Longwall mining is one of the most acclaimed and widely used in underground method for coal extraction. The interaction of powered supports with the roof is the key issue in strata mechanics of longwall mining. Contro...Longwall mining is one of the most acclaimed and widely used in underground method for coal extraction. The interaction of powered supports with the roof is the key issue in strata mechanics of longwall mining. Controlled caving of rock mass is a prerequisite pro thriving exploitation of coal deposits by longwall retreat with caving technique and support resistance has evolved as the most promising and effective scientific tool to predict various aspects related to strata mechanics of such workings. Load density,height of caving block, distance of fractured zone ahead of the face, overhang of goaf and mechanical strength of the debris above and below the support base have been found to influence the magnitude of load on supports. Designing powered support has been attempted at the different countries in different methods. This paper reviews the mechanism of roof caving and the conventional approaches of caving behaviour and support resistance requirement in the context of major strata control experiences gained worldwide. The theoretical explanation of the mechanism of roof caving is still continuing with consistently improved understanding through growing field experiences in the larger domain of geo-mining conditions and state-of-art strata mechanics analysis and monitoring techniques.展开更多
According to the rock burst features occurred in the coal mass of roadway rib in one mine,the mechanics model of coal mass and roof structure system along the edge of goaf was founded to analyze the stress of roof roc...According to the rock burst features occurred in the coal mass of roadway rib in one mine,the mechanics model of coal mass and roof structure system along the edge of goaf was founded to analyze the stress of roof rock layer,so the subside curve of roof rock layer was deduced.Furthermore,the stability of coal and rock system were analyzed,the critical load and critical resistance zone were used to judge the danger degree of rock burst occurrence.The influence of coal mass strength,brittleness degree,coal seam thickness,roof thickness,suspending length,equivalent shear module on the critical load, critical resistance zone was confirmed.So the rock burst occurrence conditions of coal mass in roadway rib mainly depend on mining depth,coal seam thickness and hard roof and floor,which are decided by the above studies,and successfully applied in prediction and prevention of rock burst in this mine.展开更多
文摘Longwall mining is one of the most acclaimed and widely used in underground method for coal extraction. The interaction of powered supports with the roof is the key issue in strata mechanics of longwall mining. Controlled caving of rock mass is a prerequisite pro thriving exploitation of coal deposits by longwall retreat with caving technique and support resistance has evolved as the most promising and effective scientific tool to predict various aspects related to strata mechanics of such workings. Load density,height of caving block, distance of fractured zone ahead of the face, overhang of goaf and mechanical strength of the debris above and below the support base have been found to influence the magnitude of load on supports. Designing powered support has been attempted at the different countries in different methods. This paper reviews the mechanism of roof caving and the conventional approaches of caving behaviour and support resistance requirement in the context of major strata control experiences gained worldwide. The theoretical explanation of the mechanism of roof caving is still continuing with consistently improved understanding through growing field experiences in the larger domain of geo-mining conditions and state-of-art strata mechanics analysis and monitoring techniques.
基金the Natural Science Fund of Liaoning Province(20042176)
文摘According to the rock burst features occurred in the coal mass of roadway rib in one mine,the mechanics model of coal mass and roof structure system along the edge of goaf was founded to analyze the stress of roof rock layer,so the subside curve of roof rock layer was deduced.Furthermore,the stability of coal and rock system were analyzed,the critical load and critical resistance zone were used to judge the danger degree of rock burst occurrence.The influence of coal mass strength,brittleness degree,coal seam thickness,roof thickness,suspending length,equivalent shear module on the critical load, critical resistance zone was confirmed.So the rock burst occurrence conditions of coal mass in roadway rib mainly depend on mining depth,coal seam thickness and hard roof and floor,which are decided by the above studies,and successfully applied in prediction and prevention of rock burst in this mine.
