Answer:
Objects like lines and nodes are automatically integrated in a surface by default, as soon as these objects have a static function (for example, supports, load reference). Objects that are not statically relevant are not automatically integrated in the surface.
The reason is as follows: The results are not averaged at integrated lines, thus often leading to a jump in the color distribution of the result values. At statically relevant lines, this is also correct. However, some integrated lines are just construction lines, which are imported mainly when DFX files are imported.
If you select the "Integrate unutilized objects in the surface" check box in the FE Mesh Settings dialog box (see the image), all lines will be integrated in the surface.
