Using the assumptions presented in ACI code $22\mathrm{.}2$ and $21\mathrm{.}2\mathrm{.}2,$ select $A_s($exact area$)$ for

two beams. Each beam has the dimensions shown below. For beam A$,$ select $A_s$ such

that at the nominal moment capacity $M_n,{}_t=0\mathrm{.}005($tension$-$controlled limit$).$ For beam

B$,$ select $A_s$ such that at the nominal moment capacity $M_n,{}_t=0\mathrm{.}002($compression$-$

controlled limit$)$

Calculate the nominal moment capacity of each beam.

Based on ACI Code $22\mathrm{.}2,$ what are the values of strain at the extreme concrete

compression fiber, ${}_u,$ and the curvature, $,$ for each beam?

Using the procedures developed in class, develop M$-$ curves for beams A and $B.$ Use

${}_0=0\mathrm{.}002$

Based on the curves from Problem $4,$ what are $M_n,{}_t,{}_u,$ and $$ for each beam?

Compare the results from Problems $2$ and $3$ with the results from Problems $4$ and $5.$ How

accurate are the ACI procedures? How does each beam behave when loaded to failure?

$f_y=60$ksi

$f_c^{\text{'}}=4$ksi