Basement Wall Top Restraint
Basement Wall Top Restraint
(OP)
Designing a typical basement wall with granular backfill. In design of the wall, I am assuming restraints at the elevated floor level and the basement floor slab. Therefore the wall simple spans.
My question is, if you have wood floor framing, what detail would typically be used to provide the top of wall restraint? In all the buildings I've observed, I havent seen any special connection of the floor joists to the top of the wall. I'm calculating a 900 lb/joist required restraint force, and toenails do not provide anywhere near this amount. I could use a simpson product that provides 750 lb/joist, but thats about it.
Any pointers would be appreciated.
My question is, if you have wood floor framing, what detail would typically be used to provide the top of wall restraint? In all the buildings I've observed, I havent seen any special connection of the floor joists to the top of the wall. I'm calculating a 900 lb/joist required restraint force, and toenails do not provide anywhere near this amount. I could use a simpson product that provides 750 lb/joist, but thats about it.
Any pointers would be appreciated.





RE: Basement Wall Top Restraint
the pressure will be .5 x 33 x 7^2or about 800 #/ft. Because it is a triangular distribution, approx 2/3's will go to the slab and 1/3 to the framing (actually a little less as the framing is above grade) so the load is about 250 per ft. See an AIA Graphics standard for floor connection details (Most libraries have ones that are a few years old - these details rarely change.) The important thing is the plywood floor acts as a diapragm tying the joists togeter. The foundation should not be backfilled untill the floor is complete.
RE: Basement Wall Top Restraint
RE: Basement Wall Top Restraint
DRC1 I'm not sure where you're getting your numbers. Im assuming EFP, with a triangular pressure distribution of 0 to 495psf (per geotech report) over 9'. W/3 = 745 lb/ft into the wood joists and 2W/3 = 1485 lb/ft into the floor slab.
Simpson HGA10KT's get enough capacity, I may just go with those.
RE: Basement Wall Top Restraint
RE: Basement Wall Top Restraint
In NC the minimum wall height usually is about 8'-9.5" which is coursing. The ground is usually 8" (the required minimum) giving approximately 8' unbalanced fill and if you read table1610.1 note c, you will see that soil pressure is 60 psf. That gives you a lot larger force at the top of the wall than you state above. There is a friction value between the sill plate and the wall and the anchor bolts need to cary the remainer. Usually we frame the entire house and not just the floor before the walls are backfilled.