Proceedings of the 25th International Conference on Ground Control in Mining, August 1-3, 2006, Morgantown, West Virginia. Peng SS, Mark C, Finfinger GL, Tadolini S, Khair AW, Heasley KA, Luo Y, eds., Morgantown, WV: West Virginia University, 2006 Aug; :1-9
The Spokane Research Laboratory/NIOSH and the University of British Columbia (UBC) geomechanics group are focusing on the development of safe and cost-effective underground design guidelines for weak rock masses having an RMR in the range of 15% to 45%. Weak ground conditions, ground support, and mining methods used in several North American underground mines were observed. The RMR values were calculated to update both span design calculations and stability graphs, and a database on underhand mining methods was developed to reflect existing North American mining conditions. The immediate rock mass was also characterized and analyzed in terms of prevailing type of ground support, potential failure mechanisms, and rock behavior to define how existing design curves must be modified for weak rock mass. The current NIOSH research attempts to provide rock mechanics tools to assist a mine operator in making sound economic decisions that will also ensure a safe working environment.