Slab on grade design
Slab on grade design
(OP)
I need help to design a slab on grade.
I have a one story commercial building (90'x150'), and most of the loads are on the perimeter of the foundation (point loads spaced at 15' on center). I just need to design for relatively small uniform load of 100 psf.
Will 4" slab work with crack control joints at 12' on center and with minimal reinforcing for temperature and shrinkage.
Also, the soil report indicates a maximum PI = 8. I have read some articles indicating that beam spacing should not exceed 20'. Do I need any beams since the area is big (13,500 SF) Does this apply only for slabs on plastic/compressible clay (with high PI)?
The soil is mostly sandy silt/silty sand.
I have a one story commercial building (90'x150'), and most of the loads are on the perimeter of the foundation (point loads spaced at 15' on center). I just need to design for relatively small uniform load of 100 psf.
Will 4" slab work with crack control joints at 12' on center and with minimal reinforcing for temperature and shrinkage.
Also, the soil report indicates a maximum PI = 8. I have read some articles indicating that beam spacing should not exceed 20'. Do I need any beams since the area is big (13,500 SF) Does this apply only for slabs on plastic/compressible clay (with high PI)?
The soil is mostly sandy silt/silty sand.





RE: Slab on grade design
RE: Slab on grade design
RE: Slab on grade design
Thanks a lot for your information because it is very helpful. Just one thing I would like to verify. When you say isolation from the slab, do you mean absolutely no dowels to tie the perimeter foundation with the slabs? Or just an isolation around each column? Thank you.
To jmiec,
The point loads are a result of the roof load spaced at 15' on center around the perimeter. Average point loads is about 15k.
RE: Slab on grade design
RE: Slab on grade design
RE: Slab on grade design