I have a BOEF spreadsheet program that I downloaded from the SEAOFSC.org website several years ago. I'm uncertain if I'm allowed to share it, although it's fully functional, and was obviously free to download at the time. The author is not identified in any way within the speadsheet. It references "Formulas for Stess and Strain" - Fifth Edition by Raymond R. Roark and Warren C. Young, McGraw-Hill Book Company (1975), pages 128 to 146.
It's a good spreadsheet, and I've used it on more than a few occasions for tank foundations, etc. If somebody can convince me it's OK, I'll post it.