I’ve been working on a rather large GH definition for a timber building for which I am using a custom material csv-file and custom trapezoid cross sections to represent the squared solid timber members. The model worked well when I specified the cross sections for each element group. The resulting utilization for shell and beam elements were well below 100%.
In a next step, I wanted to test if the structure could be optimized using the OptiCroSec component. This is now the part that is giving me a headache. I defined a range of cross sections for each element group that I fed into the OptiCroSec component and specified a “start cross section” that I fed into the Assemble Model component. Further, I limited the displacement and set the target max. utilization to 0.7 (70%). The OptiCroSec component is not returning any error and the resulting cross sections per element are the same or larger than the start values I defined. However, the utilization values are way above the target value of 70%, both in the Beam/ShellView component and the UtilizationOfElements component. There are larger cross sections available in the lists I defined.
What could be the cause for this? Any help would be greatly appreciated; I am attaching some screenshots for clarification.
Oh, and I am working with Karamba 1.3.2 for Rhino6. Thanks a lot!!