The 25-ft-long HSS6 4 1/8 (see Appendix B for its cross-sectional properties) column shown in Figure P16.55/56 is fi xed at base A with respect to bending about both the strong and weak axes of the...

The 25-ft-long HSS6

4

1/8 (see Appendix B for its cross-sectional properties) column shown in Figure P16.55/56 is fi xed at base A with respect to bending about both the strong and weak axes of the HSS cross section. At upper end B, the column is restrained against rotation and translation in the x–z plane (i.e., bending about the weak axis), and it is restrained against translation in the x–y plane (i.e., free to rotate about the strong axis). Use the AISC equations to determine the allowable axial load Pallow that may be supported by the column, on the basis of

(a) buckling in the x–y plane.

(b) buckling in the x–z plane.

Assume that E = 29,000 ksi and

_Y
= 46 ksi.