This is a shareholder issue, not so much engineering. Keep it making money until you can get your own money out.

Riddled with rust does imply structural deficiency. That would be an engineering disaster.

But, now that the post is here and maybe our coatings engineers will be floating around, does anybody have experience with gelled calcium sulfonate based coatings? They seem like they would be ideal for this case as they require minimal prep work and most of the steel is not accessible to tourist's fingers. I'm interested in bringing said coatings into the marine industry.

Thanks, Tug... just like they should have had sprinklers at Notre Dame...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

I wonder which will fall over first: Eiffel or Millennium Tower.

It's important to remember that the latter was build with 21st Century technology (well, 20th, anyway), as opposed to that old one. Which, by the way, is NOT made of concrete. Sad!

The Eiffel Tower is over a hundred years old! It should be torn down and replaced with affordable housing. With retail on the lower floors. But NO parking!



spsalso

sps... do you want to start a pool? I fell out on the other engineering site because I suggested a pool for when the US hit their first 100,000 (I think) Covid death...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

If you're going to go there, can we include bio engineering on this forum? What a disaster the vaccines ended up being. Only protective against an extinct virus, caused the same symptoms of real infection, and yet here we are still advocating for paying for them. No distinction between deaths with COVID and due to COVID.

Bitter subject. I work in the only county in the USA that has a mask mandate... Quad vaccinated mask wearing Fauci is on his COVID rebound after taking his first round of Paxlovid... I can't even catch the dang virus. It finally made it's round through my company and I got conjunctivitis instead.

The press may be exaggerating a bit about the Eiffel Tower. Fancy that! One thing the tower has in its favor is that it is iron, not steel. Iron is much more resistant to corrosion than carbon steel. But it will still corrode, and needs to be coated. Eiffel recommended coating at a seven year interval. Modern coating should provide improved protection, but the system should be carefully selected by coatings specialists.

The vaccines are considered to be an outstanding success. Saved millions of lives.

No major side effects, extremely low adverse effect. 100 times less than the contraceptive pill.

2nd gen in testing for the vector vaccines which is going for a different bit of the virus that the spikes. mRNA vaccines have been re engineered and tested on rats and should be released soon. They are on the test regime the same as the flu vaccine.

And cases of Omicron A5 are rocketing. The old vaccines have zero ability to stop catching it. But significantly reduce fatality rate. But as most have had the virus or already vaccinated the pro's don't think it's worth while doing another round of boosters with mass population. Just targeted groups

To be honest I think alot of Parisians would be happy it getting scrapped.

Alistair_Heaton,

The Eiffel Tower is France's answer to the Brooklyn Bridge. Someone is always claiming that they are going to scrap it, and that they are authorized to sell it to you.

--
JHG

Quote ( )

"The Eiffel Tower is riddled with rust and in drastic need of repairs but will only receive a cosmetic paint job ahead of the 2024 Olympic Games in Paris, according to leaked reports. "

Quote ( )

"'In an emergency, in some places, a simple coat of paint is just brushed on the existing layers, which are flaking and do not hold,' another anonymous expert warned. "

this is second hand information from unnamed and anonymous sources and from unnamed "reports" published in a rag. I would take this with a few grains of salt

Hokie... is it wrought iron? This has excellent corrosion resistance. Lindsay's century old wrought water tower is in fair condition. The new steel one, not so good...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

cvg... I suspect there are some problems and it has been 're-coated' several times. The coating systems appear to be improper and not working.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Puddle Iron apparently.

https://www.google.co.uk/amp/s/amp.theguardian.com...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

dik
according to the article, it has been painted at least 20 times which indicates a fairly good maintenance schedule (at least for the painting). and I would expect it does have some problems, but would really like to see an engineering inspection report, not an editorial piece in the daily mail...

to me... painting it 20 times is not a good maintenance schedule. It only represents a poor choice of coating material.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Thanks LI... I'd not heard the term puddle iron (sheltered existance, I assume) "Puddle iron was the first inexpensive wrought iron to be produced on an industrial scale. The puddling process was invented by Henry Cort in 1784 and is considered a key technology of the industrial revolution of the 19th century. At the end of the 19th century, the process was slowly replaced by the Bessemer and Siemens-Martin processes."

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Looks like it's all done by hand and with brushes.

https://www.painttalk.com/threads/repainting-the-e...

That means SSPC-3 for prep and no control of mils during paint application. That would explain the frequent repaint interval.

One thing that you have to keep in mind is that when the city of Paris agreed to host the 1889 Worlds Fair, the understanding was that the structures built for the fair, including the Eiffel Tower, would eventually be dismantled and removed after the fair closed. However, due to the cost of erecting the tower, Eiffel and his investors cut a deal with the city that for the next 20 years they would receive all the profit from any revenues generated by tourism and the concessions located in the tower. After that the city would take full possession and do with it as they wish. But that still meant that when it was being designed and erected, that the plan was that it was only temporary. This may have led to certain shortcuts having been taken with respect to any long term plans for maintenance and repair.

