Steel Members with Slender Elements per AISC 360-16 with ideCAD
How does ideCAD calculate steel compression strength with slender elements according to AISC 360-16?
The compression strength of steel elements is calculated automatically according to AISC 360-16.
The nominal compressive strength limit states of flexural buckling, torsional buckling, and flexural-torsional buckling are controlled automatically according to AISC 360-16.
Symbols
A_{g} : Gross cross-sectional area of member
A_{e} : Effective area
b_{e} : The effective width
c_{1}, c_{2} : Effective width imperfection adjustment factor determined from Table E7.1
D : outside diameter of round HSS
F_{cr} : Critical stress
F_{e} : Elastic buckling stress determined according to Equation E3-4,
F_{el} : Eelastic local buckling stress determined according to Equation E7-5
F_{y} : Specified minimum yield stress of the type of steel being used,
K : Effective length factor
L: Laterally unbraced length of the member
L_{c} : Effective length of the member, (= KL)
P_{n} : Nominal compressive strength, kips (N)
r: Radius of gyration
λ: Width-to-thickness ratio for the element as defined in Section B4.1
λ_{r} : Limiting width-to-thickness ratio as defined in Table B4.1a
Members with Slender Elements Excluding Round HSS §E7.1
This section applies to slender-element compression members.
The nominal compressive strength, P_{n}, is determined based on the limit states of flexural buckling, torsional buckling, and flexural-torsional buckling in interaction with local buckling.
Effective areas of the cross-section, A_{e}, based on reduced effective widths, b_{e}, d_{e} or h_{e}.
Critical stress, F_{cr}, is determined by limit states of Flexural Buckling or Torsional and Flexural-Torsional Buckling.
When
When
TABLE E7.1 | |||
---|---|---|---|
Case | Slender Element | c_{1} | c_{2} |
(a) | Stiffened elements except walls of square and rectangular HSS | 0.18 | 1.31 |
(b) | Walls of square and rectangular HSS | 0.20 | 1.38 |
(c) | All other elements | 0.22 | 1.49 |
Round HSS §E7.2
The effective area, A_{e}, is determined as follows:
When
When