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I was originally going to ask why it is we do not see more large-scale use of stainless steel for structural building members? I did a little looking and found there are some companies that sell stainless I beams:

http://www.pennstainless.com/stainless- ... cts/beams/

https://www.stainless-structurals.com/p ... eel-beams/

However, when I look at images of large scale modern buildings, it seems to me that they tend to use mild carbon steel and other alloys instead of stainless. Why is this? Is it because while the stainless is stronger, it can also then be more brittle? I would like all of you including metallurgists to give your answers to this.

I was thinking about that: Will we ever see entire large-scale buildings making i beams and plates and large-scale use of things like 440 series stainless or VG10 for these? What would the effect be?

It seems to me that using stainless may cost more at first but in the long term the maintenance costs would be lower because they are less prone to corrosion and do not have to be painted as much.

Why is this? Is it because while the stainless is stronger, it can also then be more brittle?

Stainless is not stronger and yes, it is more brittle.

I was thinking about that: Will we ever see entire large-scale buildings making i beams and plates and large-scale use of things like 440 series stainless or VG10 for these? What would the effect be?

It would be more expensive, less safe and more difficult to weld. There is no real upside and huge downside.

In general if no one is doing it there are usually good reasons why. The structural steels do not have anywhere near 1% carbon like the stainless steels you mention. Usually closer to .017 to .2 something carbon.

They have ways to coat and deal with corrosion in structural steels. Note they are using non stainless steels in ship building still so that shows corrosion can be managed.

Stainless steels have been used in things like cladding in buildings and monuments but that is different from structural use.

Joe

Why? Three letters! C O S T

You might see some Stainless sheets for cladding as an aesthetic or architectural feature....in those kinds of buildings that win awards for design from people with no appreciation of classical beauty.

But in the actual support structure? Not required and too expensive for the application

demoncase wrote: ↑

Sat May 25, 2019 3:36 pm

You might see some Stainless sheets for cladding as an aesthetic or architectural feature....in those kinds of buildings that win awards for design from people with no appreciation of classical beauty.

But in the actual support structure? Not required and too expensive for the application

Yes, like you and Mastiff pointed out, there are cladding for decoration on some buildings but the actual structural members seem to be low-carbon iron alloys/steel alloys.

demoncase, what would it take for this to change? Or, would it be an issue of "by the time advanced and inexpensive stainless alloys able to replace present structural steel came to be, we could make better materials such as composites for buildings."?

That being said, do you think we will ever see polymer and carbon and other forms of composites replace steel for bridges, such as suspension bridges, or not likely?

Here is a related question for you about cost in buildings: Is it the expense of finely-detailed architectural work that is behind the lack of much intricate artistic details on most modern residential and commercial buildings? Look at buildings made in the Victorian period and Edwardian era, in both the Americas and the UK, and see the intricate artistic details. And then after the WW1 period alot of that began to change.

SpyderEdgeForever wrote: ↑

Sat May 25, 2019 4:09 pm

demoncase wrote: ↑

Sat May 25, 2019 3:36 pm

You might see some Stainless sheets for cladding as an aesthetic or architectural feature....in those kinds of buildings that win awards for design from people with no appreciation of classical beauty.

But in the actual support structure? Not required and too expensive for the application

Yes, like you and Mastiff pointed out, there are cladding for decoration on some buildings but the actual structural members seem to be low-carbon iron alloys/steel alloys.

demoncase, what would it take for this to change? Or, would it be an issue of "by the time advanced and inexpensive stainless alloys able to replace present structural steel came to be, we could make better materials such as composites for buildings."?

That being said, do you think we will ever see polymer and carbon and other forms of composites replace steel for bridges, such as suspension bridges, or not likely?

Why does it need to change?....You've already got a material that's as cheap it can possibly be delivering the best results in the application.

There's no value to be gained from trying to make stainless surplant basic structural steels. There's no problem to solve here so I'd forget it and move on.

Could fibre-reinforced polymers replace steel in bridges?.....Sure- on the day you built it.

But can fibre-reinforced polymers last as well outside in all seasons, cycling both thermally (winter to summer) and physically (with loading and winds)?....I've driven across suspension bridges that are 200 years old. I've driven across stone bridges 500 years old.....I doubt that an entirely polymer bridge would maintain structural stability for that length of time.

SpyderEdgeForever wrote: ↑

Sat May 25, 2019 4:11 pm

Here is a related question for you about cost in buildings: Is it the expense of finely-detailed architectural work that is behind the lack of much intricate artistic details on most modern residential and commercial buildings? Look at buildings made in the Victorian period and Edwardian era, in both the Americas and the UK, and see the intricate artistic details. And then after the WW1 period alot of that began to change.

That's more about the design aesthetic of the time....When rebuilding after WW1 the modernist architects wanted to sweep away the 'fussy' Victorian styles with clean, simple lines- and the new ability to cast concrete gave them a medium for that

Equally, the Victorians obsession with ornamentation and detail was about showing what they could do with the cast iron materials of the time- sweeping away the 'oriental obsessions' of the Georgians before them. (Brighton Pavillion for a great example- Prince George built himself an India palace and plonked down on the south coast of England https://en.wikipedia.org/wiki/Royal_Pavilion)

Being a Brit and surrounded by examples of each of these architectural styles of the last 500 years in even my own humble home town, I can see each style has it's benefits and each has it's limitations.....apart from the lumpen, brutalist Stalin-esque concrete of the 1960s which deserves to be forgotten

What an excellent analysis of the situation, demoncase. Thank you!

And here is a somewhat related question: If an American or Australian or other person wanted to visit an English village or small town that had the "feel" of an old-time Victorian or before village but also with access to modern conveniences and things like that, what would you suggest?

SpyderEdgeForever wrote: ↑

Mon May 27, 2019 1:57 pm

What an excellent analysis of the situation, demoncase. Thank you!

And here is a somewhat related question: If an American or Australian or other person wanted to visit an English village or small town that had the "feel" of an old-time Victorian or before village but also with access to modern conveniences and things like that, what would you suggest?

Buy a plane ticket to any UK city except London
Land
Get a train ticket to the nearest small town or village.
Ignore the kebab shop and Bet Fred.....and done!

Or to see a truly preserved piece of the time repeat the above and head to the Black Country Living history museum in Dudley.
(Google it)

The friction created by the light corrosion on connected steel members also has a significant role in bolted structural connections - the bolts clamp rather than simply peg. (The same if embedded as reinforcement in concrete). Bolted connections in shiny stainless would be weaker, and welding stainless steel is more problematic than welding “normal” steels, particularly in typical building site conditions, I would imagine.

Several 1930’s steel framed seafront apartment blocks here in Brighton have suffered real - and very costly - problems of corrosion to their hidden structures, and new blocks are still erected in basically the same fashion.