supported by the National Natural Science Foundation of China (No.50874103);the National Basic Research Program of China (No.2010CB226805);the Natural Science Foundation of Jiangsu Province (No.BK2008135);by the Open Foundation of State Key Laboratory of Geomechanics and Deep Underground Engineering (No.SKLGDUEK0905)
The influence of an upper,mined coal seam on the stability of rock surrounding a roadway in a lower coal seam is examined.The technical problems of roadway control are discussed based on the geological conditions exis...