When to tie the S.O.G to FDN wall and when not to?
When to tie the S.O.G to FDN wall and when not to?
(OP)
I am curious as to when it would be necessary to dowel the S.O.G into foundation walls and when it is not entirely necessary. This is mainly for one-storey box type structures with grade beams or foundation walls in the perimeter. What about sidewalks? Do we treat that differently from the S.O.G?
Clansman
If a builder has built a house for a man and has not made his work sound, and the house which he has built has fallen down and so caused the death of the householder, that builder shall be put to death." Code of Hammurabi, c.2040 B.C.






RE: When to tie the S.O.G to FDN wall and when not to?
RE: When to tie the S.O.G to FDN wall and when not to?
It depends on site conditions.
If full compaction is not possible along the sides of grade beam or foundation walls, it is better to provide dowels and grade beam is designed to carry weight of about 3 ft(1 m) wide SOG.
Same applies for the sidewalk.
Sometimes dowels are avoided as in case of grade beam top elevation higher than SOG top elevation, to avoid bending of dowels and to avoid site hinderance until the slab is poured.
RE: When to tie the S.O.G to FDN wall and when not to?
A properly designed slab on grade does not need to be connected. Slabs and walls will always settle at differing rates. Let them move independently.
Dowel though openings to prevent trip hazzards at doors.
RE: When to tie the S.O.G to FDN wall and when not to?
I always connect the slab to slab diamonds of column bearing on spread footings, otherwise differential settlement can telegraph through the outline of the diamond. Usually I connect those via 2x2 shear key.
If an exterior slab bears on a substantial amount of fill and is aligned with the interior finish floor, i dowel that slab to the wall.
Eric McDonald, PE
McDonald Structural Engineering, PLLC