特厚坚硬顶板控制机理和弱化技术研究

Research on Control Mechanism and Weakening Technology of Thick and Hard Roof

为了探讨特厚坚硬顶板合理的弱化方法,以山西晋城某矿15号煤层特厚坚硬顶板为研究对象,建立了顶板初次断裂前的固支岩梁力学模型及两种爆破方式的顶板力学模型,采用现场调查、实验室实验和理论分析相结合的研究方法,系统研究了工作面坚硬顶板超前弱化的技术手段、布置方案和预裂爆破装药量,确定了坚硬顶板弱化的超前深孔预裂爆破技术方案,和8.63kg/孔的所需装药量。工业试验结果表明,该弱化方案能缓和顶板矿压显现,对于坚硬顶板弱化效果明显,有效地解决了特厚坚硬顶板的弱化问题。

In order to investigate a reasonable weakening approach for thick and hard roof,the 15 th coal seam with special thick and hard roof in Jincheng of Shanxi province was taken as the research object.A mechanical model of rock embedded beam before the initial fracture and another roof mechanical model based on two kinds of blasting were established.The hard roof weakening technology ahead of working face,layout schemes,and explosive load of pre-splitting blasting were studied with a combined method of field surveys,laboratory experiments and theoretical analysis.Then the pre-splitting blasting was determined as the weakening solution for thick and hard roof,and the required explosive load was 8.63 kg per hole.Field industrial tests results showed that the scheme can mitigate roof strata behavior and have obvious weakening effect for hard roof,which effectively solved the weakening problems of thick and hard roof.