2022x
003192
2019-06-19

Question

In some areas of the modeled downstand beams or ribs, there are also walls or pilasters. Is it necessary to separate and remove the downstand beams on the walls, or should they continue through them?


Answer:
When modeling a structure, you should avoid areas with double stiffnesses. If you model a downstand beam and a wall at the same location, these elements split the load application. The disadvantage of separating the members on the wall perimeter is that singularities occur at this location. Moreover, the area of the load application from the rib to the wall is at the ceiling height.
Thus, there is no ideal solution in this combined modeling from members and surfaces.
In the case of small models, it would be possible to model the downstand beams and carry out the design by means of result beams.