Table B4.1a: Width-to-Thickness Ratios: Compression Elements Members Subjected to Axial Compression

Case: Unstiffened Elements Description of Element: (1) Flanges of rolled I-shaped sections (2) Plates projecting from rolled I-shaped sections (3) Outstanding legs of pairs of angles connected with continuous contact (4) Flanges of channels (5) Flanges of tees Width-to- Thickness Ratio: $b/t$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $0.56\sqrt{\frac{E}{F_{y}}}$ Examples: <empty>

Case: 2 Description of Element: (1) Flanges of built-up l-shaped sections (2) Plates or angle legs projecting from built-up l-shaped sections Width-to- Thickness Ratio: $b/t$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $0.64\sqrt{\frac{k_{c}E}{F_{y}}}$[a] Examples: <empty>

Case: 3 Description of Element: (1) Legs of single angles (2) Legs of double angles with separators (3) All other unstiffened elements Width-to- Thickness Ratio: $b/t$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $0.45\sqrt{\frac{E}{F_{y}}}$ Examples: <empty>

Case: 4 Description of Element: Stems of tees Width-to- Thickness Ratio: $d/t$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $0.75\sqrt{\frac{E}{F_{y}}}$ Examples: <empty>

Case: Stiffened Elements Description of Element: Webs of doubly symmetric rolled and built-up I-shaped sections and channels Width-to- Thickness Ratio: $h/t_{w}$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $1.49\sqrt{\frac{E}{F_{y}}}$ Examples: <empty>

Case: 6 Description of Element: Walls of rectangular HSS Width-to- Thickness Ratio: $b/t$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $1.40\sqrt{\frac{E}{F_{y}}}$ Examples: <empty>

Case: 7 Description of Element: Flange cover plates between lines of fasteners or welds Width-to- Thickness Ratio: $b/t$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $1.40\sqrt{\frac{E}{F_{y}}}$ Examples: <empty>

Case: 8 Description of Element: All other stiffened elements Width-to- Thickness Ratio: $b/t$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $1.49\sqrt{\frac{E}{F_{y}}}$ Examples: <empty>

Case: 9 Description of Element: Round HSS Width-to- Thickness Ratio: $D/t$ Limiting Width-to- Thickness Ratio $\lambda_{r}$ (nonslender/ slender): $0.11\frac{E}{F_{y}}$ Examples: <empty>

$E=\operatorname{modulus}$ of elasticity of steel $=29,000 \mathrm{ksi}(200000 \mathrm{MPa})$

$F_{y}=$ specified minimum yield stress, ksi (MPa)

[a] k_c = 4/√(h/t_w), but shall not be taken as less than 0.35 nor greater than 0.76 for calculation purposes.