工作面末采段深孔预裂切顶护巷技术研究  

Deep hole pre-split roof cutting and roadway protection in end mining of working face

作　　者：朱文庆 郝兵元[1] 刘世涛 任兴云 杨冉 ZHU Wen-qing;HAO Bing-yuan;LIU Shi-tao;REN Xing-yun;YANG Ran(College of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China;College of Safety and Emergency Management Engineering,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学矿业工程学院,山西太原030024 [2]太原理工大学安全与应急管理工程学院,山西太原030024

出　　处：《煤炭工程》2022年第5期97-103,共7页Coal Engineering

基　　金：国家自然科学基金(U1810104)。

摘　　要：针对工作面进入末采阶段后,由回采作业引起的采区大巷围岩变形失稳现象,基于超前支承压力分布力学模型,运用极限平衡理论及半平面解法,理论计算得出超前支承压力峰值位置、影响范围及采区大巷处应力大小,分析大巷处应力增高主要是由于工作面上覆岩层较为完整,加剧了超前支承压力的向前传递而引起的。因此,提出采用深孔预裂爆破技术,利用爆生裂隙的贯通形成结构弱面,从而破坏超前支承压力的传递路径,达到减小工作面采动影响范围及提高大巷围岩稳定性的目的;根据工程地质条件,定量分析选取爆破切顶关键参数,并运用数值模拟验证了方案合理性;通过现场工业性试验及矿压监测数据分析表明:在爆破切顶条件下,5^(#)、8^(#)测点顶底板移近量分别减少41%和55.5%,两帮移近量分别减少68.1%和74.8%,说明该方案可改善采区大巷应力环境,缩小超前支承压力的影响范围。In view of the surrounding rock deformation and instability of the mining district main roadway caused by the mining influence during working face enters end mining,based on the mechanical model of the distribution of the advance abutment pressure,the limit equilibrium theory and the half-plane solution method are used to theoretically calculate the peak value of the advance abutment pressure.The location,influence range and the stress at the main roadway are analyzed.The main reason for the stress increase in the main roadway is that the overlying stratum on the working face is relatively integrate,which intensifies the forward transmission of the advance abutment pressure.Therefore,it is proposed to use deep hole pre-split blasting technology,and the penetration of blasting cracks to form structural weak planes,thereby destroying the transmission path of the advance abutment pressure,so as to reduce the impact range of working face mining and improve the stability of the surrounding rock.According to the engineering geological conditions,quantitative analysis is applied to select the key parameters of blasting roof cutting,and numerical simulation is used to verify the rationality of the plan;on-site industrial test and mine pressure monitoring data analysis shows that:under blasting roof cutting conditions,at 5^(#)and 8^(#) measuring point,the convergence of the roof and floor is reduced by 41%and 55.5%,respectively,and the side wall convergence is reduced by 68.1%and 74.8%,respectively,indicating that this scheme can improve the stress environment of the main roadway in the mining area and reduce the influence range of the advance abutment pressure.

关 键 词：切顶卸压 超前支承压力 深孔爆破 工作面末采 切顶关键参数 极限平衡理论 

分 类 号：TD322[矿业工程—矿井建设]