Abstract:
The stress change and roof and floor movement of working face during mining is anlyzed based on similar simulation test. Working face mining could lead to mine earthquake in the range of more than 50 m above the face, the stress concentration rapidly increase in ahead of working face of 10 m.Because of weakening action of cutting roof roadway, the length of hanging goaf is reduced, and the coal stress ahead is effective decreased. With the decrease of distance between cutting roof roadways, the roof strata breaking step decreases correspondingly, however the stress would increase with too short distance. The reasonable distance between cutting roof roadways is 15 m to 30 m according to the comprehensive analysis.