Verification according to AISC 360-22 (LRFD, ASD)
Check for interaction of flexure and axial force
Required axial stress is provided by:
where: | A | - | area of cross section |
Available axial stress is provided by:
- For LRFD: Fca = Fy ϕ
- For ASD: Fca = Fy / Ω
where: | Fy | - | specified minimum yield stress |
ϕ | - | safety factor (LRFD) | |
Ω | - | resistance factor (ASD) |
Required flexural stress is provided by:
where: | S | - | elastic section modulus |
Available flexure stress is provided by:
- For LRFD: Fcbw = Fy ϕ
- For ASD: Fcbw = Fy / Ω
Value of utilization for interaction of flexure and axial force is calculated as:
Check for shear
The nominal shear strength of I or U-shape is provided by:
¨
where: | Fy | - | specified minimum yield stress of the type of the steel being used |
Aw | - | area of web, the overall depth times the web thickness dtw |
For webs of I-shaped members with:
where: | h | - | clear distance between flanges less the fillet at each flange |
tw | - | thickness of web | |
E | - | modulus of elasticity of steel |
then:
For all other I-shaped members and channels when:
where: | kv | - | web plate shear buckling coefficient = 5.34 |
h | - | for built-up welded sections, the clear distance between flanges |
then:
otherwise if:
then:
Shear strength of interior web panels is provided by:
when:
then:
otherwise if:
then:
otherwise if:
Nominal shear strength of round HSS shall be determined as:
where:
where: | D | - | outside diameter |
t | - | design wall thickness |
but:
Check for shear force is determined as:
- for LRFD: Q / (Vn ϕv ) ≤ 1.0
- for ASD: Q / (Vn / Ωv ) ≤ 1.0
State of plane stress check
Reference stress is provided by:
where: | σx | - | normal stress |
τ | - | shear stress |
Check for plane stress is provided due to this condition:
- For LRFD: σv / (Fy ϕ) ≤ 1.0
- For ASD: σv / (Fy / Ω) ≤ 1.0