Soil bearing pressure from seismic overturning

[apaulos15]

Hey guys,

I was wondering if any of you could help me out on a problem I've been stuck with. Say you have a continuous wall footing with two shearwall segments. Say the footing is 20' long, and you have a 5' long x 8' high shearwall on each end. The seismic force on this wall line is 5 kips. The overturning moment for each wall segment would be 20 kip-ft.

Is there any reference or equation that I can refer to to help me find the soil pressures? I have two overturning moments on each side of the footing. Normally, for a single wall segment, I would find my pressure from the single overturning moment and the weight of the footing. However, when multiple moments are introduced, I don't really know how to proceed. I know that for this example, I could just treat it as one overturning moment, but for my problem, the shear walls aren't the same lengths and aren't placed at each end of the footing (i.e. one is in the middle, and one is on the end).

-Ant

 

[msquared48]

I think you are getting into a beam on an elastic foundation analysis here.

Mike McCann, PE, SE (WA)

 

[oldestguy]

Double posting is frowned upon, especially when most of these rooms are viewed by us members anyhow.