In Swedge, you define two planes that represent the slope. These planes are the slope face and the upper ground surface.
Typical wedge geometry for Swedge analysis (Hoek & Bray, 1981)
1,2-Failure planes (2 intersecting joint sets)
3-Upper ground surface
H1-Slope height referred to plane 1
L-Distance of tension crack from crest, measured along the trace of plane 1
In the case of designing a single bench in an open pit mine, the upper ground surface is synonymous with the horizontal portion of the bench. So, in this case the bench width is really the upper ground surface width.
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