Geomechanics and Ground Control · Ground Control · 1 mark · Numerical answer
A 150 m wide flat longwall panel reaches critical subsidence at depth 200 m. For the same critical width-to-depth ratio, find the corresponding width at depth 300 m, in metres to one decimal.
The critical geometry fixes W/H = 150/200 = 0.75. At the new depth, W = 0.75×300 = 225.0 m. This similarity calculation assumes the same subsidence-angle/geological conditions; depth alone scales the critical panel width.
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