Numerical Simulation of thick overburden and coal seam water conservation mining

Based on the analysis of the geological data from Yushuwan Coal Mining,which is of a typical thick overburden and shallow coal seam situation,this study conducted numerical simulations by using RFPA-a rock failure process analysis software.The results of the simulation are 31m for the height of the caving zone,90m for the height of fractured zone and about 35m of bending sinking zone.This study shows that movement of the overburden caused by mining is similar to that of conventional coal mine,and the three-with-one phenomenon that comes with the overburden of shallow seam did not occur in this study.With the empirical formula,the calculated height of water flowing fractured zone is between 70m and100m,and the fractured zone did not reach the aquifer.The study concludes that the thick overburden and coal seams can achieve the objective of underwater coal mining.