Answer:
First, you should check the direction in which the self-weight of the structural elements acts. You can also display the self-weight graphically using "Display Navigator" (see Image 01). It often happens that a user does not convert the data when switching the global Z‑axis in the calculation parameters, and then only adjusts the geometry. The self-weight acts in the wrong direction, and it is necessary to assign it a correct sign in the load case (see Image 02).
