Failure of rock mass in deep underground excavations could be attributed to a broad range
of performance malfunction, from plastic yielding of rock, generation of macro cracks on the
boundary of the excavation, gravity driven rockfalls or even complete stress-induced
collapse. The failure criteria determine the stress level (or strain level) at which the rock
mass loses its load-carrying (or strain-carrying) capacity. Determination of the state of
underground stability can be successfully achieved through implementation of appropriate …