CE $453$ Reinforced Concrete

Homework $3-$ Flexural Analysis and Design

Problem $6$: The rectangular beam shown in Fig. PS$-4$ carries its own dead load $($you must

guess values for $b$ and $h)$ plus an additional uniform dead load of $0\mathrm{.}5kj\frac{p}{f}t$ and a uniform

live load of $1\mathrm{.}5ki\frac{p}{f}t.$ The dead load acts on the entire beam, of course, but the live load

can act on parts of the span. Three possible loading cases are shown in Fig. P$5-4,$

$($a$)$ Draw factored bending$-$moment diagrams for the three loading cases shown and

superimpose them to draw a bending$-$moment envelope.

$($b$)$ Design a rectangular beam section for the maximum positive bending moment between

the supports, selecting $b,d,$ h$,$ and the reinforcing bars. Use the procedure in Section $5-3$

for the design of beam sections where the dimensions are unknown. Use $f{c}^{\text{'}}=5000$ psi and

$fy=60$ksi.

$($c$)$ Starting with the beam section from part $($b$)$ use the procedure for design of tension

reinforcement when section dimensions are known to design flexural reinforcement for the

maximum negative moment over the roller support.

$($b$)$

$($c$)$