Determination of dimensions of artificial pillars in the ascending two-stage chamber mining system

Abstract

In the practice of development of ore deposits of non-ferrous metals, combined development systems are increasingly used. The horizon is divided into chambers of stages I and II, which differ in the type of stowing material used. The chambers of stage I are filled with solid stowing, and the chambers of stage II are filled with loose rock. The economic performance of the development system is largely determined by the ratio of I and II stage chambers, since the costs of solid and loose rock stowing are significantly different. In this order of works, the following geomechanical situation takes place: in addition to rock pressure, which loads the pillar from the hanging wall, there is lateral pressure of loose rock deposit on the pillar, which is a retaining wall. The pressure tends to destroy, overturn or move the pillar. Thus, the purpose of this work is to determine the dimensions of monolithic pillar retaining walls in conditions of complex simultaneous loading by rock pressure and active pressure of loose rock deposit when changing technological parameters of development system. A calculation scheme for determining the dimensions of artificial pillars is made, modern methods of calculating rock pressure are described and the width of the retaining wall is calculated when changing the strength of the monolithic deposit and the dip angle of the deposit.