The rectangular R$/$C beam shown is reinforced for flexure with $4-$#$9$ bars placed in one layer.

The concrete compressive strength is $4500$ psi and the steel yield stress is $60$ ksi.

$1.$ Determine the balanced steel ratio, $\backslash$rho b and the corresponding balanced steel area, A sb

$2.$ Based on your answer in Question $1,$ will the given tension steel be yielding at the

strength limit state? Justify your answer.

$3.$ Determine the maximum and minimum steel areas allowed by the ACI $318-19$ code.

$4.$ Is the given reinforcement within the allowable limits set by ACI $318-19?$

$5.$ Determine the nominal flexural strength, M n

$6.$ Determine the design flexural strength, $\backslash$Phi Mn

$7.$ Draw the strain profile at the strength limit state $($show strain values at the outermost

concrete compressive fiber and at the centroid of the tension steel area, and the

depth of the neutral axis$)$

$18$

$19\mathrm{.}5$

As $=4-$#$9$

SECTION $2\mathrm{.}5$