f$\text{'}$c$$is $25$MPa, Span is $4$m

An elevated pedestrian walkway in Sydney is constructed using a rectangular reinforced concrete section $2\mathrm{.}5$ m wide, and $0\mathrm{.}18$ m thick, see structural scheme in Fig. $2.$ The slab is simply supported, and the effective span is determined by the last digit of your SID, see Table $1.$

The slab is doubly reinforced with $16$ bars D$500$N$12$ at the top and $20$ bars D$500$N$12$ at the bottom. The clear concrete cover to the reinforcing bars is $30$ mm $($note: there are no stirrups$).$ The slab is required to support the own weight $(25$ kN$/$m$3)$ and a live load of $4$ kPa is applied occasionally on or after $28$ days of age.

a$)$ Calculate the short$-$term and long$-$term loading applied to the structure. Justify carefully your choice of $\backslash$Psi s and $\backslash$Psi l$.$

In the following questions, you may assume $\backslash$Psi s$=1\mathrm{.}0$ and $\backslash$Psi l$=0.$ Using appropriate transformed section properties,

b$)$ Calculate the expected mid$-$span deflection of the slab immediately after loading the slab at $28$ days of age.

c$)$ Calculate the total long$-$term deflection of the slab in accordance with the simplified approach in AS $3600.$

d$)$ Does the short$-$term and long$-$term mid$-$span deflection comply with the deflection limits defined in AS$3600?$ If not, how could you revise the design?