Sherescistar

columns

The beam is supported on two columns.

$17.$ What is the effective length for column $BD?$

$(5)$

a$.KL=216$ in

$($b$.)KL=151$ in

c$.KL=144$ in

d$.KL=288$ in

$18.$ Choose the lightest square steel HSS section for column BD so that it has a radius of gyration that leads to a slenderness ratio $(K\frac{L}{r})$ smaller than $100$

$(10)$

a$.HSS33\frac{1}{6}$

b$.$ HSS $\frac{21}{2}\frac{21}{2}3$

c$.$ HSS $22\frac{1}{4}$ HSS $44\frac{1}{6}$

$19.$ Calculate the maximum load that steel column $BD$ can resist before it crushes $(10)$

a$.N$ max, $c=377\mathrm{.}5kjps$

b$.$ Nmax, $c=442\mathrm{.}5$kips

c$.$ Nmax, $c=267\mathrm{.}5$kips

d$.$ Nmax,$c=847\mathrm{.}5$kips

$20.$ Calculate the maximum load that steel column BD can resist before it buckles $(15)$

a$.$ Nmax, crit $=4$kips

b$.$ Nmax, crit $=96$kips

c$.$ Nmax, crit $=121$kips

d$.$ Nmax, crit $=55$kips

$21.$ Calculate the utilization of column $BD$ for the load applied to it$,R_B$

a$.105$

b$.0\mathrm{.}95$

c$.0\mathrm{.}14$

d$.7\mathrm{.}1$

Answers $17$ and $18$ are already answered, so please just answer $19,20,21.$