Method of selective underground mining and stabilization of rock cavities

摘要

The invention relates to a method of underground mining mineral or preparation of rock cavities, in which method resulting hollow spaces can be refilled entirely or partially with temporarily stabilizing ice. The hollow space resulting from the mining is prepared in a first step for ice filling in that the geothermal heat content in the walls of the hollow space partially is removed, so that the walls assume a temperature below 0 C. In a second step water is supplied, possibly together with a reinforcing additive, in layers and intermittently to the hollow space while the supplied water together with the possibly added reinforcing agent is being cooled and frozen. In a third step the frozen ice body is maintained by removing the constantly inflowing geothermal energy during a time period deemed necessary for achieving the object. The cooling preferably is effected by artificially cooled air. The first step and the third step, however, can be abolished when the climatic conditions are such, that the rock about the hollow space is frozen to below the freezing point. The cooling air flows in a closed system which is entirely separated from the ventilation air.