Field bending threaded rod

[bluedog225]

I’ve been known to field bend a piece of rebar or steel a bit. I read somewhere that the reduction in strength was pretty minimal. I don’t really know if that’s true or not.

But what about 5/8” threaded rod? Ok to put in a foot or two bend in a 10’ stick? Or should I just cut it and use coupling nuts to get it in place?

It seems to bend too easily. Is threaded rod different?


The application is a tie down for a top plate.

Thanks

 

[LXCam]

You’re not going to bend a piece of 5/8” allthread by hand/foot without it being a huge radius. The biggest issue is if you use any type of mechanical means the rod will break. The metal is not maluable enough to bend without breaking because of all the stress risers.

Beyond that, why do you want to do this. Are these inbeds and if so just buy the right kind of j bolts and call it a day.

 

[bluedog225]

Well, I’ve got these 10 foot sticks of zinc 5/8 inch threaded rod. I got them from a reputable supplier. Nothing special. Just mild steel threaded rod. And I’ve got some 5/8 for forged headed bolts from Portland bolt sticking through my bottom plate. I want to tie those bolts to the top plate in a couple of places before I close up the walls. Peace of mind.

It‘s roughly 20 feet from the foundation to the top plate. And I’ve got to go through framing and blocking on the way. I can cut out the blocking, but the second floor is framed in.

As I’m threatening this rod down through my holes, I put a pretty good bend in it without much difficulty. While I admit I’m a magnificent specimen, I’m on the wrong side of 60 to be claiming that I put a lot of force into this.

And that’s why I’m asking. This stuff bent a lot easier than 5/8 rebar would’ve bent. I was surprised.

I’m wondering if threaded rod was qualitatively different? No point in putting it in if I’m going to weaken it significantly.

Thanks

 

[whateg01]

Bending a bit over a 10 foot length is different that putting a 6" CLR bend in it. Are you just talking about a gradual bend?

 

[bluedog225]

Yes. About 2 foot out of straight on a 10 foot stick. A large radius.

 

[PCustoms]

Why do you keep insisting on re-designing commonly available, rated, structural ties?

Simpson makes a bracket for just about any (real) scenario you are going to encounter.

 

[bluedog225]

Do you have any insight on the threaded rod question?

 

[PCustoms]

Do you have any insight on the threaded rod question?

Yes, it will bend.

Yes, I likely weakens the rod.

No, it's probably not correct for this application. Are you bolting between plates, or is the bottom bolt embedded in concrete?

If embedded, is it a proper anchor bolt?

If plate to plate, have you provided adequate bearing surface?

 

[LXCam]

Got ya. Instead of bending it into the framing why don’t you just get some rod couplers and tie it into the anchor bolts?

 

[bluedog225]

Got ya. Instead of bending it into the framing why don’t you just get some rod couplers and tie it into the anchor bolts?

Yes. Coupling nuts may be the way to go. I wanted to check to see if anyone had particular insight into threaded rods.

 

[bluedog225]

Yes, it will bend.

Yes, I likely weakens the rod.

No, it's probably not correct for this application. Are you bolting between plates, or is the bottom bolt embedded in concrete?

If embedded, is it a proper anchor bolt?

If plate to plate, have you provided adequate bearing surface?

I’m both bolting between plates and from headed anchor bolts that are embedded in the concrete per the engineer’s specifications. They are proper anchor bolts per the engineer.

I am fan of Simpson’s solution as well. And am using HDUE’s as per Simpson’s information below. On the studs or on the rafter depending on the site.

 

[larry_g]

If you pick up the rod from one end and hold it horizontally how much does it deflect just from it's own weight? Could be a clue to just how flexible the thing is. I really doubt that you are bending it beyond its elastic strength...

lg
no neat sig line

 

[Youngandfree]

Well, I’ve got these 10 foot sticks of zinc 5/8 inch threaded rod. I got them from a reputable supplier. Nothing special. Just mild steel threaded rod. And I’ve got some 5/8 for forged headed bolts from Portland bolt sticking through my bottom plate. I want to tie those bolts to the top plate in a couple of places before I close up the walls. Peace of mind.

It‘s roughly 20 feet from the foundation to the top plate. And I’ve got to go through framing and blocking on the way. I can cut out the blocking, but the second floor is framed in.

As I’m threatening this rod down through my holes, I put a pretty good bend in it without much difficulty. While I admit I’m a magnificent specimen, I’m on the wrong side of 60 to be claiming that I put a lot of force into this.

And that’s why I’m asking. This stuff bent a lot easier than 5/8 rebar would’ve bent. I was surprised.

I’m wondering if threaded rod was qualitatively different? No point in putting it in if I’m going to weaken it significantly.

Thanks

They don't use threaded rod for structural support where rebar is used for a reason. 5/8 threaded rod has a much smaller core if you take the threads off.

 

[PCustoms]

I'm still confused what your bending

 

[PopcornSutton]

Allthread isn't designed for lateral load, just pull strength. Since you are fishing this up through framing, I think couplings would be the proper way. For a tie down, it would function just fine. But if you put a slight bend in one just to align through the holes, I doubt you would harm the intended strength.

 

[bluedog225]

If you pick up the rod from one end and hold it horizontally how much does it deflect just from it's own weight? Could be a clue to just how flexible the thing is. I really doubt that you are bending it beyond its elastic strength...

lg
no neat sig line

I held a piece of the ten foot 5/8” threaded rod up. It doesn’t bend much at all under its own weight. Maybe an inch.

The piece of 5/8 I bent to install in the wall is already installed and tightened down.

But by way of example, here’s a piece of 7/8” threaded rod about 3 1/2 feet long. My impression is it bends much more easily than I would expect. Maybe just the smaller core diameter.

I’m going to cut and coupling nut the rest of it.

Thanks all.