Evaluation of success probability in multiple seam room-and-pillar mining

Abstract

A complete evaluation of multiple seam mining potential for any coal property requires the analysis of historical data and the controlling mining conditions. The major problem affecting multiple seam mining is interaction between workings in the contiguous seams. The success or failure of multiple scam mining can be evaluated using statistical techniques. A computer-based stepwise multiple regression algorithm is used to develop an equation for predicting the probability of success in two seam-mining situations. The model provides a measure of risk involved in mining multiple seams. The data used to develop the model are from a historical record of attempted multiple seam mining in the Eastern United States. The variables significantly influencing success or failure of multiple seam mining are percent sandstone in the interburden, ratio of interburden thickness to lower seam thickness, time delay, interburden thickness, thickness of both seams, depth of cover to upper seam, columnated pillars, columnated entries and the leading seam. The model developed was found to be quite satisfactory as a predictor of the probability of success within the range for which it was developed.