Seismic Design of Foundations in SCBF

[Kussro]

For a structure assigned to SDC "D" does the overstrength factor apply to the design of the foundations for the columns in a Special Concentric Braced Frame (SCBF)?

 

[JoshPlumSE]

I think it would apply to connections.... The classic example that I'm thinking of is the uplift connection between piles and pile caps. Non-ductile failure when it occurs, therefore, the connection needs the overstength factors. Other aspects of foundation design would probably be pretty ductile (soil bearing limits, slab or footing reinforcement).

 

[sandman21]

It depends on which code you are using, CBC-DSA, yes you will be required to use overstrength. If using IBC it's a little tricky, ask yourself do you consider the foundation a collector element? If yes then design for overstrength. I consider it a collector element and use overstrength.

 

[MrStohler]

If you are using IBC, it depends on your foundation system. Carefully review Chapter 18 of IBC for the sections relevant to the system you are using. Also consider the loads that will be imposed should the SCBF plastic mechanism is developed (yielding of the braces).