Brace Connection Connector Length Warning

Question

Hi all, 
 I'm designing a gusseted connection for a braced frame and cannot eliminate a warning: "Connector length less than allowable Table D3.1". The warning relates specifically to the interface of the gusset to the brace. From what I can discern from AISC design examples, the connector length should be defined by the center-to-center length of the outer bolts. I have increased this parameter to no avail and continue to get the warning. I tried reviewing the report with formulas and cannot find which parameter is not satisfying the requirements of Table D3.1 in the AISC steel manual. I have attached the report, with and without formulas. Unfortunately, Bentley isn't allowing me to upload the design file itself. Please see the google drive link below for the design file. I would really appreciate any kind of help determining what's wrong with my design. 
 
 drive.google.com/.../view 
 
 PDF PDF

Edgar Garcia-Hernandez · Answer

Dear Engineer ; 
 The model contains a gusset connection with a HSS brace in tension. In the tension rupture check for the brace, the shear lag parameter U is calculated as 1 -x/ l , where l = 1". In Table D3.1 of AISC 360-16, l is limited to the H (HSS width), which would be at least 5&rdquo; in this model. U= 1 should be used when l < H. 
 Table D3.1 does not address this condition so you will have to rely on your own engineering judgment to modify in the program somehow the length l . The following steel interchange addresses a possible approach that you could use for Case 6. The arrangement might also fall outside the scope of the Specification, and you decide how best to proceed, Read the next: http://msc.aisc.org/globalassets/modern-steel/steel-interchange/2014/032014_si.pdf Carlo Lini, P.E., LEED AP BD+C Staff Engineer American Institute of Steel Construction. 
 
 The best approach, I found to solve the issue was considering the next: 
 
 In the Connection Pad , go to Interfaces / Upper left brace 
 Change in the End connection type to another arrangement as Slotted or some other that allows you to modify the Weld length on brace 
 Chance the length to at least a value equal to the width of the HSS profile that you are using 
 Verify that as soon as you modify the length you can go back to the End connection type and use again the Tee 
 The model is corrected 
 
 Attached and image for better approach, Hopefully, this helps you on the solution.