Promising variants of systems for working thick deposits under conditions of high mine pressure

On the basis of prolonged study of the problem basic scientific principles were formulated for constructing highly effective systems for working thick deposits under conditions of high mine pressure. By using these assumptions a variant has been developed for rock-burst hazardless technology applied to thick areas of the Khibinsk deposits which is intended for preparing a block of haulage and trench levels; drilling of holes for breaking the work mass is accomplished from workings of the overlying haulage levels. This variant makes it possible to increase significantly the intensity of extraction and the technical and economic incices of underground mining in the development of thick deposits.