Reinforce Nonreinforced masonry wall with Insulation.

[EngStuff]

I have a situation i am not too sure on what to do. I have an existing non-reinforced Masonry wall that is insulated. The new roof is causing a bit of uplift on the wall(changed style and orientation) Thus i have to reinforce it. Originally, we specified to grout and reinforce the wall. Now we got word that it's insulated at every core, so the mason cannot make that work.

two options i thought about:

1. I was thinking to reinforce both sides with carbon fiber straps but thought about the weather exposer that might cause issues, also the client having issues with seeing straps on the outside every so often.
2. Reinforce both sides with steel channels, but the client is against having steel channels on the outside due to the "ugly" look.

Another option that i shot down was just reinforcing on the inside with steel channels, connecting every 16" from bottom to top. Spacing the channels every so often. I was against it, because it might help when wind blows against the wall, but not during "suction".

Another possible option i was thinking was to grout the top 2 or 3 cores down throughout the wall length to cancel out the uplift. It will make the wall top heavy, but if it works, why not?

Also, there are some vertical and diagonal cracks on the wall. This is kind of the main reason why i want to reinforce the wall.

what do you guys think?

Thanks!

 

[dik]

What is the insulation? Is it vermiculite, or something else? What is the foundation? a strip footing? a gradebeam? Can you make a small opening at the bottom to drill and insert an epoxied threaded anchor that goes to the top and devise an attachment plate at the top? These could be every 8' or 10' or whatever? with a bond beam at the top. I've often knocked out the webs of masonry walls to create a bond beam that was 3 or 4 courses deep.

Rather than think climate change and the corona virus as science, think of it as the wrath of God. Feel any better?

-Dik

 

[le99]

Depending on the existing roof-wall connection, you may be able to dill and epoxy grout bars at a regular spacing to attach a bearing plate on top, then set and connect the roof support members to it. This should solve the uplift problem, assuming the roof was originally fastened to the wall through short anchors embedded in the grout.

 

[EngStuff]

Insulation is spray foam from what i was told. Foundation is a strip footing. I do like the plate idea, but for this particular job, I think it still comes down to the wall being spray foamed and wouldn't be possible to push it through.

Also a quick note, acetone will be too expensive to do for this project.

 

[EngStuff]

This should solve the uplift problem

Issue comes down to it being non reinforced, code does not allow us to move forward with these types of walls when we have uplift on them.

 

[le99]

How did they get a permit in the first place? Was there a major change after the permit was issued?

 

[EngStuff]

How did they get a permit in the first place? Was there a major change after the permit was issued?

It was a situation where a fire occurred in an existing building and burnt the whole roof down. They ended up redesigning the roof and rotated it due to Architectual reasons. Thus the existing exterior non-load bearing walls turned load bearing.

 

[le99]

Well, sounds like a big mass. If the bending stress of the wall is kept within allowable, you might consider adding reinforced pilasters for roof hold-down purposes only.

 

[masonrygeek]

I don't like to recommend proprietary products in this forum, but you might want to consider something like Ruregold, which is like FRP overlay, but is cement based:

https://www.conspec-rep.com/products/ruregold/.

Something like that could work and be exposed.

 

[Brad805]

Simpson Strong Tie recently sent us an introduction to their URM reinforcement site: Simpson URM

 

[EngStuff]

Thanks guys,

I think those should work out great!