Local thickening of a slab on grade
Local thickening of a slab on grade
(OP)
Hello, I havent done this before so Im asking for some guidance and suggestions.
When Im dealing with slabs on grade I choose thickness (ussually 250 mm thick for residental structures) and this is sufficient most of the time.
But in this case Im dealing with large single loads (from columns) that are acting on a slab on grade so shear breakthrough - punching shear is a problem.
Is it allright to locally increase thickness of a slab as shown in view a-a in attached image?
Should I reinforce this thickened part as a spread footing?
Is this expensive to do in a field?

When Im dealing with slabs on grade I choose thickness (ussually 250 mm thick for residental structures) and this is sufficient most of the time.
But in this case Im dealing with large single loads (from columns) that are acting on a slab on grade so shear breakthrough - punching shear is a problem.
Is it allright to locally increase thickness of a slab as shown in view a-a in attached image?
Should I reinforce this thickened part as a spread footing?
Is this expensive to do in a field?







RE: Local thickening of a slab on grade
Yes
I would.
No
Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
https://www.facebook.com/AmericanConcrete/
RE: Local thickening of a slab on grade
RE: Local thickening of a slab on grade
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RE: Local thickening of a slab on grade
RE: Local thickening of a slab on grade
The walls and/or columns are then separated by expansion joint material to allow the footings to settle somewhat independently from the slab.
However, I say "somewhat" because if a footing settles, the earth under it and adjacent to it will also be affected by that settlement and the slab may still settle down as well.
The slab cracking would just be less severe.
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