STAAD Question

[spats]

I am trying to model the bending effects of self weight in a column section, subject to an initial deflection at mid-height, and doing a p-delta analysis. The initial deflection is required because otherwise, there would be no bending. Does anybody know how you would do this in STAAD?

 

[GalileoG]

Create a load case, go to the "nodal load" tab, select "support displacement" and viola.

 

[spats]

Clansman,

I must be doing something wrong, because when I do what you're telling me, I get a warning that says "support displacement in released direction ignored".

 

[Galambos]

This sounds like you need a second order analysis using an initial imperfection. The initial imperfection needs to be modelled by discretizing (splitting up) your column with nodes shifted from the axis and not performed with the support displacement command.

I could be wrong here, but STAAD only does first order analyses and the type of P-Delta analysis that it runs won't work in this situation as a second order analysis.

 

[mazingerz]

Staad.Pro is not the right app to use for a true 2nd order analysis. Better find others (eg. Oasys Gsa, etc..) The correct would be to form a geometric stiffness, aside from the normal structure stiffness.