Numerical Modeling Applied to Simulating Cutter Roof Failure in Underground Coal Mines.
Proc 3rd Conf on Ground Control Problems in the Illinois Coal Basin 1990 :143-154
This paper presents an overview of the application by the U.S. Bureau of Mines of three unique numerical modeling techniques to analyze cutter roof problems in underground coal mines. Cutter roof failures are common in coal mines, where the immediate roof is often comprised of thin shale laminae exposed to high regional tectonic stress fields. The effects of various stress-control measures are simulated with finite-element model analyses to gain insight into their respective effects on reducing the high levels of shear stress at the entry corners. The application of the boundary-element method is demonstrated in evaluating the effectiveness of caving chambers or sacrificial entries to relieve the stress conditions initiating cutter roof failure. Application of the distinct-element method takes the analyses beyond the elastic continuum limits to simulate the propagation of a shear fracture and subsequent redistribution of stress within the mine roof. A simple roof bolt model was implemented to show the benefits of bolting to increase the resistance to shearing and separation along horizontal bedding planes and maintain roof stability.
Proc. 3rd Conf. on Ground Control Problems in the Illinois Coal Basin, 1990, PP. 143-154