Abstract Due to the severe strata pressure characteristic of the gob-side entry driving in the island mining face and the difficulty in supporting roadway,if supporting parameters of the gob-side entry driving are improperly designed,and roadway support fails,the mining safety will be greatly affected. Taking the return airway of No. 1251(3) island mining face as project background,3-dimensional fast Lagrange analysis of continua (FLAC3D) is adopted to study the distribution characteristics of advance abutment pressure in the island mining face. The mechanical model of main roof of the gob-side entry driving in the island mining face is established. By the mechanical model,the calculating formula of roof convergence affected by the dynamic pressure is derived. The study results show that when the advance abutment pressure of the island mining face increases obviously,the surrounding rock deformation of gob-side entry driving in the island mining face increases dramatically,which adds to the difficulty in supporting roadway. Based upon the above study results,the supporting parameters of roadway during the periods of roadway driving and mining are separately designed. The engineering practices show that the combining support of bolting,cable,wire mesh,and grouting can effectively control the surrounding rock deformation of the gob-side entry driving in the island mining face. The results can be generalized for roadway support under similar conditions.
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Received: 29 December 2010
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