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Long A325 Bolt Alternatives

waytsh

Structural
Joined
Jun 10, 2004
Messages
384
Location
US
Hi All,

I have designed a reinforcing solution for a barn timber using bolted steel side plates. The contractor is having trouble sourcing the long A325 bolts required. I can't really use lags bolts, at least on the backside of the timber because of clearance with the roof. Is there a good alterative that might be a little more readily available? Could I use cut down threaded rod or maybe F1554 Grade 55 anchor bolts? I figure you clever folk will have some ideas.

Thanks!
 
F1554 Gr105 rods have strength that's roughly equivalent to A325 bolts. We commonly spec it when the required bolts are not available.
 
Do you really need A325? Can they use A307 threaded rod? Otherwise, they can use F1554 Gr 55.
 
Do you really need A325? Can they use A307 threaded rod? Otherwise, they can use F1554 Gr 55.
I might be able to squeak by with A307s in some areas. If I can't I can look at increasing the number of bolts.
 
Hard to imagine the bolt grade would be the limiting factor.
 
F1554 Gr105 rods have strength that's roughly equivalent to A325 bolts.
Good call... I generally spec Grade 55 S1 for anchor rods... not as strong but better than A307.
 
Hard to imagine the bolt grade would be the limiting factor.
This. There's a reason A325 is rarely spec'd in wood construction. In nearly every connection I've ever considered in wood, the wood failed a check long before the bolt did. If you're finding that you need a bolt stronger than A307, look real close at your calcs around the wood failure mode.
 
I'm curious to see the detail as well. Seems like even for a through bolt with side plates plowing through the wood would always govern.
 
High spec threaded rod is great and all, but given the same thought as above, you might want to think about coil rod. Ubiquitous and versatile.
 
Hard to imagine the bolt grade would be the limiting factor.
Fair point, I will double check my numbers. They are in white oak with a very large edge distance.
 
What about SAE Grade 5 bolts?
I believe strength is similar and they can be purchased from McMaster
 

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