Inco Limited

Wayne N Lidkea

Gregory R Baiden

Allan G Douglas

William A Manfred

Douglas E Goldsack

Gregory Robert Baiden

A method for excavating a tunnel rock face by drilling a pattern of lifter holes and line holes. The line holes ensure the grade or slope of the excavation meets specification while reducing the need for cleaning out the face. A longitudinal band of lifter holes is drilled into the tunnel face at an acute angle in relation to the substantially perpendicular reference axis emerging from the tunnel face. A series of line holes, disposed opposedly adjacent to the lifter holes, are drilled at a smaller acute angle. The lifter holes are drilled deeper than the line holes and they do not intersect. Explosives are loaded into the lifter holes. The line holes are expendable and encourage fracturing of the rock.

Method for excavating a tunnel rock face by drilling a pattern of lifter and line holes

Backfill for a mine contains a main component of conventional backfill material and a flow enhancing superfine material component mixed with the main component. The superfine material component may be a clay, for example, and has a particle size of less than 1 micron. The superfine component is present in an amount of about 0.5 to 1% by weight to best achieve improved flow without plugging in a pipeline.

Growing community of inventors

Lively, Canada

Wayne N Lidkea