Negative Buckling Factors

[edferlac]

Hi all.

I'm triying to test the capabilities of bucking analysis of SAP2000.

Taking the "bag examples", see EXAMPLE 1-019 - 1 and related, I goal to the results as in the examples, by program and by manual calculation. The next step is try to apply to "real" case the buking analysis.

I started wich a very simple spatial frame, for industrial use (plane frame in XZ plane replicated 8 times along the YZ plane).

The space frame is a real build, since 1980 (it's stable, or I supose it!!!)

When I run the bucking analysis (only 2 vibration modes per analysis case), the program returns in some cases negative bucking factors, and I don't know interpretate it.

Somebody knows who it's negative factors represents?

Thanks.

 

[dozer]

It means your loads would have to be reversed in order to cause buckling in that mode.