Development of Design Procedures for Long Slender Pillars
Design guidance for rib pillars, built from back analysed in situ coal tests and two dimensional modelling rather than empirical data, for rock engineers laying out high extraction panels.
by DP Roberts, JA Ryder & JN van der Merwe | March 2005
Numerical modelling produced upper and lower bound strength formulae for rib pillars, the lower bound covering weak roof and floor contacts. The formulae apply between width to height ratios of 0.5 and 2.5, with linear interpolation below that, and give conservative designs above 3. Adjustments were suggested where regular joint sets occur.
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