Use of distinct element models to investigate collapse and support of an underground opening as a function of varying rock mass quality.
MacLaughlin-MM; Brady-TM; Pakalnis-R
50 Years of Rock Mechanics - Landmarks and Future Challenges Proceedings of the 41st U.S. Rock Mechanics Symposium, Golden, CO, June 17-21, 2006, ARMA/USRMS 06-967. Yale DP, Holtz SC, Breeds C. Ozbay U, eds., Alexandria, VA: American Rock Mechanics Association, 2006 Jun; 1-12
Previous work using distinct element (UDEC) models to study failure modes surrounding an underground opening in rock masses of varying quality [1,2] demonstrated that the failure mode and extent of failure observed in the models were highly correlated with rock mass rating (RMR). The previous models were constructed with three different joint orientation combinations, three joint friction angles, four joint spacing values, and two degrees of rounding of block corners. The results, based on limited data (72 models), suggested a drastic difference in behavior between models with symmetric and asymmetric joint orientation conditions. The current study expands this work to include 12 additional joint orientation combinations, a much more robust data set of 360 models, and the combined results do not show the marked difference in behavior between symmetric and asymmetric joint sets, but do display good correlation with both RMR and Q values. The current study also incorporates a suite of models containing rockbolt supports; the results show that standard empirical design guidelines are generally adequate, although special accommodations should be made in cases with steeply dipping joints, and/or low friction angle.
Mining-industry; Underground-mining; Models; Computer-models; Geology; Rock-bursts; Rock-falls; Rock-mechanics
Yale-DP; Holtz-SC; Breeds-C; Ozbay-U
50 Years of Rock Mechanics - Landmarks and Future Challenges Proceedings of the 41st U.S. Rock Mechanics Symposium Colorado School of Mines, Golden, CO, June 17-21, 2006, ARMA/USRMS 06-967