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How to anchor new CMU block wall to existing perpendicular brick walls? 1

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Oct 1, 2020
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I am currently in the process of designing an exterior, load bearing CMU wall for a church. The church is around 100 years old and was originally constructed with clay brick walls (roughly 4 4" bricks thick) with an additional layer of brick veneer. The wall I am designing is 44 feet wide and about 40.5 feet tall, to be constructed on top of the existing limestone foundation and attached to the two existing exterior walls. The existing wall will be demolished and the veneer bricks will be reused in order to match the other walls.

My question is:
What type of anchor would be appropriate to sufficiently tie the new CMU wall to the existing brick walls?

Thanks in advance,
CSC

 
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So these are corner connections between your CMU wall and two, perpendicular brick walls?
 
Is the existing wall solid or has void in between layers?
 
No worries. When it's your baby and you can see it perfectly in your own mind's eye, it's all but impossible to fully anticipate what a newcomer might need. Classic cognitive bias.

Maybe something like this if I've got the corner condition rigth?

C01_g1tmni.jpg
 
r13,

The existing walls are solid.

The main problem with the existing walls are the mortar joints in the exterior layer. If possible, I would like to avoid anchoring the CMU blocks to mortar joints.

Thank you
 
Kootk,

That is exactly the situation. Do you think it would be a good idea to drill and epoxy or drill and grout the dowel bars into the existing wall?
 
OP said:
Do you think it would be a good idea to drill and epoxy or drill and grout the dowel bars into the existing wall?

Yeeeees... I take it you feel otherwise?

1) I feel that some connection is prudent so that you don't get separation at the joint or differential settlement at the intersection.

2) The concern is always to try and do something that will be robust and not damage the existing wall.

3) I'd considered clip angles on the inside corner. I feel that would just fall apart though, unless the brick is very solid. You'd have limited edge distances on the bolts.
 
Kootk,

I agree with you. Originally, I was leaning towards grouting the anchors/dowel bars into the existing walls. I'm just not sure that grout would provide sufficient adhesion and I have very little experience with epoxies.

Thanks for all of your help.
 
I don't know the "4 4"" indicates a 4'-4", or 44" wall. But it is a thick solid wall indeed. I'll place the CMU wall in between the existing wall (infill), which makes connection easier. In addition to drill and grout, you can provide interlock between the new and existing walls, by removing pockets of the existing wall.
 
This system might appeal as it's intended for masonry that might have some voids in it. Link. I don't think that you need a ton of capacity out of this connection. Just kind of a nominal reconstituting of the monolith so to speak. I've never tried to core and grout something like this so I'm, sadly, unable to comment on that with experience.
 
You're most welcome. Do return to tell us about your final solution.
 
Update:

My final solution was to drill and epoxy #3 bars at 24" OC (every 3 CMU courses) with 18" of embedment into the existing walls.

However, there was an ice storm in late December that revealed more structural problems with the building only to be exacerbated by the winter storm from February.

The owner decided to demolish and do a complete rebuild due to these other issues.

My apologies for taking so long to post an update and thanks again for all of your suggestions.

-CSC
 
No worries, thanks for reporting back to close up the thread.
 
That's a shame - hate to see a historic building go. But churches are having trouble raising funds for the sort of upkeep/repairs that are needed, and insurance rarely covers it. So it makes sense to clear the slate and start with a less expensive and more efficient building.
 
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