Mechanism and Control Scheme of Rib Falling for Large Mining Height Full-seam Mining

In Wangzhuang Coal Mine of Lu'an Group Corporation, the mining method of 8101 mining working face is large mining height full-seam mining and the phenomenon of rib spalling in the process is serious. We analyze the mechanism of rib spalling and propose the terraced mining method to control it. The finite difference software FLAC^3D is used to simulate the influence of various parameters of the terraced coal wall on the stress distribution at working face. The results show that if the working face is the 1.2 m width and the ratio of the upper and down side in the stage is 5 to 4, the shear stress of working face coal wall decreases greatly, the stress status is greatly improved. Through the observation and statistics in practice, we got that the problem of rib spalling is obviously not as serious as before after using terraced coal advancing.