Weird strain at the corners of the beam
Hello everyone, I'm modelling a beam of steel under pure bending. I considered the NL Structural Steel that Workbench offers me, but I changed the Tangent Modulus to 100 MPa (in order to have a material without hardening by plastic deformation).
I considered a 2D plane stress beam with symmetry, rectangular cross section (width 1 mm and height 10 mm) and a large of 100 mm.
I computed the moment which provocates yielding, obtaining the value of 4166 Nmm (M*).
In the other hand, I computed the moment which fully plastify the beam, obtaining a value of M** = 1.5 M* = 6250 Nmm.
My boundary conditions are the followings: Applied moment on the right edge of 6250 Nmm and a remote displacement with all DOF set to 0 and behaviour deformable at the symmetry line.
When load is fully applied, I get this result of normal stress in X direction:
This is true scale. I want to know why I get higher stresses at the edges and consequently, those larger deformations in the corners, making them look like horns.
Maybe I should just ignore that if I think in Saint Venant's principle, but I want to know why that happens because I get a similar behaviour in other simulation of this kind (with torsion instead of bending).