When I transfer data from idecad to sap2000, it creates a frame element with an embadded section above the curtains that I designed as a finite element. What is the reason for this?
Since the mathematical model of the shell elements in the finite element analysis in the SAP2000 program does not calculate the in-plane torsion (drilling DOF) realistically, it gives results that vary depending on the split frequency of the shell element mesh, especially in the tie beams connected to the walls from the rigid direction. In order to realistically model the behavior of the tie beams with the curtain, ideCAD extends the beam frame element into the curtain by some rigidity and provides the behavior together. The elements you see are fictitious elements created for this purpose. You can read the advice on the subject here:
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