8" Generator concrete pad on grade 1

[jdengos]

I always have a question for the slab on grade concrete pad design. It's not minor non important concrete pad that can ignore the frost depth by code.
Should I have a 2' thicken edge all around for the pad, or should I have 3'-6" deep edges all around so it's below frost depth.

I have seen 8" slab directly on grade without thicken edges, or 2' thicken edges, or 3'-6" thicken edges slab design. Which is proper?

Thanks

 

[jayrod12]

I am in a highly frost susceptible area. Generators that are capable of accommodating seasonal movement aren't provided with frost protected foundations. Similar for ground level mechanical units. If the mechanical guys can ensure that connections to the unit are capable of accommodating the expected movement, then we don't frost protect the foundations.

 

[r13]

Note coarser fill under the pad can reduce/eliminate frost heave potential.

 

[dik]

Can the equipment tolerate movement? if not, then piles, or insulation... Unless very heavy stuff... normally 5" or 6" slab and 12"x16" edge stiffeners in these environs... yes, and we have frost heave, too.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik