Pillar design in hard brittle rocks

A common mining practice involves leaving rock "pillars" between mine openings to maintain the stability of the openings. A great deal of work has been done on the stability of coal pillars however, relatively little work has been done on the stability of hard-rock pillars. The work that has been done on hard-rock pillars is based on empirical studies, and most of the pillars in these empirical studies are rib pillars. The problem with empirical studies is that they are generally site specific and pillar failures must occur before an empirical strength curve can be calibrated to a particular mine site. This thesis presents a theoretical framework for assessing the stability of hard-rock mine pillars using rock mass strength and numerical modelling. The framework is based on the concept that the strength of hard brittle rocks is fundamentally controlled by a "cohesion loss" process. (Abstract shortened by UMI.).