A Review of Rock Mechanics Applications in Canadian Bedded Deposits
A. IGNATIEFF, Deputy Director, Mines Branch, Department of Energy, Mines and Resources, Ottawa, Canada.
A practical picture of the effects of stress and of the structural environment in an extraction area in a bedded deposit is described, and the main factors of ground control where principles of rock mechanics can be applied are discussed. Reference is made to early work in Europe, where systematic rock mechanics studies started in coal mines, as well as to the early work in the Canadian coal mines. During the past two decades, considerable theoretical and experimental knowledge, pursued both in the laboratory and in the field, has accumulated throughout the world, but the state of the science still does not permit application of substantiated theory such as is found in the design of above-ground structures, largely because of the complexity of the rocks. The mining engineer, as oppm1ed to the civil engineer, is constantly faced by exposures of new ground that is often subject to unpredictable discontinuities. However, the rationale already developed by rock mechanics principles and experimentation provides concepts and information t hat may be useful in selecting mining layouts. These concepts and existing measuring techniques can also assist ground control as mining progresses. Many of the bedded deposits, much as coals and evaporites, have pronounced deformation properties, and there are limitations in making stress measurements within short distances of mine openings or extraction areas. On the other hand, the measurement of movement of the hanging wall (roof) and footwall (floor) of roadways and extraction faces, as well as the sides of pillars, provides a most useful tool in assessing ground stability. This paper is to be regarded as a brief progress report with particular reference to Canadian applications of rock mechanics to bedded deposits.
Canadian Mining, longwall, Ottawa, rock mechanics, Western Canada, Extraction, Mine, Mines, mining, pillar, Pillars, Rock, Rocks