ABSTRACT
The mechanics of deformation and failure of the roof and floor strata varies widely due to rock types and mining technology. Roof and floor strata stability is governed by the lithology of rocks and the structural defects, as listed below: Weak rock strata stability became an increasingly important element of mine stability, because it hinders mechanized and rapid mining techniques. Competent subcoal strata is essential for overall mine stability as well as for interaction with coal pillars and external support. The lithology of weak roof strata plays an important role, particularly with the aspect of reinforcement of the mine roof and its external support. The analyses of roof displacement of weak rock were approximated from the concept that a mine roof represents structures of the beams or plates, which are loaded vertically by the own weight, the weight of overlying strata.
