Background information:

A $22m$ high slope with a face angle of $60$ degrees has been excavated in the upper

saprolite slope containing residual weak rockmass. Below the slope is a $35m$ dual$-$lane

access ramp that will be used to mine an interim Pushback for a period of $3$ years. A

$20cm$ wide tension crack has opened behind the crest of the slope, and it is likely that

the slope is on the point of failure. The friction angle of the material is estimated to be

$30$ degrees, its density is $25k\frac{N}{m}3,$ and the position of the water table is shown on the

sketch of the slope. The rock contains no continuous joints dipping out of the face, and

the most likely type of failure mode is a progressive failure along a circular failure

surface over a period of $7$ days.

Figure $4$: Vertical Section Through a Rock Siope

NB: Various Data and Charts are provided in Appendix B & A for your reference

In all your calculations, state any other assumptions made, and submit all annotations

of figures, tables and drawings