Method of protection and maintenance of capital sectional mine workings at great depths

Abstract

The experience of mine workings maintenance shows that their normal operational condition during the whole service life can be provided only by using the bearing capacity of the rock mass containing the mine workings. This requires the use of non-traditional types of support, which would have a significant carrying capacity, low material and labor intensity of erection, be amenable to a high degree of mechanization, as well as actively influence the stress-strain state of the massif in order to involve it in the joint work. During the excavation movement a zone of inelastic deformations develops in its vicinity, the rock loosens and increases in volume, which puts additional loads on the support of the excavation. It is possible to reduce the time of this zone development by accelerated formation around the excavation at a given distance from it of the contour of the unloading zone with minimal deformations, which ensures the transfer of increased stresses from the excavation contour deep into the massif. In this case the undisturbed contour massif, reinforced with anchors, plays the role of the shield.