Method of forming a rock cavity with a spherical rock cavity or partial spherical portion

摘要

The present invention relates to a method for excavating and preparation of rock cavities and then substantially spherical rock cavities or rock cavities having spherically shaped parts, such as dome-shaped ceilings, which rock cavities are intended as shelter, for the storage of solid or liquid products or for production plants in rock, whereby one drills a first series of radially outwardly extending holes (6) from a first distance (4) from one or more shafts/tunnels (3, 13, 14, 15, 16), preferably radially arranged from the centre of a sphere projected; that one drills a second series of radially outwardly extending holes (8) from a second, far more out arranged distance (7) from the centre, which holes (8) extend outside the holes of the first series; that one drills a third series of radially outwardly extending holes (10) from a third, further far more out arranged distance (9) from the centre, which holes (10) extend outside the holes (8) of the second series; that optionally further series of holes (12) are drilled from further far out situated distances (11) extending radially outwardly up to the boundaries of the cavity (1); that the first series of holes (6) are charged in their whole lengths; that each further series of holes (8, 10, 12) are charged in that part which lies outside a charging area of a previous series of holes (6, 8, 10) up to the touching point of a next series of holes (10, 12), whereby the charges will take consecutive annular charging areas, which cover the shape of the spherical cavity projected, and that blasting takes place of each annular area per se starting from outside in, or vice verse. IMAGE