A rectangular beam of cross$-$section $12$ in $22$ in has a span of $30ft$ and

has fixed$-$fixed boundary conditions. The beam is subjected to a total

ultimate load $($including self weight$)$ of $w_u=6\mathrm{.}0ki\frac{p}{f}{t}^2.$

Design the reinforcement for the beam to withstand the load.

Take $f_c^{\text{'}}=4,000$ psi, $f_y=60,000$ psi.

Draw the cross$-$section and show the placement of reinforcement.

Hint: Design the reinforcement for positive bending at mid$-$span and

negative bending at supports. Choose the bar sizes such that

curtailment would be practically possible.