Back analysis and performance of Block A long hole open stopes – Kanowna Belle Gold Mine

The damage-failure criteria for numerical stability analysis of underground excavations: A review

“…It was demonstrated that the onset of increased depth of failure for massive to moderately jointed rock mass (Fig. 6a), exhibit good correlation with an estimated Hoek-Brown strength envelope (Cepuritis et al, 2007). Moreover, it was shown by Cepuritis et al, (2007) that the depth of failure increases with increasing stress in the form of changing the stress path from monotonic loading and shear towards low confinement conditions.…”

“…6a), exhibit good correlation with an estimated Hoek-Brown strength envelope (Cepuritis et al, 2007). Moreover, it was shown by Cepuritis et al, (2007) that the depth of failure increases with increasing stress in the form of changing the stress path from monotonic loading and shear towards low confinement conditions. Plus, the rock mass falloff occurs under unloading conditions, near the region of rock mass damage initiation threshold.…”

“…However, for highly fractured rock masses (Fig. 6b), it was demonstrated that the depth of failure generally varies over a wider range of stress conditions (Cepuritis et al, 2007).…”

“…In this regard, Beck and Duplancic (2005) determined the stresses using a nonlinear stress analysis and defined the depth and volume of failure considering the calculated plastic strains (Villaescusa 2014). Similarly, Cepuritis et al (2007) used back analysis on the stope performance in Kanowna Belle Gold mine, with the purpose of quantifying the effect of induced stresses on the rock mass damage level. Subsequently, the obtained depth of failure contours was plotted in σ1 -σ3 space for two different rock mass qualities.…”

“…These semi-empirical indicators for the depth of failure could be integrated in numerical analyses tools to quantify the extent of rock mass damage and failure around underground excavations. The depth of failure as a stability indicating criterion, has been extensively employed in numerical stability analyses for different types of underground openings (Cepuritis et al, 2007;Ghasemi 2012;Abdellah et al, 2018;Oniyide and Idris 2019).…”