Question $3$:

$(50$ Marks$)$

$($a$)$ Shown below in Figure $3$ is a section through a concrete column which is subject to an applied axial force $1125kN$ and applied bending moment $225kNm.$ The concrete strength, $f_{cu}=35\frac{N}{m}{m}^2.$

Determine a suitable arrangement of reinforcement to resist the applied loads. $(15$ Marks$)$