SAFER MINE LAYOUTS FOR UNDERGROUND STONE MINES SUBJECTED TO EXCESSIVE LEVELS OF HORIZONTAL STRESS

摘要

Excessive levels of horizontal stresses causernground fall hazards in underground mines in thernAppalachian Basin. At an underground stone minernin Pennsylvania, a modified stress control minernlayout is reducing the hazardous conditionsrnassociated with excessive horizontal stresses. Arnmicroseismic monitoring system is in place tornmeasure levels of rock stability and providerninformation on the effectiveness of the designrntechnique. The microseismic data is supplementedrnwith frequent and extensive mapping of roof fallsrnand roof rock damage. Findings to date show thatrnthe stress control layout provides more stablernconditions and thus a safer environment for the minernworkers.