Safe development of the decorative jaspilites in the energetically disturbed massifs

Abstract

Investigations were conducted in the field of the development of the decorative jaspilites in the energetically disturbed zones of massifs based on the results of the analysis of the rock pressure energy manifestation around the underground workings. Physical essence of the phenomenon of zonal capsulation of the underground workings is revealed. Physical properties of the rocks and the new hypotheses about the rock pressure were analyzed considering the assessment of the degree of stability of the outcrops, detection of the regularities of their deformation and destruction, linking the ores and rocks extraction in time and space, identification of the structural elements parameters of the development systems, fixing methods and the corresponding types of the supports. The results of industrial, laboratory and theoretical researches on standard and developed methods were studied. The parameters of the structural elements of the adopted field development system are justified: the dimensions of the room fender chambers along the strike and fall of the rocks, the width of the room fender, the thickness of the inclined ceiling and intermediate mass, the number of the shrink stoping along the fall of ground and the strike of the rocks considering 15-fold safety factor. The economic estimation is given related to the proposed technology based on the lag of the second working on jaspilites from mining works on iron ore: the estimated profit for the mine is 8.6 million dollars per year. Additions were made to the current manuals. Stable parameters are recommended concerning the extraction blocks of the sub-chamber development system, with which the monoliths are extracted for the stone working industry in Ukraine, while the ratio of the prices of merchantable ore and large-block jaspilite is 1: 6.