wrong extrapolations from integration points in abaqus usdfld

[roya22]

Dear all,

I have written a usdfld subroutine to calculate Von-mises stress. The results obtained from the subroutine are exactly the same as those provided by abaqus (mises stress output). However, when it comes to nodes, I get wrong results in some elements. particularly in low stress regions (e.g. 5MPa instead of 1. Thus, I think there is a problem with extrapolating results from integration points to element nodes.
Does any one know what should I do?

Thank you in advanced

 

[FEA way]

Check the documentation section Abaqus/CAE --> Viewing results --> Selecting model data and analysis results to plot --> Selecting result options (chapters "Understanding how results are computed", "Understanding result value averaging" and "Controlling result averaging"). This way you should be able to find the difference in the extrapolation/averaging procedure.

 

[roya22]

Thank you a lot. I will read it carefully.

 

[roya22]

Sorry,

I checked the values before averaging but they were also not the same. In spite of the fact that the values at integration points are identical.

Do have any other ideas?