ABSTRACT
The real characteristics of the ‘support-lateral rocks’ system usually differ notably from those of the supports themselves. Their distortion is due to empty spaces and packing between the supports and the side walls, collapse of weak rocks at the points of contact with the supports, bending of supports towards the side walls, ‘shifting’ of the legs of the supports etc. In most geomining conditions the ultimate values of displacement of the rocks at the contour of working and load on the supports are governed by the characteristics of the latter. Supports of constant resistance are still not extensively used in drifts. The depth of mining, the compressive strength of the rocks, size of the mine working and types of models of supports were varied.
