(Solved): A reinforced concrete cantilever retaining wall and base are both 300mm thick. The retained s ...

A reinforced concrete cantilever retaining wall and base are both $300\mathrm{mm}$ thick. The retained soil is $3500\mathrm{mm}$ in height, toe $=450\mathrm{mm}$, and heel $=1600\mathrm{mm}$. The backfill behind the wall is subjected to an imposed load surcharge of $2.5\mathrm{kN}/{\mathrm{m}}^2$. A geotechnical survey gave the following soil parameters: - Unit weight of soil $=19\mathrm{kN}/{\mathrm{m}}^3$ - Angle of internal friction $=30^{?}$ - Allowable bearing pressure $=200\mathrm{kPa}$. - Friction co-efficient $=0.5$ The retained soil(backfill) will be well-drained. Assume $\mathrm{fcu}=30\mathrm{MPa},\mathrm{fy}=450\mathrm{MPa}$, Y16 steel bars and the cover to reinforcement in the wall and base as $50\mathrm{mm}$. 2.1 Determine the factors of safety against overturning and sliding. 2.2 Calculate ground bearing pressure. 2.3 Determine the main flexural reinforcement steel for the stem of the wall.