂纹连通性,双孔联合起爆破岩效果更好。In coal mining,hard roof conditions often lead to challenges such as excessive suspended roof at roadway ends,posing safety risks like gas accumulation and large-scale roof falls.Focusing on the 4501 working face hard roof of the Shaqu No.1 Coal Mine,this study applied liquid carbon dioxide phase-transition fracturing technology to fracture and control suspended roofs.The development of crack expansion in the borehole was also observed by a speculum to evaluate the fracturing effect.Field practice has shown that multiple cracks were observed in the drill holes to expand,penetrate and extend,and the three-cycle detonation program designed in this paper effectively broke up the roof rock and accomplished the goal of cutting the roof.Further studies revealed that the triangular hole placement scheme was more effective than the rectangular hole placement scheme in terms of fracturing.Ring-shaped crushing zone at the location of the hole after blasting,with microcracks expanding in the direction of the main fissure.The fracture pattern and the degree of development of the drill hole is affected by the wall lithology,detonation method and other factors.Optimize fracture connectivity by controlling the detonation sequence,with better results for double-hole joint rock blasting.

关 键 词：煤矿悬顶 CO_(2)相变致裂 裂纹扩展 循环爆破 破岩技术 

分 类 号：TD235.4[矿业工程—矿井建设] TD712.6