Factors predictive of roof instability in addition to the existing CMRR criteria at two case study coal mines

This work uses two underground longwall coal mines located in the Western US (Mines A and B) as case studies to investigate which parameters are indicative of roof fall potential, and whether the Coal Mine Roof Rating (CMRR) is predictive of stability at these mines. Data were collected at 30 sites in each mine. These data sets included the CMRR, a record of the roof stability and a series of non-CMRR parameters thought to also be potentially...