Fundamental Specifications for Steel Construction/Compression

Flexural Buckling

• $P_{n}=F_{n}A_{e}$

For $F_{y}/F_{e}\leq 2.25$

• $F_{n}=(0.658$^{($F_{y}/F_{e}$)})$F_{y}$

For $F_{y}/F_{e}>2.25$

• $F_{n}=0.877F_{e}$

Sections Not Subject to Torsional or Torsional-Flexural Buckling

• $F_{e}$ = π²E/(KL/r)²

Definitions

• $F_{c}r$ = flexural buckling stress (ksi, MPa)
• $F_{e}$ = elastick buckling stress (ksi, MPa)
• $F_{y}$ = specified minimum yield stress (ksi, MPa)
• $F_{u}$ = specified minimum tensile strength (ksi, MPa)
• $A_{g}$ = gross area of cross section (in², mm²)
• $A_{e}$ = effective net area of cross section, as reduced for holes and/or local buckling effects (in², mm²)