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Wood at concrete treatment 1

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jlholt911969

jlholt911969

Structural
Sep 23, 2020
12
I was just notified that a post-frame building I designed has the posts installed, but the treated section of the post ends about 3" below the top of the 4" concrete slab. This leaves the rest of the untreated column above the soil, but still against the inside of the concrete floor. I am using the floor to pin the column and therefore the column should be in contact with the concrete. I am sure this has happened before but never reported to me, and so it's never come up until now. Since this is a State project the requirements are more stringent, and so they have asked me for a fix. Is there a way for me to treat or protect the column from the concrete? The only thing I can think of is to break out the concrete around the column treat the column externally and repour the floor. As you can imagine the contractor is not happy with that and the State isn't too keen on that repair either. The State will accept what I require, but is there a more non-destructive way of getting this taken care of?
 
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Depends on what you're treating for, but you can look into borate tubes. Drill holes into the post and inject them in. I've only specified them once on a historic house with some damaged wood in places that would have essentially required removing the house to get to, so we settled on those as a means of preserving what was left.

I've never heard of only using a partially treated post, though. Where I am, if the post is treated, the whole thing is treated.
 
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phamENG - it is probably a glulam or nail-lam column:
Screenshot_2023-12-06_120834_rozd2z.png
 
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Weird. Neat, but weird. Nobody does nailed laminated columns around here that I know of (looked into it once for a project), but all our treated glulams are fully treated. Learn something new everyday here!
 
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Yeah these are marketed in our area specifically for pole buildings. The ones I've seen are joined with truss plates to create the splices. They usually have plates on both the sides, for shear transfer, and the ends to transfer the tension loads forming a full moment splice. I haven't seen any finger jointed ones in my locale.
 
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Yes, It's for a pole building MNDOT is using for vehicle storage and maintenance. Since the columns are interior supports they only need to be treated for the bottom 6'-8'. I am not sure how they ended up the way they did because I required the top of footing at 5' below the finished grade which would leave 12" above grade with the top of the slab at 7 1/4" above grade. This should have made the top of the slab about 4" below the top of the treated section and yet the slab ended up 3" above the treated section.
 
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pham... just as a caution, wood subject to brown rot (aka dryrot) can lose 15% to 20% of it's strength and not be noticeably damaged. By the time dryrot is noticed, there may be greater loss. I usually handle this with penetrating epoxy injection. Once the strength is lost, there is no recovering it using an antifungal treatment.

[URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1701898837/tips/Brown_Rot_22-07-20_t5avsa.pdf[/url]

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
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dik - thanks. That was done as well, but I didn't bring it up as the question here was specifically about the treatment.
 
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just for added info, in case anyone was interested... damage is progressive. It never fixes itself.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
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