Of course, after 20 years, the tower had became an even more famous symbol of Paris (although not all Parisians would agreed with that) and so the plans for dismantling it were abandoned altogether.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

If they need to subsidize a touch-up, I’d love to see a recreation of Bill Overstreet’s flight underneath.

I understand that that was to happen with the Fuller dome at the Montreal expo in '67, and that they ran into deflection issues during the erection... and they had to weld the connections... rather than dismantle it, it was left.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

The puddled iron process can produce wrought iron. Puddling can also produce steel. The process is no longer in commercial use.

Wrought iron - what is reportedly used in the Eiffel tower is very low carbon content (less than 0.08%), semi-fused mass of iron with fibrous slag inclusions (up to 2% by weight). In other words it is a composite material. It has better inherent corrosion resistance that uncoated steel.

Wrought iron is not generally considered a weldable steel (by arc welding process), but is very easy to drill, so it is ideal for riveted construction.

Wrought iron is no longer produced on a commercial scale,

My guess is that the lack of good surface prep has compromised the applied coating systems.

Quote (My guess is that the lack of good surface prep has compromised the applied coating systems.)

I would concur with that... big time.

I understand that there's a fairly high demand for 'real' wrought iron. Not sure, but have heard that...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

My understanding is that wrought iron is still in demand for artistic uses or in restorations. Now while wrought iron might be more resistant to long-term corrosion, it does rust and almost immediately, if the conditions are right, just that once you get that layer of rust, it pretty much stops.

Six years ago I did a full restoration of a Singer 66-4 sewing machine which was manufactured in 1927 (for a more comprehensive review of the restoration effort, please visit Singer Sewing Machine Restoration).

That being said, the lower framework of the sewing machine base was made of wrought iron, as seen in this photo (taken before I started the restoration):


May 2016 (Sony a6000)

And here were all of the pieces before I took them to the sandblasting shop to get all the old paint removed:


May 2016 (Sony a6000)

When I went to pick-up the sandblasted parts, I was told that I should get at least one coat of paint on them within 24 hours, otherwise they would start to rust. I put my first coat of primer on them before I went to bed that night as I was taking no chances.

BTW, this is what the fully restored sewing machine looked like when I was finished (as I said, if you want a more detailed review of the entire restoration project, click on the link I posted above):


July 2016 (Sony a6000)

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

Yes, it behaves a bit like the type of modern steel which forms a skin of oxide which in turn protects the core. Weathering steel, Corten and the like.

Also aluminum, in which the oxide on the outside protects the inside. Different chemical processes, I think, but similar result.

I doubt the Eiffel tower will ever have all the old coatings removed. Best to just continue to remove the loose stuff, and recoat with surface tolerant coatings.

John...is that wrought or cast?

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Quote (Best to just continue to remove the loose stuff)

I think it's best to remove the old stuff and use a proper coating system.

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

They might have been sand cast, but whatever the case, they were Iron and NOT steel. After the sandblasting, the material was very dark, almost black. This is one of the pieces, after sandblasting, but before I primed it:


May 2016 (Sony a6000)

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

dik,

As to removing all the old stuff, I doubt that is at all practical. Yes, it would certainly last longer that way, but how would you do it?

I have no idea of the constituent of the existing coatings... determine what they are and then decide how best to remove them... solvent and/or blasting with dryice/walnuts, or whatever. For safety and environmental issues, it may be necessary to 'encapsulate' the tower for a few months. I'm pretty sure something can be worked out. There could be 1/4" of lead based paint on it... dunno, but have to find out first, and there could be many types of paint... first it is necessary to find out what is there. The old line comes to mind, "People that say something is impossible, shouldn't interrupt those that are doing it."

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Oh, gosh!

Another opportunity for a "post modern" viewpoint:

A competition to replace the tower. It is over 100 years old, a clear signal based on news reports that it has exceeded its life.

The rules:

It must be concrete, with perhaps some highly stressed steel stuff inside. That will never rust.

It must be asymmetrical, because symmetry is colonial. Or maybe imperial.

It MUST have affordable housing and no place to park the cars of the people who live in the affordable housing. What the HELL are we letting THOSE people have cars for, anyway?

The submissions must post-date the collapse of the Millennium Towers, because...of the symbolism...which is post capitalistic..I think.


I'll have another martini!

Thanks,


spsalso

Thanks for the contribution!

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Well, I must admit my flippant dial was turned up to 11.

But if we were to assume the Tower had to be replaced, what would it be?

Exposed-structure steel/iron is hugely out of fashion. It's likely because concrete is cheaper to use, rather than artistic whim. Which would reinforce the use of concrete for the replacement: "Not only is it built "the current way", but it's cheaper."

Asymmetry in building shape has become a way for buildings to be "different" and more notable than the old symmetric skyscrapers.

And affordable housing? It's what you do to get government approval for your project, and to perhaps deflect protesters and activists.


This all assumes that the old one wouldn't be replicated, of course.



spsalso

Plan to visit ET in September, so hopefully, it will last at least until then

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
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You forgot the happy face...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

Once a large portion of buildings are asymmetric, that won't be novel. What will architects dream up next for us engineers to design? Floating Buildings?

