采空区遗留煤柱下开采动载矿压机理及防治技术研究

Research on dynamic load mine pressure mechanism and prevention technology of mining under leftover coal pillars of goaf

为分析上覆采空区遗留煤柱下工作面开采动载矿压显现机理,以榆家梁煤矿43303-2工作面在回采过程中顶板压架事故为研究对象,结合理论分析和现场勘测等手段,计算出4-2煤煤柱载荷、塑性破坏范围和底板扰动破坏带深度,建立上覆遗留煤柱失稳模型,确定工作面出煤柱开采强矿压灾害施载体、过渡体及承载体3个主控环节及其主要影响因素。研究表明:压架事故发生的4个主要原因为上覆煤柱应力集中,周期来压也是顶板垮落的原因之一,来压突然,推采速度过快。因此,提出地面深孔爆破,高压水预裂顶板治理措施,并在现场进行应用,最终使43303-2工作面周期来压步距减小,动载矿压显现程度降低,实现“顶板运动可控、顶板压力分次化解”的目的,避免了压架事故的发生。

In order to analyze the mechanism of the dynamic-loaded mine pressure manifestation of the mining face under the coal pillars leftover in the overlying goaf,the top plate support is crushed accident during the stoping process of the No.43303-2 working face of Yujialiang Coal Mine as the research object,combined with theoretical analysis and site investigation means,calculate 4-2 coal pillar load,plastic failure range and floor rock failure depth,establish the instability model of the overlying leftover coal pillars,determine the three main control links and main influence factors of the disasters of strong ore pressure disaster of coal pillar mining in working face as the carrier body,the transition body and the bearing body.Four main reasons for the stent is crushed accident are obtained:the stress concentration of the overlying coal pillar,the periodic pressure is also one of the reasons for the roof collapse,coming pressure suddenly,and the excessive speed.Therefore,Put forward ground deep-hole blasting and high-pressure water pre-splitting roof governance measures.and applied in the field,and finally reduce the periodic weighting length of No.43303-2 working face,and reduce the apparent degree of dynamic load mine pressure.,the purpose of"roof movement is controllable and the pressure of the roof is resolved in stages"is realized,avoided the occurrence of pressure rack accidents.