Governing Slenderness Ratio of Built-up Member

\frac{a}{r_{i}} = \frac{4.0 in}{0.108 in} = 37.0

\frac{3}{4} (\frac{L_{c}}{r_{o}}) = \frac{3}{4} (\frac{192 in}{2.529 in}) = 57.1 > 37.0 o . k .

a	Weld intervals
r_i	Radius of gyration of (1) plate
L_c	Unbraced length of the column = 16 ft = 192 in
r_o	Minimum radius of gyration of the reinforced section (r_z in RFEM)

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