Using A36 steel, determine the safe load P based on the capacity of the bottom strut with a cross section as shown. Use LRFD. Let k 1.0. C9x20 I 3.4m 4.5m 90mm a) Calculate the radius of gyration at strong axis of the built-up section. b) What is the critical slenderness ratio? c) Find the critical buckling stress. d) Compute the nominal capacity of the bottom strut. e) Determine the safe load P.

PROBLEM 2: The rigid frame shown is unbraced. The members are oriented so that bending is about the strong axis. Support conditions in the direction perpendicular to the plane of the frame are such that Ky = 1.0. The beams are W410 x 85, and the columns are B W250 x 149. A992 steel is used. The axial 4.5 m compressive dead load is 400 kN, and the axial compressive live load is 490 kN. a. Determine the axial compressive design strength of column AB. 5.5 m 6.0 m b. Determine the allowable axial compressive strength of column AB.

A compression member is built up from a W14x90 and a W10x49, both of A992 steel.a. Compute rx and ry for the built-up shape.b. Neglect flexural torsional buckling and compute the available strength for KxL = KyL = 30 feetusing LRFD.

The rigid frame shown is unbraced. The members are oriented so that bending is about the strong axis. Support conditions in the direction perpendicular to the plane of the frame are such that Ky = 1.0. The beams are W410 x 85, and the columns are W250 × 89. A992 steel is used, Fy=345 mPa. The axial compressive dead load is 750 kN and the axial compressive live load is 900 kN. Use the AISC alignment chart or Magdy I. Salama Formula for Kx. 4.5 m 5.5 m 6.0 m ly Cw Sx mm^2 mm^4 mm^3 1100 1510 A Ix rx Sy ry Zx Zy SECTION m mm^4 mm^3 378 mm^3 mm^3 mm^3 mm^9 1040 713 716 mm mm W250x89 4500 11400 143 W410x85 5500 10800 315 48.4 65.2 1230 574 1730 310 112 171 18 199 40.8 926 Which of the following best gives the axial strength of column AB? Use the NSCP 2015 LRFD specifications. O 2,340 kN 1,647 kN O 2,745 kN O 2,471 kN