回采空间变化对无底柱分段崩落法进路地压的影响  

Impact of Mining Space Variation on Stope Ground Pressure with Respect to Pillarless Sublevel Caving

作　　者：胡宝文[1] 李长洪[1,2] 魏晓明[1] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083 [2]金属矿山高效开采与安全教育部重点实验室,北京100083

出　　处：《金属矿山》2015年第12期5-9,共5页Metal Mine

基　　金："十二五"国家科技支撑计划项目(编号:2013BAB02B08)

摘　　要：以北洺河铁矿为工程背景,采用现场监测的方法,探究无底柱分段崩落法下进路地压随回采空间的变化规律。监测断面处的进路顶板、拱脚、及两帮处的径向受力随回采工作面的推进大致分为3个阶段：稳定阶段、承压阶段、卸压阶段。当监测断面与回采工作面的距离大于15排炮排间距时,进路围岩处于稳定状态,不受回采空间变化的影响。当监测断面与回采工作面的距离在5~15排炮排间距时,进路围岩处于承压阶段,且当回采工作面推进到5~10排炮排间距范围内,开始出现应力拐点,即岩体变形加剧,应力上升加快。当回采工作面推进到1~5排炮排间距范围内,径向受力处于来压峰值阶段,或处于来压峰值与卸压2个阶段。现场的钻孔取样结果表明,在距爆破工作面5 m以内,顶板深度2 m以内,岩体的损伤程度较高,完整性较差,这主要是爆破应力波与回采所引起的来压作用共同造成。研究结果为进路围岩的合理支护以及安全回采提供理论依据。By virtue of field monitoring method,the variation law of ground pressure of roadways with change of excavation working space was explored with respect to pillarless sublevel caving,with Beiminghe Iron Mine taken as the engineering background. The radial force of roof,arch springing,and sides of roadways can be divided into three phases with advance of working face,which are stabilization,pressure-bearing,and unloading stage. As the distance between monitoring section and working face was greater than 15 blasting row spacing,the surrounding rock of roadway was in stable state and uninfluenced by the variation of mining space. As the distance was from 5 to 15 blasting row spacing,the surrounding rock of roadway was in the pressure-bearing stage,and the inflection point of stress started to appear within variation from 5 to 10 blasting row spacing,which means that rock mass deformation was intensified and uplifting of stress was accelerated. The radial force would be closed to the peak or in the both stages of peak and post-peak within the variation from 1 to 5 row spacing. The damage degree of rock mass is higher and its intactness is lower within thickness of 2 meters and 5 meters from working face,which are mainly caused by blasting stress wave and stress increment resulting from excavation. The research results provide theoretical basis with reasonable supporting and safety mining.

关 键 词：无底柱分段崩落法 地压监测 回采空间 顶板损伤 

分 类 号：TD853[矿业工程—金属矿开采]