Width-to-Thickness Ratios for IMF per AISC 341-16 with ideCAD

Description of Element

Width-to- Thickness Ratio

Limiting Width-to-Thickness Ratio

Example

λ_hd
Highly Ductile Members

λ_md
Moderately Ductile Members

Flanges of rolled or built-up I-shaped sections, channels and tees; legs of single angles or double-angle members with separators; outstanding legs of pairs of angles in continuous contact

b/t

Flanges of H-pile sections per Section D4

b/t

not applicable

Stems of tees

d/t

Walls of rectangular HSS used as diagonal braces

b/t

Flanges of boxed I-shaped sections

b/t

Side plates of boxed I-shaped sections and walls of built-up box shapes used as diagonal braces

h/t

Flanges of built up box shapes used as link beams

b/t

Webs of rolled or built-up I shaped sections and channels used as diagonal braces

h_w/t

Where used in beams or columns as flanges in uniform compression due to axial, flexure, or combined axial and flexure:

1. Walls of rectangular HSS

2. Flanges and side plates of boxed I-shaped sections, webs and flanges of built-up box shapes

b/t

h/t

Where used in beams, columns, or links, as webs in flexure, or combined axial and flexure:

1. Webs of rolled or built-up I shaped sections or channels [b]

2. Side plates of boxed I-shaped sections

3. Webs of built up box sections

h/t_w

h/t

h/t

For C_a ≤ 0.114

For C_a > 0.114

where

For C_a ≤ 0.114

For C_a > 0.114

where

Webs of built-up box sections used as EBF links

h/t

Webs of H-Pile sections

h/t_w

not applicable

Walls of round HSS

D/t