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Foundation Wall Repair Suggestions

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XR250

Structural
Jan 30, 2013
5,291
This is a project of mine where:
a) the contractor did not install any rebar in the wall
b) it was my understanding that the site was flat so there would be no meaningful retaining
c) not enough anchor bolts were installed
d) The top courses of the CMU were not grouted where they transitioned from 12 to 8 and from 8 to 6.

Below is my repair concept. Cut the face shells of the CMU sufficiently to be able to install the rebar and grout. That will take care of my retaining and give me something to resist the uplift with (approx 200 PLF). Somehow I need to tie the top 6" CMU to the rest of the mess to resolve the direct tension. Was thinking since they already have the face shells cut out, they could drill upwards into the 6" block and epoxy rebar into the underside. Alternatively they could drill down through the sill plate and the 6 inch block and try to epoxy rebar into the 8" CMU below. Add additional post-installed anchors as needed. None of this repair is ideal though.

Thoughts?

cmu_vt9jho.png
 
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Do they have bond beam reinforcing in the 6" block? Maybe they could extend anchors into the 8" block with post installed option and install a new horizontal bond beam there when adding the verticals. If there is bond beam reinforcing, maybe you could use two bars, one epoxied up into the 6" block and one epoxied into the foundation and lap the bars for ease of installation. If not, I believe extending extra long post installed threaded rods epoxied into the 8" may be the best course.

I'm assuming the wood wall and floor are already installed? It appears (assuming this is to scale with no break lines) the wall is 5 courses high where grout is needed? I hate the idea of removing and replacing more face shells that needed, they just never seem to last once re-installed, but I don't see a great option around it really.

Only other options I see are 1. external reinforcement like FRP, 2. Replace wall completely and built right or 3. install a new wall interior and tie the two together properly. None of these seem feasible however.
 
"Do they have bond beam reinforcing in the 6" block?"
Not likely.
"I'm assuming the wood wall and floor are already installed?"
Yes walls and slab are constructed.
"5 courses high where grout is needed?"
6 courses actually
"I hate the idea of removing and replacing more face shells that needed, they just never seem to last once re-installed, but I don't see a great option around it really."
I was not going to replace the face shells. Just have them form up the outside with plywood or whatever.Tthe veneer will cover it.
External FRP will not work as the gravel side is where the reinforcement is needed
"Only other options I see are 1. external reinforcement like FRP, 2. Replace wall completely and built right or 3. install a new wall interior and tie the two together properly. None of these seem feasible however"
None of those are feasible.
 
Sounds like your idea with the addition of bond beam reinforcing and extending new anchors to 8" bond beam may be the only real option here.
 
I don't see an option better than what you've presented. My preference would be to access from the top side and epoxy a long holdown type anchor into the grouted 8" cells. The tricky part would be aligning with the grouted cells but I imagine they can figure it out.
 
I wonder if your option 2 (just rebuild the damn wall correctly) isn't less expensive than all the labor and surgical work required in your other options.

Labor is expensive for picky little "fixes" like post-installing rebar in CMU.

 
The building is completely framed. If the wall is removed, all the retained gravel spills out. Not really an option.
 
I know it is common practice to grout the course below a thickness change in the masonry. Is this in the IRC anywhere?
This was discussed here where the long lost KootK questioned its necessity. I imagine the builder will be wanting not to do that.
 
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