Answer:
The surface to the right in Image 01 is replaced by a moment in the area of the column because the surface is rigidly connected to the column (the surface itself has no line hinge). To exclude this moment, it is necessary to create an additional line hinge for the right surface, or provide the column with a member hinge.
Question
Why do I obtain a bending moment in the surface in the area of the column in my model, even though the surface has been provided with a line hinge?
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