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Loose Anchor Bolts

Loose Anchor Bolts

Loose Anchor Bolts

(OP)
I have some loose anchor bolts on an old concrete corbel (bracket). The bracket supports a roof truss.
The anchors appear to be regular bolts that were cast in place with the bolt head obviously in the concrete.
The bolts appear to have worked loose as there is some gap between the nut and plies of the truss.
I have been trying to think of a fix for the condition, but there is really no way to remove the old bolts.
Ideas?

RE: Loose Anchor Bolts

Can you add a post installed anchor pattern around the existing anchors.  Perhaps at 10 1/2" c/c. If vibration or cyclical loading caused the other anchor problems, I would suggest an epoxy anchor.   If the existing anchors are loose, the anchors will not share the loading, or impact on the concrete.    

http://www.FerrellEngineering.com

RE: Loose Anchor Bolts

(OP)
There is no room on the corbel for another anchor pattern and not really room to install post-installed anchors (no room to drill holes).

I can't beleive the anchors even came loose unless the original installation was piss-poor.  

RE: Loose Anchor Bolts

Can you fill in around the bolts with epoxy, to make them not loose anymore?  Like pressure inject around them?  Of course, that's probably really difficult in practice...

RE: Loose Anchor Bolts

(OP)
slta-
you maybe onto something there

RE: Loose Anchor Bolts

you'd have to clean the holes really well.  epoxy stuck to dust is just dusty epoxy.

RE: Loose Anchor Bolts

I remember a guy was going to try to"drill" out a similar bolt. He was to get a drill that would lock onto the end of the bolt, spin it while pulling outward. There was betting on whether it would happen or whether the head would catch and snap.

Unfortunately, I moved on so I can't say if it worked.

I agree that epoxy on dust wont "glue" it in position, but it could lock it in place mechanically.

Michael.
Timing has a lot to do with the outcome of a rain dance.

RE: Loose Anchor Bolts

(OP)
I suppose there has to be a way I could recommend cleaning the hole. High pressure air potentially? Through a small wand of some sort?  

RE: Loose Anchor Bolts

How big a wiggle space are you talking?  Meaning is there room to get one of those keyboard cleaner nozzles down in there?

RE: Loose Anchor Bolts

(OP)
I've yet to go back and take a second look.  

RE: Loose Anchor Bolts

How many plies are in the truss? If you can't get in there to inject epoxy could you possibly design an attachment to anchor the truss to the wall?

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