×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

NC coastal condo building - condemned for steel corrosion

NC coastal condo building - condemned for steel corrosion

RE: NC coastal condo building - condemned for steel corrosion

I noticed this comment:

Quote:

"Inspection of newly discovered corrosion to the structural columns has revealed that the structural integrity of the entire southeast corner of the building has been completely compromised. The cross sectional area of the structural columns in question has been reduced to half of its original size and therefore half its intended capacity. The bolted and weld connections at the floor and balcony systems are entirely corroded away."

That isn't really true. If you lose half your section of a column, the buckling load would be reduced by more than half. With thinner flanges, etc. you could have way less than half capacity with localized buckling.

Check out Eng-Tips Forum's Policies here:
FAQ731-376: Eng-Tips.com Forum Policies

RE: NC coastal condo building - condemned for steel corrosion

JAE:

Depends on the loading condition. If you lose half your area mid column your buckling load can be greatly diminished... at the ends, if pinned, not so much.

Dik

RE: NC coastal condo building - condemned for steel corrosion

If the steel columns / beams are part of a moment frame, the capacity could be diminished by 75% or greater laterally...

Mike McCann, PE, SE (WA)


RE: NC coastal condo building - condemned for steel corrosion

Local flange/web buckling doesn't matter where along the member length.

Check out Eng-Tips Forum's Policies here:
FAQ731-376: Eng-Tips.com Forum Policies

RE: NC coastal condo building - condemned for steel corrosion

JAE:

Agreed... as Mike noted for rigid frame construction; the localized buckling is a bit dependent on the moment at the cross section in play.

Dik

RE: NC coastal condo building - condemned for steel corrosion

The math models might not accurately represent the condition where you can tear big pieces of the web out by hand.

Mike Halloran
Pembroke Pines, FL, USA

RE: NC coastal condo building - condemned for steel corrosion

I haven't seen corrosion that bad since I stopped doing work for the local paper mills.

Professional Engineer (ME, NH, MA) Structural Engineer (IL)
American Concrete Industries
https://www.facebook.com/AmericanConcrete/

RE: NC coastal condo building - condemned for steel corrosion

It would be good if AISC commented on this corrosion, and how it could have happened?

In the 13th edition (and I'm sure other editions)of AISC Steel Construction Manual, the Corrosion Protection section under General states, "In building structures, corrosion protection is not required for steel that will be enclosed by building finish..." When is this statement not true?
Are the structural engineers / architects liable for assuming industry-accepted practice applied to their building, and coatings were not required.

Steel 0
Concrete 1

RE: NC coastal condo building - condemned for steel corrosion

Quote:

corrosion protection is not required for steel that will be enclosed by building finish..." When is this statement not true?

IMHO, when the "building finish" comprises stucco.

Mike Halloran
Pembroke Pines, FL, USA

RE: NC coastal condo building - condemned for steel corrosion

(OP)
I think the building is from the 80s. Unless the then-applicable code required more, it would be hard to make the original folks liable.

Please remember: we're not all guys!

RE: NC coastal condo building - condemned for steel corrosion

Look to the cladding as a failure mechanism that compromised the underlying steel with potential liability for the cladding installer / designer involved here... Not the SE.

Mike McCann, PE, SE (WA)


RE: NC coastal condo building - condemned for steel corrosion

TME:

I've encountered chemical plants where birds could fly through the webs... worse than an OWSJ...

Dik

RE: NC coastal condo building - condemned for steel corrosion

The address, 201 Carolina Beach Ave. South, is (Atlantic Ocean) beachfront property. The corrosion in the photos is typical of long exposure to salt air with occasional submersion in sea water. In the past 30 years, the Carolina Beach part of North Carolina (near Wilmington) has had more it's share of tropical storm / hurricane hits and near misses including associated storm surge to flood parking area under the building with ocean water. MikeHolloran is right, with this type exposure, half the steel may be gone but what remains is really just glorified rust.

After flooding with salt water, architectural covering and coating just accelerate corrosion - year round high humidity together with the salt that remains in the coverings ensure that the steel stays both damp and salty.



www.SlideRuleEra.net idea
www.VacuumTubeEra.net r2d2

RE: NC coastal condo building - condemned for steel corrosion

No hope for this building. I trust there will be examination of other structures there, especially ones built like this. Hopefully, this will give the reinforced concrete industry a leg up. And certainly the hot dipped galvanizing industry. Not much help to the stucco finish folks.

RE: NC coastal condo building - condemned for steel corrosion

I wouldn't park underneath the building...

