Question $6$

The cantilever retaining wall shown below is backfilled with granular material having a unit weight, of $19kN{m}^{-3}$ and an internal angle of friction, $,$ of $30.$ Assuming that the allowable bearing pressure of the soil is $120kN{m}^{-2},$ the coefficient of friction is $0\mathrm{.}4$ and the unit weight of reinforced concrete is $24kN{m}^{-3}.$

Calculate the following if the units are in $mm$ :

a$)$ Determine the factors of safety against sliding and overturning.

$(15$ marks$)$

b$)$ Calculate ground bearing pressures.

$(10$ marks$)$