Problem $4-$ Bolted Connections $(25$ marks$)$

The tension member is $L6\frac{1}{2}\frac{1}{2}$ with area $A=4\mathrm{.}5$

in ${?}^2$ and $\stackrel{}{x}=0\mathrm{.}829($from AlSC manual$)$ and is

connected with $1\mathrm{.}125-$inch$-$diameter, Group A bolts

to a $\frac{3}{8}-$inch$-$thick gusset plate. Both gusset plate

and tension member use A$36$ steel $(F_y=36$ksi

and $\{$:$F_u=58$ksi$).$ No slip is permitted. For the

bolts, threads are in the plane $(F_{nv}=54).$

$($a$)$ Determine the design strength by

investigating all possible failure modes $(20$

marks$).$

$($b$)$ Check if the member can resist a service dead of $20$kips and a live load of $60$kips $(5$ marks$).$