A photoelastic study of the stresses around an underground opening and its support system

The stress conditions around openings in rock have long been of interest to the field of rock mechanics. The purpose of this investigation was to determine the stress distribution around an opening with a rib and wall-plate support system. A photoelastic model of the opening (a modified horse-shoe section) was loaded in the centrifuge to determine the effect of body loading. Both the tangential stress and the stress within the rock bench, due to the opening, were determined. The stress conditions within the bench were examined using simulated ribs and a loading frame. Application of the data is discussed, as well as the relative importance of the various stress concentrations. It is concluded that a zone of tensile stress within the rock bench is in the limiting factor in the design of this opening --Abstract, page ii