estimation of equalibrim of forces?

[oyvinkle]

The forces that are retrived from the responsspectrum analysis. And can be displayed in the eg.( shear force diagrams) for building. They are the maximum responses that will ocure under the seismic excitation. Correct?

If so, how does the program calculate the needed capacity of the structure members when the time of the maximum responses are not known..as in a time history analysis. Eg. The combination of an axial load and a moment have both “god” and “bad” interaction. How does the program know that the right intraction will ocure?

May the answer lie in the combination rules used? When the combination rules are used. They estimate when the peak response that will occure from calculated modal responses. This is an estimate and then  a estimation will then lie upon the equalibrim of forces aswell?

Is this correct???  

[Artur.Kosakowski]

They are not maximal as you create quadratic combinations (they would be if they are combined in a linear way) so you may say that they are 'of values that are likely to happen in period of certain years'.

I would use signed quadratic combinations to running the design modules of Robot.

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