Dik

RE: NC coastal condo building - condemned for steel corrosion

It could really give a boost to the multistory wood movement that's happening.

Keith Cress
kcress - http://www.flaminsystems.com

RE: NC coastal condo building - condemned for steel corrosion

itsmoked,
How so? Wood has to be connected with steel, and wood also deteriorates with moisture, so if the same cladding system is employed, wood would suffer the same fate.

RE: NC coastal condo building - condemned for steel corrosion

Wood doesn't rust in a salt environment but you make a good point hokie66 about all the ties - though they're all galvanized :) .

Keith Cress
kcress - http://www.flaminsystems.com

RE: NC coastal condo building - condemned for steel corrosion

Just a point of irony to me...
I use to visit that area decades ago and there was a large test facility (acres) for environmental exposure corrosion testing on that beach front strip. I guess the property values got to great and condos replaced it!

RE: NC coastal condo building - condemned for steel corrosion

They're doing 14 storeys in wood... and with the cladding they are using on Grenfell Towers, it could be interesting.

Dik

RE: NC coastal condo building - condemned for steel corrosion

Nah, plenty of all-wood ties in use... have been for centuries. I imagine with some creative design, joints could be made that are just as strong as wood-to-metal ties. They may be bulkier overall, but just as strong.

Dan - Owner
http://www.Hi-TecDesigns.com

RE: NC coastal condo building - condemned for steel corrosion

As far as parking my car under there, I would for sure. But I'm looking to get rid of it.
I would of never thought that steel encased like that, even in stucco, would corrode that badly. I can't help wonder if there's another issue causing the problem. Is the stucco of extremely poor quality?

RE: NC coastal condo building - condemned for steel corrosion

Isn't the problem with stucco is that it doesn't breath? If water gets in, it will rot out and rust up whatever is there? You don't know you have a problem unless you test it or actually see visible problems but by then it is too late?

I have been looking at houses here in Houston, which is very humid and stucco I am told is not good in moist environments. People have stucco houses here because they like the look but you have to watch them. There is a townhouse complex down on montross that you can literally peal off the stucco wit your hands. There is another place we thought about bidding on and then passed when our realtor got a hold of a stucco report for the house and it looked like it needed 100k of work. Maybe, I am wrong but why would you put a stucco building on the shore?

RE: NC coastal condo building - condemned for steel corrosion

(OP)
There have been fortunes made in coastal NC off repairing screwed-up stucco.

Please remember: we're not all guys!

RE: NC coastal condo building - condemned for steel corrosion

Quote (TerryScan)

And subsequent development on story:
http://www.starnewsonline.com/news/20170713/caroli...
Looks like a friction fire to me.

The insurance policy got to rubbing up against that engineer's report.

RE: NC coastal condo building - condemned for steel corrosion

I understood traditional stucco breathes okay, it is the modern look-alikes that don't.

RE: NC coastal condo building - condemned for steel corrosion

That place has been in a couple of hurrycanes. I'd bet the wind has driven salt water right thru a bunch of crappy stucco that has modern crappy paint as its only protection.

The poor building has been in a collision where; unprotected steel, bad stucco, saltwater, hurricane winds, and modern paint all came together.

Keith Cress
kcress - http://www.flaminsystems.com

RE: NC coastal condo building - condemned for steel corrosion

The LaQue corrosion test lab had two components, outdoor lots for exposure testing (25m and 250m lots) and a lab with both indoor and outdoor seawater exposure racks. The lab is no more. But the 250m lot is still there, with some coupons from the 1950's when Francis LaQue built the site for INCO.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, Plymouth Tube

RE: NC coastal condo building - condemned for steel corrosion

As an aside: HurryCane. Sounds like a project management tool for beating subordinate staff and suppliers with.

EDMS Australia

RE: NC coastal condo building - condemned for steel corrosion

Quote (smoked)

HurryCane

Someone noticed!


Interesting history EdStainless.

Keith Cress
kcress - http://www.flaminsystems.com

RE: NC coastal condo building - condemned for steel corrosion

Thanks EdStainless, the site was much bigger than 1.5 acres in my memory :)

RE: NC coastal condo building - condemned for steel corrosion

Interesting Ed. I know I've seen references in various alloy data sheets and articles to the site.

RE: NC coastal condo building - condemned for steel corrosion

There was a very large corrosion test site in SoFla, before Hurricane Andrew.

Mike Halloran
Pembroke Pines, FL, USA

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members! Already a Member? Login



News


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close