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
Ag : Gross cross-sectional area of member
Ae : Effective area
be : The effective width
c1, c2 : Effective width imperfection adjustment factor determined from Table E7.1
D : outside diameter of round HSS
Fcr : Critical stress
Fe : Elastic buckling stress determined according to Equation E3-4,
Fel : Eelastic local buckling stress determined according to Equation E7-5
Fy : Specified minimum yield stress of the type of steel being used,
K : Effective length factor
L: Laterally unbraced length of the member
Lc : Effective length of the member, (= KL)
Pn : Nominal compressive strength, kips (N)
r: Radius of gyration
λ: Width-to-thickness ratio for the element as defined in Section B4.1
λr : 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, Pn, 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, Ae, based on reduced effective widths, be, de or he.
Critical stress, Fcr, is determined by limit states of Flexural Buckling or Torsional and Flexural-Torsional Buckling.
When
When
TABLE E7.1 | |||
---|---|---|---|
Case | Slender Element | c1 | c2 |
(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, Ae, is determined as follows:
When
When