Relevant max stress in element contradicting

Grasshopper Karamba3D
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July_23.gh (81.2 KB)
Karamba: Relevant max stress in elements contradicting

Trying to compare Karamba with a parallel study by KTH (Tech Univ, Stockholm) who are using ANSYS Mechanical with same perimeters:

The Utilization of Elements/sig-max and sig-min come out fairly similar, typically around 20-24 MPa as expected. So does max displacement, 6-8 mm roughly.

More trouble to understand Beam Resultant Forces/Normal Force extracting to 16.5 and -2.4 kN at extremes. When divided with the cross section (Bamboo culm dia 10 cm with inner void dia 8.5 cm = 40cm2) to get the stress it’s way too low. I´m probably doing something fundamentally wrong here?

Another challenge is to learn von Mises stress concept used in ANSYS. In a way more useful as it combines all sigs and taus to get the final stress relevant for evaluation. Karamba has a bit of this multi-stress concept showing red and blue on the same element.

Sorry, gh-file is messy with many add-ons; some people cannot open it. Thanks for your patience, Ingemar

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hallo @ingemar,
the ‘Resultant Section Forces’-component returns the nomal force N encountered along the beam axis whose value represents the absolute maximum (see here).
Maybe you have to increase the number of results along the beam axis which are to be checked (see ‘NRes’).
In case this does not work: try to reduce the complexity of your definition and apply the divide and conquer strategy.
– Clemens