A single reinforced rectangular beam is $400$ mm wide. The effective depth of

the beam section is $560$ mm and its effective cover is $40$ mm $.$ The steel

reinforcement consists of $4$ MS $18$ mm diameter bars in the beam section. The

grade of concrete is M$20.$ Locate the neutral axis of the beam section.

In example $4,$ the bending moment at a transverse section of beam is $105$ kN $-$

m $.$ Determine the strains at the extreme fibre of concrete in compression and

steel bars provided as reinforcement in tension. Also determine the stress in

steel bars.

In example $5,$ the strain in concrete at the extreme fibre in compression ${}_{cu}$ is

$0\mathrm{.}00069$ and the tensile stress in bending in steel is $199\mathrm{.}55\frac{N}{m}{m}^2.$ Determine

the depth of neutral axis and the moment of resistance of the beam section.