The Article presents the method for the determination of a minimum permissible thickness of rock interstrata, with which it is permissible to apply the steel-polymer roof bolts upon undermining of a coal seam. The method is based on the results of investigations of behavior of roof layers above the productive working with using the deep datum marks.
The paper considers three basic schemes of roof failure above the face bottom of long-wall during mining operations covering the whole diversity of mechanisms of support-roof interaction. The relationships are given for the determination of required rated resistance of the powered support with reference to the schemes of roof failure.
The paper considers three basic schemes of roof failure above the face bottom of long-wall during mining operations covering the whole diversity of mechanisms of support-roof interaction. The model of interaction between the powered support and heavy roof is given as well as the calculated scheme for the determination of necessary rated resistance of roof.
It was established the reciprocal interaction of longwall advance velocity, mining depth and main roof thickness per a pace of its subsidence; the proper graphs have been constructed.
In caving of main roof rocks immediately overlaying the seam, a great amount of energy from elastic compression of rocks is released, in consequence of that the dynamic loading on the powered support takes place. Consideration is given to the influence of the support power parameters on the loading dynamics.
