801x
000328
2017-12-01

Question

The result combinations calculated in RSTAB include the minimum and maximum values as well as the corresponding internal forces. Why are these internal forces not considered in KAPPA? Which internal forces are used in KAPPA to perform the design?


Answer:

In the case of Design Method 1, RF‑/KAPPA uses the internal forces My and Mz at the respective design location. If the maximum values of My and Mz occur at different locations on the member, the corresponding internal forces may be applied. This is ensured by the design at different x-locations.

In contrast, the Design Method 2 always applies the maximum values of the moments over the entire member length, even if they do not occur at the same location on the member. Therefore, the component from bending is always constant for the entire member or continuous member in the design criteria.

The moment factor βm for determining the shape of the bending moments My and Mz is always applied with 1.1 or 1.0 (depending on the design method) for a result combination. The result combination represents an envelope from which the shape of the moment factor cannot be clearly determined.


Author

Mr. Vogl creates and maintains the technical documentation.