Initia'...

$4.$ Consider the square column $(6in.x6in.),$ made of steel: $E=30,000$ksi,$S_y=30$ksi, and allowable bending stress, ${}_b=20$ksi, with an effective length $L_c=L=9ft.$ Determine the critical load, $F_{c,}$ for each Case below: Case $($a$)-$the centric load, $F$

$E=30,000$ksi

$S_y=30$ksi

$L_e=9ft=108in$

$\frac{L_c}{r}$

$\frac{L_e}{r}=\frac{108}{1\mathrm{.}7321}=62\mathrm{.}35$

$\frac{L_e}{r}$

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