... strata is in effect, the thinner strata have a maximum calculated cavity height about 1/4 the original stope span, 1/6 the original stope span in the case of thicker strata. This model also serves to identify beam action versus fully supported plate action. 1. INTRODUCTION Stratification of rock...

... adjustment factor for the empirical "Stability Graph", a technique for design of open stope dimensions and support. stope rockmass hangingwall geometry Reservoir Characterization strength analogue stability span reservoir geomechanics wedge Stability Graph cablebolt metals & mining...

.... This restriction .is required to explain the observed failure and it implies that the remaining roof may be near failure. I INTRODUCTION The Breakdown Mountain Room in Salamander Cave, near Bloomington, Indiana has a maximum span of 35 m. The progressive collapse of 12 m of horizontally bedded limestone roof has...

... ABSTRACT ABSTRACT: The empirical scaled span approach for assessing surface crown pillar stability has been in use for over a decade. In this time it has been widely applied for dimensioning new pillars and for assessing the stability of old, often abandoned crowns. Based on updated knowledge...

... Siltstone stability metals & mining knowledge management mechanism Highwall Mining Artificial Intelligence prediction span numerical model tensile strength pillar interface siltstone material roadway unsupported span voronoi mesh precedent experience maximum unsupported...

... stability analysis shallow stope rock mass case study metals & mining Thickness Ground Control span Surface Crown Pillar Rock Mechamcs, Aubertm, Hassam &Mitn (eds) ¸ 1996 Balkerna, Rotterdam. ISBN 90 5410 838 X Lessons learned from stability analysis of case studies of shallow stopes of hard...

... induced falls of ground need to be reduced. Design procedures to provide estimates of safe spans between pillars must take into account the variability in beam thickness encountered in the mines, rock strength, intensity and orientation of jointing, horizontal stresses in the hangingwall as well...

... method. The equation has returned factors of safety representative of the failed and unfailed cases. A numerical correlation between critical span and rock mass cohesion is presented, and the span and material strength limits are discussed for chimneying disintegration to occur. Numerical modelling can...