2) A built-up steel column, consists of W 350 x 90 with two 14 mm thick plates welded to form a box section. The length is 5.0 m. Assume both ends are pinned connected. Properties of W350 x 90: bf =...

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Extracted text: 2) A built-up steel column, consists of W 350 x 90 with two 14 mm thick plates welded to form a box section. The length is 5.0 m. Assume both ends are pinned connected. Properties of W350 x 90: bf = 250 mm Ix = 266 x 106 mm4 ly = 44.54 x 106 mm4 A = 11,550 mm? tf = 16.4 mm d = 350 mm tw = 9.5 mm Fy = 250 MPa E = 200 GPa A) Using NSCP 2015, calculate the design axial load of the column in kN. B) Determine the allowable compressive stress (MPa) of the built-up column using NSCP 2001 C) Using NSCP 2015, calculate the allowable axial load of the column in kN.