Exposed rivited construction is no harder to repaint than anything else until it gets corrosion inside of rivited joints which then must be disassembled to repair. That gets really expensive. I once worked on a gantry crane with that problem, we eventually cut it up for scrap.

Surface prep for a structure like the Eiffel tower usually involves abrasive blasting. Controlling the dust even in the unlikely event there is no led paint requires tenting the structure.

I also have one of those singer sowing machines, probably the same model as Mr Baker. My bet is the frame is cast iron, rather good quality. There may be a high demand for artistic wrought iron (touched by a blacksmith), but there is no commercial source for actual wrought iron, and no active ASTM numbers for the material.

This company still sells wrought iron (recovered from scrap) in small lots. https://www.realwroughtiron.com/about-wrought-iron...

Well the Forth Bridge in scotland was supposed to have had a major paint job a few years ao, but took a long time and cost a small fortune. Given the complexity of the ET superstructure I would imagine it would be the same and you would need to encase it to stop all the old lead paint from polluting everywhere, presumably whilst they try to maintain tourist access... Won't make such a nice photo though when it's covers in scaffolding and plastic.

https://www.bbc.co.uk/news/uk-scotland-edinburgh-e...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

Many many years ago I did jobs for the rail ridge. Which is more similar to the tower.

The road bridge was a completely different set of on going nightmares

A very prolific bridge builder
https://duckduckgo.com/?q=bridges+designed+by+eifl...

A black swan to a turkey is a white swan to the butcher ... and to Boeing.

Quote:

Plan to visit ET in September, so hopefully, it will last at least until then

If it doesnt then we'd have a legitimate engineering disaster worth discussing.

I suspect COVID might screw you up more than corrosion the way things are going.

Quote:

I suspect COVID might screw you up more than corrosion the way things are going.

That's definitely a concern, given the rise in cases due to BA.1 and BA.2

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

We are on BA5 now in Europe.

Vaccines and previous infection to other variants make absolutely zero difference to your likelihood of catching it or the severity of symptoms.

The only thing is your less likely to get extreme fatal symptoms.

Apparently it's an utter swine to boot. And that's from someone who got alpha, delta and the first Omicron. And has just gone through this one. And he said he thought he was a goner this time because he felt so ill but his blood O2 stayed up. He said it was worse than malaria and lasted longer.

We finally just got hit by our COVID wave here at my job a few weeks ago. Oddly, I was one of two that didn't get it. But, an interesting observation is that everybody got symptoms. Half were more than mild. One ended up taking Paxlovid but fortunately didn't rebound like Fauci. That the asymptomatic rate doesn't align with the ~40% asymptomatic rate of past variants. I guess that's good news, we'll know when to stay home now.

I haven't tested positive for it. And my family have had it twice. Alpha and Omicron BA1.

There seems to be a link with blood group.

The guy I know who has had it 4 times now is AB+. My family the others are B+. I am O-. Don't know anyone who is O neg that has tested positive. But there isn't that many of us about.

Yes, I've read that people with type 'O' blood (RH factor is irrelevant) supposedly are less likely to contract COVID and if they do, they have a milder case. Note that I'm type 'O+' as are two of our sons (my wife is 'A+'). I've not had COVID, or if I did, I never knew it. Our oldest, one of the sons who is 'O+', has had COVID twice, and the other 'O+' son thinks he's had it, but it was so mild that he's not sure (he was never tested), but at the time, his wife was very sick with COVID and almost died (this was very early when there was nothing that they could do). Note that she's also 'A+'.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

The first time everyone got it during lock down 1 with alpha.

My brother in law aged 35 AB+ was extremely ill with it to the point of calling an ambulance. O2 was just above the red line so he stayed at home. 5days he was very sorry for himself.

Me I had a sweating 5 year old clinging to me for 18 hours. And was tested 3 times over the next two weeks negative every time. I might add said 5 year old the next morning got up at 8 ate 3 eggs a packet of bacon plus 4 slices of toast and 3 sausages and then put his snow suit on and legged it before his mother could ground him for being ill.

Which I got a bollocking for. Lunch was getting on for a kg of Shepard's pie I had made for that evening. I managed to prevent the afternoon grounding by pointing out the protein calorie load he had eaten in the last 6 hours he didn't seem very sick to me now. Plus being stuck inside with a load of sick adults when he could be sledging in the snow wasn't the best.

He demolished fries and bakebeans for dinner that night. And I was the only one who could smell the results of that diet thankfully.

I might add my bil still has issues which he didn't have before it. Although there could be a link to vodka consumption

I must be in triple figures getting my nose pulled through testing since it started. It's only in the last few months it hasn't been at least once a week.

All of that testing probably pulls the hairs from your nose which are your first line of defense.

Must admit there is a technique to minimise discomfort.

And a few cheeky comments limit the depth some are wanting to stick the swab in.

You can see the corrosion

Call me chickensh*t, but I still wear a mask when I go out... and, I don't go out often...

So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik