Hello Dr. Ackva,

sorry, of course I described that quite badly.  Regardless of the type of model (3D/shell), I have normal stresses in the cross-section of a clamped beam, which result quite generally from bending and tension/compression (normal in the sense of orthogonal to the section surface).  In my simple model, the x-direction is the longitudinal axis of the beam and only bending normal stresses occur.
In the meantime I have learned a little.
In the attachment you will find a result picture. On the left the solid geometry and on the right the shell. The shell stresses are shown on the top side and on the bottom side. I have shifted the geometries accordingly by half the thickness. But I am not yet satisfied with this, because I want a uniform scale without a jump at the transition. I thought I might have to create a new result vector for this, which contains e.g. only SIXX ???

Best regards,

Hansbau52