A rectangular beam section $230$ mm x $400$ mm overall depth is reinforced with $2$ nos. of $10$ mm

dia bars at the top, $3$ nos. of $16$ mm $$ bar at the bottom. It is subjected to working shear force

of $18$ kN$,$ as torsional moment of $1\mathrm{.}2$ kN$-$m and bending moment $18$ kN$-$m$.$ Check for torsion

reinforcement. Materials are Fe $415$ and M$20.$