The Design of Shaft Steelwork Towers at Reef Intersection in Deep Mines

The extent of ground movements and stress concentrations in the vicinity of the reef in the deep mineshafts used in the South African gold mining industry have led to the requirement that special tower structures be developed to span the reef intersection zone in several new shafts. In order that structural engineers are able to design these towers, the dynamic behaviour of conveyances traversing them has been modelled to provide a means of determining the magnitude of the forces generated. This paper describes the design procedures arising from this analysis. An equation is derived which gives the minimum tower length and the minimum second moment of area that are required to ensure satisfactory operation of the shaft. Finally, an example of a typical tower design is given.

G.J. Krige