Steel brace section dimensions do not conform to WidthtoThickness Ratios.
This message is created by specifying the element name and floor on which it is located at the beginning of the report.
For example,
SBR001 BASE STORY Section dimensions do not conform to WidthtoThickness Ratios.
Widthtothickness ratios of highly ductile and moderately ductile braces are checked per AISC 34116 Table D1.1 and TBDY Chapter 9. Limit values of Widthtothickness ratios λ _{hd} or λ _{md} are given in AISC 34116 Table D1.1.
For detailed information, you can review the titles below.
Concentrically Braced Frames (CBF) per AISC 34116 §F
Solutions:
The crosssection of the steel element whose name and floor are given can be changed.
Steel beam crosssection selection can be made to reduce the header width/thickness or body height/thickness ratio.
If possible, a moderate ductility level can be selected.
AISC 34116 Table D1.1 is given below.
Limiting WidthtoThickness Ratios for Compression Elements for Moderately Ductile and Highly Ductile Members  

Description of Element  Widthto Thickness Ratio  Limiting WidthtoThickness Ratio  Example  
λ_{hd}  λ_{md}  
Flanges of rolled or builtup Ishaped sections, channels and tees; legs of single angles or doubleangle members with separators; outstanding legs of pairs of angles in continuous contact  b/t 

 
Flanges of Hpile 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 Ishaped sections  b/t 

 
Side plates of boxed Ishaped sections and walls of builtup box shapes used as diagonal braces  h/t 

 
Flanges of built up box shapes used as link beams  b/t 

 
Webs of rolled or builtup 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:
 b/t h/t 

 
Where used in beams, columns, or links, as webs in flexure, or combined axial and flexure:
 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 builtup box sections used as EBF links  h/t 

 
Webs of HPile sections  h/t_{w}  not applicable 
 
Walls of round HSS  D/t 


Symbols
λ_{hd} : Limiting slenderness parameter for highly ductile elements
λ_{md} : Limiting slenderness parameter for moderately ductile elements
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