Simple Slab Design Equations

[General-Eng]

Hello! I am not a geotech or structural eng, seeking guidance to some basic equations for a feasibility exercise before contracting a design firm. We need to look at outdoor reinforced concrete slabs for generators.

A prelim geotech assessment provided some basic parameters (PI, LL, recommended allowable bearing capacity) - can we estimate a depth and specification for structural fill?

Based on the weight/dead load also want to determine required compressive strength of concrete - is there an ACI equation for this to use with some conservative assumptions?

Reinforcement - based on the loading want to calculate rebar requirements (% steel, no. and spacing of bars)

Thank you!

 

[phamENG]

Are you looking to do an elevated concrete platform (to keep it out of a flood plane, for instance) or a slab on grade? What size generators? Are these home backups or are you looking to supply emergency power to a hospital or backup pumps for a nuclear reactor? Scale is important.

When you say a feasibility exercise, do you mean developing preliminary pricing? If so, you'd be better off looking for a unit price estimator for quantity of concrete. Though be warned - pricing is pretty screwy right now. I haven't seen anything on concrete prices, but I know wood commodity averages have tripled since Covid hit. Whatever you come with now is probably not going to be accurate, and even if it is it'll probably change by the time the contractor walks on site.

If by feasibility you really mean seeing if it's feasible, then I'd say the answer is yes - these are done all the time.

Sorry I can't answer your questions more directly - they're actually really broad and sort of cover a few semesters of an engineering degree.