Vertical foundations are just like wide monopoles or flag poles for the most part. Octagonal or circular foundation where anchorage of the vessel is the only thing that's more complicated than doing a standard building column.
Horizontal vessels can be different. Usually just a simple rectangular foundation. But, the loading can into things like "slide plates" that allow for temperature expansion / contraction on one side. That means the side with the slide plate gets designed to a lower lateral load (static friction coefficient of slide plate * dead weight on that pier). The other pier needs to be checked for that same force, but also for full seismic and wind.
I'm probably leaving something out because it's been 20+ years since I worked on one. But, I think I cover the basics.
@JoshPlumSE specifically its vertical foundation.I have no experience in designing this one and my last encounter in foundation analysis was maybe 5 years ago.So I'm studying it again.Can you recommend some references or examples so that I can study and practice.Thanks for the help
HTURRAK's reference looks pretty darned good to me. At least as a place to start. The concept of converting an octagon into an "equivalent square" is pretty much the way we did it 20+ years ago when I did this a lot.
The one thing that I always feel isn't really spelled out is that the pedestal is generally NOT going to meet the 0.005 steel ratio we use for most other types of pedestals. This kind of a pedestal is more of a "mass concrete" that assists in force transfer between the Vessel / Anchors / Footing. You want to protect it from surface cracking and have it develop the anchorage.
