Point loading on a slab

[WilsonEngineers]

I am looking for a calc to verify a (lightly loaded) post on a 4" slab but the spread footing design module in ClearCalcs requires 8" minimum as if a “footing”. The pier footing module allows a 4" thickness, but still says it fails overall without any individual item failing (that I see). This module also does not check punching shear.

For better or worse, thinner slabs commonly get point-loaded and it would be helpful to check bearing pressure and punching shear assuming no reinforcement without a prescribed minimum thickness.

[Ward_Engineering]

I read your post. Just FYi the CRC allows a load up to 750 lbs on a 3.5" slab per AH106.5. This is the max that I have used and can safely justify without a calc. Hope this helps.