Basement wall with wood flooring
Basement wall with wood flooring
(OP)
I've got a retaining wall in a basement on a house and I'm trying to use the floor to restrain the top of the wall so I don't have to design it as cantilevered. I'm having a problem coming up with a detail that I feel good about. I need like 1100 lb/ft (strength level) restraint at the top of the wall, so the typical joist bearing on treated ledger on the top of the wall with J/L bolts into the wall isn't going to cut it. I'm left with framing 16" deep I joists into the side of the wall. Has anyone done this before? I'm worried about the ledger connection since the joists are 16" deep. Any suggestions? Thanks.






RE: Basement wall with wood flooring
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Basement wall with wood flooring
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Basement wall with wood flooring
RE: Basement wall with wood flooring
I can't open the attachment Kootk posted for some reason - but I suspect it is the AHITC Lateral Bracing guidelines. See Fig. 4c.
I use a 48" stainless steel strap w/ corrosion resistant concrete screws to the wall.
RE: Basement wall with wood flooring
Jeez... I need to be less predictable.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: Basement wall with wood flooring
Mike McCann, PE, SE (WA)
RE: Basement wall with wood flooring
the name of the attachment is also, 'Guidlines_for_Bracing_of_Residential_Foundation_Walls.pdf'
RE: Basement wall with wood flooring
If it's that big, you may need to resolve the lateral forces on the other end of the floor. Joists at 16" o.c. would have a compression force of 1500#!
Maybe a cantilevered wall (or counterfort wall) is required.
When I am working on a problem, I never think about beauty but when I have finished, if the solution is not beautiful, I know it is wrong.
-R. Buckminster Fuller
RE: Basement wall with wood flooring
RE: Basement wall with wood flooring
RE: Basement wall with wood flooring
(50×8×8/2)/3 = 533#/ft. Seems high.
Mike McCann, PE, SE (WA)
RE: Basement wall with wood flooring
-115PSF * .33 (assumed Ka) * 1/2 * 8ft^2 (wall height = 1214psf @ 1/3rd wall height from top of ftg
-equv tabular load brings us: (8ft*1214plf*5.5ft*x2.5ft)/(8ft^2) = 2090#
-2090#/2 = 1045# taken by top and bottom w/o factoring loads.
I can see how he is getting near 1100#/ft
RE: Basement wall with wood flooring
The last house I looked at with 14 ft. of backfill had slid about 3" off the opposing foundation wall.
RE: Basement wall with wood flooring
Mike McCann, PE, SE (WA)
RE: Basement wall with wood flooring
P(acting at 1/3rd height of wall, in #/linear ft) = 1/2*(Active or passive coefficient)*(Unit weight of soil)*(BF. height)^2