I am modelling a prestress concrete bridge using SOFISHA and beam elements. In order to model the cables referenced to the top section I am using: BEAM NP -1.
I have noticed that when using NP -1, the forces at the nodes are not applied at the gravity centrer (GC), but at the reference axis. Therefore, if a beam was an axial force, after a joint it will generate a moment as well (due to eccentricity).
I am attaching a teddy file with a simplify model, to see if anyone can corroborate this assumption.
The first example shows a beam modelled with NP-1, the reference axis is the top fiber.
Second example shows a beam model through its GC.
Third example shows a beam modelled without NP, but the reference axis is the top fiber.
MODELO_03_EStado_0_test2.dat (4.4 KB)