How does Prokon calculate imperfection moments in slender columns?

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Prokon calculates imperfection moments in slender columns differently for each axis due to the column's asymmetric slenderness, resulting in varying values for the x-axis and y-axis. In the discussed example, the x-axis imperfection moment is 0.85 kNm, while the y-axis is significantly higher at 4.41 kNm. This discrepancy raises questions about the expected uniformity of imperfection moments across axes. Users are encouraged to consult the design standards referenced by Prokon to understand the calculations better. Understanding these principles is crucial for accurate column design in engineering applications.
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Homework Statement:: Anyone familiar with prokon column design ? I have no idea how the program caluculate the imperfection moment in the slender column (braced/unbraced...
Relevant Equations:: I have attached an example here , it's an unbraced slender column here. Why the imperfection moment about y-axis and y-axis arent the same ? X axis imperfection moment = 0.85kNm, while the y-axis imperfection moment is 4.41kNm,

[Mentor Note -- thread moved from the schoolwork forums to ME since it is a general question]

I think it's wrong, imperfection moment should be the same for both axis , at intermediate height, top , bottom of column, correct me if I am wrong. ...

https://we.tl/t-Fw9Tvf8fhL
 
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dccd said:
Homework Statement:: Anyone familiar with prokon column design ? I have no idea how the program caluculate the imperfection moment in the slender column (braced/unbraced...
Relevant Equations:: I have attached an example here , it's an unbraced slender column here. Why the imperfection moment about y-axis and y-axis arent the same ? X axis imperfection moment = 0.85kNm, while the y-axis imperfection moment is 4.41kNm,

I think it's wrong, imperfection moment should be the same for both axis , at intermediate height, top , bottom of column, correct me if I am wrong. ...

https://we.tl/t-Fw9Tvf8fhL
Can you just attach a PDF of that file? (Click "Attach files" below the Edit window) I'm getting strange notifications when I try to click on that link. Thanks.
 
berkeman said:
Can you just attach a PDF of that file? (Click "Attach files" below the Edit window) I'm getting strange notifications when I try to click on that link. Thanks.

Here you go ..The uploading speed was extremely slow when I was trying to upload the file.
 

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dccd said:
X axis imperfection moment = 0.85kNm, while the y-axis imperfection moment is 4.41kNm,
Because the column is rectangular, the slenderness is asymmetric, and so the imperfection moment is asymmetric.
 
Baluncore said:
Because the column is rectangular, the slenderness is asymmetric, and so the imperfection moment is asymmetric.
Do you know how to get the exact value
?
 
dccd said:
Do you know how to get the exact value ?
The Prokon design software must reference the standards and design rules it follows.
You should look for the design references on which the Prokon software is based.
 
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