Rock mechanics research decreases longwall bump potential.
Barton TM; Campoli AA; Gauna M
1991 SME Annual Meeting, February 25-28, 1991, Denver, Colorado. Littleton, CO: Society for Mining, Metallurgy & Exploration, preprint 91-79 :1-6
Coal mine bumps, the violent failures of overstressed coal, present a safety hazard to miners when mining is conducted in deep, bump- prone coal mines. Two different longwall gate entry systems were evaluated in a southern Appalachian coal mine located in the Pocahontas No. 3 Coalbed under approximately 610 m of overburden which included a massive sandstone member. Both gate entry systems employed a center abutment pillar flanked by yield pillars. The original design employed a 24.2-M-square abutment pillar, while the new design employed a 36.6- By 54.9-M abutment pillar. Rock mechanics instrumentation data analysis and in-mine observations indicated that this increase in abutment pillar size significantly decreased bump potential. The new design in worse case conditions increased effective bearing area 62 pct with only a 9-pct increase in gate entry system width and eliminated face bumps that were experienced with the original gate entry design.
OP; Conference/Symposia Proceedings
1991 SME Annual Meeting, February 25-28, 1991, Denver, Colorado, preprint 91-79