Steel Tube Cracking

[walrus102882]

I'm just curious how others repair a cracked hollow section? I have a hollow section that was not capped and water was able to enter and freeze. This resulted in a vertical crack just above the base plate. Due to the expansion of the steel the concrete was also damaged. In a case like this, I'm just curios if others prefer to replace the entire section or cut away the damaged area and weld a new section in its place? I included a pic to give you a better idea.

Thanks

 

[XR250]

if the column still has a sufficient un-corroded section, you can likely just weld the crack up. Sealing the top of the column also seems like a good idea.
Might want to put some expansion joint around the column prior to the concrete repair as water getting between the two can also cause corrosion expansion.

 

[oldestguy]

I'd cut the tube off above the floor level and add a new plate there, but have drain holes. Replace the concrete up to the plate (maybe first) and bond it to the old with a Portland cement past applied to dry undisturbed surface. Why bury the undrained cavity down in the concrete to begin with?

 

[walrus102882]

Thanks for the replies. I'm dealing with someone that is insistent on replacing the entire 20' foot section. I personal find this unnecessary and much more work.

Thanks Guys

 

[SteelPE]

I have had this happen before under similar circumstances (difference being column base was flush with slab and the crack was on the face of the tube). In this instance we had them drill a hole at each end of the crack (to stop the crack) and re-weld and then drill a weep hole just above the base plate.

 

[oldestguy]

Unless this was your original job, I'd tell the owners to get someone else. Goofing around like this is costly in terms of time for you. A reputation for costly work also is not good.

 

[Once20036]

I don't think this needs to be too complicated.
Depending on the condition of the steel inside the tube (can you get in there with a boroscope?) you can drill the ends of the crack and re-weld as suggested above, or drill the ends of the crack and weld a new angle along the corner.
Given that this looks like it supports a small canopy at an exterior door, I can't imagine that replacing the whole thing would be necessary.

Definitely add a means to get the water out - maybe fill the tube with concrete to match the adjacent concrete elevation and add a drain hole.
For the concrete - I'd epoxy some dowels into the existing concrete on each side of the tube - it's surprising to me that there's no reinforcing visible in the pic.

I agree that having a reputation for costly work isn't good, but a reputation for refusing work may not be any better.

 

[thaidavid40]

Weld side plates taller than the crack on all four sides to supplement the weakened section (this keeps it symmetrical), and weld them at the top to the tube faces. Like many others have suggested: drill crack-terminus holes at each end of the crack, and drill a weep hole at the top of the base plate (just above the fillet weld).

Thaidavid