缓斜极厚矿体开采安全切顶厚度研究  

Safety roof cutting thickness in mining gently inclined and extremely thick ore body

作　　者：谢承煜[1] 罗周全[1] 贾楠[1] 杨彪[1] 程贵海[2] 

机构地区：[1]中南大学资源与安全工程学院,湖南长沙410083 [2]广西大学资源与冶金学院,广西南宁530004

出　　处：《采矿与安全工程学报》2013年第2期278-284,共7页Journal of Mining & Safety Engineering

基　　金：国家"十二五"科技支撑计划项目(2012BAK09B02-05)

摘　　要：针对某锡矿山缓斜极厚矿体采场采用高阶段、大直径深孔落矿分步骤回采过程中采空区上方切顶硐室的安全性问题,综合采用弹性力学理论和数值分析方法,研究了采场开采安全切顶厚度。在采用弹性力学方法提出了采场凿岩硐室长度为26 m,跨度为12 m,采场安全切顶厚度为6m的基础上,采用数值分析方法对采场安全切顶厚度进行了分析验证,并开展了切顶硐室表面位移及围岩应力的现场监测研究。研究表明:数值分析得出的最大拉应力值0.96 MPa小于抗拉强度,且安全率为2.98,最大位移监测值7.58 mm与数值分析值8 mm相近,故采场切顶厚度为6 m是合理的,可确保采场切顶作业过程的安全。研究成果已用于矿山生产实践,有效解决了该矿运用大直径深孔落矿开采缓倾斜极厚矿体时采场切顶硐室的安全性问题。In this paper,in view of the safety problems of the roof cutting chamber above goaf during ore extraction process step by step,by using high-level,large-diameter and deep boreholes in the stope of gently inclined and extremely thick ore body in one tin mine,the safety thickness of roof cutting in stope mining was studied based on elastic mechanics theory and numerical analysis method.According to elasticity mechanics,the length and span of drilling chamber in slope were confirmed as 26 m and 12 m,and the safety thickness of roof cutting was determined as 6 m.On this basis,the roof cutting thickness was analyzed and verified by numerical analysis,and the field monitoring including the surface displacement and surrounding rock stress of roof cutting chamber was also conducted.The results show that the maximum tensile stress value obtained from numerical analysis is 0.96 MPa,which is less than the tensile strength and the safety rate is 2.98,while the maximum displacement monitoring value is 7.58 mm,which is close to the numerical analysis value of 8 mm.Thus,the roof cutting in stope with 6 m in thickness is reasonable,which can ensure operation safety during roof cutting proces in the stope.The study results have been put into mining practices,and have effectively solved the safety problems of roof cutting chamber in the slope,when mining the gently inclined and extremely thick ore body in the tin mine by using ore extraction of large-diameter and deep boreholes.

关 键 词：缓斜极厚矿体 切顶厚度 弹性力学 数值分析 

分 类 号：TD856[矿业工程—金属矿开采]