Answer:
When using rotated surfaces in RFEM 6, make sure that the boundary line and the rotation axis do not cross each other. Otherwise, the rotated surface is incorrect and cannot be created.
One way to create the surface is to divide the boundary line at the point of intersection with the rotation axis. In the example shown here, the line of arch must be divided once in the middle.
After dividing the boundary line and correcting the input error, RFEM automatically creates the entered rotated surface.
