Sub-level caving with bottom ore drawing has gained wide acceptance in
rich, soft, low magnetic iron ores because it provides moderate ore
dilution and ore losses. The main problem here is the high rock pressure exerted on sub-level
drives situated in the sub-level sill pillars. To reduce this effect, the ore
block is divided into panels. This paper illustraes the method of
determining the maximum panel width providing low maintenance cost of
sub-level drives.