$F_y=350$MPa and $F_u=450$MPa for both the column and the channels. The effective length with respect

to each axis is $4\mathrm{.}90m.$ Use LRFD

Compute the moment of inertia about the neutral $x-$axis in $m{m}^4.$ Ans.

Compute the moment of inertia about the neutral $y-$axis in $m{m}^4.$ Ans.

$x{10}^6(10\%)$

Compute the governing slenderness ration. Ans.

$(10\%)$

$x{10}^8(15\%)$

Compute the design compressive strength of the built$-$up shape in KN$.$ Ans.

Determine the $\%$ increase in the design compressive strength $($after the addition of channels$).$

Ans.

$(15\%)$