New and Existing Foundations in STAAD

[WYOPESE]

I have been asked to design a steel frame which is to be supported on new and existing pier foundations. If I know the existing pier capacity, what is the best way to model it in STAAD so that the support does not accept more load than the pier's capacity?

 

[canwesteng]

Not sure that this exists, or should exist in FEA for that matter. How are you rationalizing limiting the load on the pier? If the structure is statically indeterminate, I can see the argument that foundation failure = settlement, which lowers the stiffness of the support. Hand analysis would be the way to go in this case imo.

 

[DETstru]

I'm not a STAAD person and since I have to make some assumptions about your layout... I don't think you need to "tell" STAAD anything about your existing pier capacity.
I think you need to create a pier layout/geometry that distributes the load in a way that limits the load on the existing piers to whatever their capacity is. Not by plugging in a max load but by creating and tweaking the geometry that leads to that condition.

 

[WARose]

STAAD doesn't have a clue as to the capacity of pier. Like any other FEA program, it will distribute the load according to stiffness. Sounds like you are going to need a trial and error method. (Although I am not 100% sure what this situation is.)