Q$2.$ Retaining wall is used for a residential development project. Figure Q$2$ shows a $3$ I

high $($height measured from ground$)$ reinforced concrete cantilever retaining wall. Th

thickness of the wall and the base is $300$ mm $.$

Assume that:

Soil density is $18k\frac{N}{m^3}$

Soil bearing capacity is $170k\frac{N}{m^2}$

Characteristics strength of concrete, $f_{ck}=30\frac{N}{m}{m}^2$

Characteristics yield strength of bar, $f_{yk}=500\frac{N}{m}{m}^2$

Density of reinforced concrete $=25k\frac{N}{m^3}$

Nominal cover $=45mm$

Diameter of reinforcement bar $=12mm$

The calculated moment on the different parts of the retaining wall are given as below:

Wall : $76$ kNm per m length

Heel : $88$ kNm per $m$ length

Toe : $25$ kNm per $m$ length

$($a$)$ Explain the important of evaluating the Evaluate the stability of the retaining

wall against the overturning by considering the passive earth pressure.

$(5$ marks$)$

$($b$)$ Design the reinforcement required for the retaining structure that satisfies the

design code requirements.

$($i$)$ Wall

$($ii$)$ Heel

$($iii$)$ Toe

$(15$ marks$)$

$($c$)$ From your result in $($b$),$ sketch the reinforcement detailing for the retaining wall.

$(5$ marks$)$