The width-to-thickness ratios of steel elements are automatically controlled by ideCAD Structural according to Table D1.1.


Fy = Specified minimum yield stress
Ry = Ratio of the expected yield stress to the specified minimum yield stress, Fy
Rt = Ratio of the expected tensile strength to the specified minimum tensile strength, Fu
Pa = Required axial strength using ASD load combinations, kips (N)
Pu = Required axial strength using LRFD load combinations, kips (N)
Py = Axial yield strength , kips (N)
Ca = Ratio of required strength to available axial yield strength
E= Modulus of elasticity of steel = 29,000 ksi (200 000 MPa)

D1-1b. Width-to-Thickness Limitations of Steel and Composite Sections

The width-to-thickness ratios of compression elements should not exceed the limiting width-to-thickness ratios from Table D1.1, for members designated as moderately ductile or highly ductile members.