Research of numerical simulation for prediction of rock burst region under the fully mechanized top-coal caving mining condition

I Abstract The greatest mining depth of 34 high seam of Yangcun coal mine in Yanzhou, mining district is 323m.Main roof of isolated island working face is sandstone whose thickness is 15m. Its coal body has tendentiousness of intensely occuring rock burst. It had rock burst in the same seam of the coal mine. This article used numerical simulation step by step excaving method and calculate work face of twain side entity coal without the regions of high stress whose stress concentration factor is bigger than 4; And when the working face that have a goaf advanced to the distance which is about less than square size slightly, the high stress region A whose stress concentration factor K=4.15 similar to 5.63 appeared in the 20m left side end of the working face which neighbour goaf. It had proved that slight rock burst happened during mining process. There are areas which coal body aside 20m along the cutoff which neighbour the larger goaf (the length of goaf is 300m)of isolated coal which have two goaf. Its stress concentration factor K=4.0.It is the high stress region D; The left end socket of incline direction and advancing direction =20m x 11 m is the high stress area B with K=4.69 similar to 7.07.The left side end contiguity the smaller goaf(the width of mining is 150m) of incline direction and advancing direction =20m x 12m is the high stress area C with K=4.67. A,B,C and D regions are the key area of preventing rock burst It can be recognized finally through stress monitor and the drillings. So numerical simulation is a effective method to determine the high stress region which may appeared rock burst before mining.