What Have The Romans Ever Done For Us?

[Flyfisher]

Well yes, obviously the roads . . . the roads go without saying. :wink:

But what about their long-lasting concrete . . . ?
http://www.bbc.co.uk/news/science-environment-40494248

 

[Feltwell]

They knew a thing or two about concrete did those Romans

https://en.wikipedia.org/wiki/Pantheon,_Rome

The properties of their pozzolanic concretes have been known about for a long time, so quite why it pops up on the news now I don't know.

I confess to knowing a bit about concrete. I once wrote a paper, many years ago, (under duress - I needed it to get my degree!) on corrosion inhibition in reinforced concrete. It won a prize from the Concrete Society. Amazingly, it didn't help me charm girls or get invites to the most outrageous student parties. Funny that. :wink:

 

[Andys]

According to the equivalent article in the Grauniad the Romans' concrete became more resilient over time when exposed to seawater. This was due to the formation of a crystalline substance called tobermorite within its microscopic cracks, a form of self-healing I suppose.

There followed a discussion in the comments area about whether it was also responsible for the hardness of Toblerone bars and its rumoured discovery by a litter collector from Wimbledon. I enjoy that kind of thing.

https://www.theguardian.com/science/2017/jul/04/why-roman-concrete-still-stands-strong-while-modern-version-decays

 

[Flyfisher]

Yes, I think it's the seawater angle that makes it newsworthy as they've just discovered the underlying mechanism. Interesting that it's being considered for the construction of the Swansea tidal lagoon - I wonder if anyone will actually risk it?

 

[88v8]

AIUI the main problem with concrete & seawater is corrosion of the reinforcement. But with the availability of stainless, that should surely be less of a problem? Although it would have to be A4, as A2 does corrode.

Recall in Iceland when I was there in 1983 there was a problem with the Hallgrimskirja
https://uk.pinterest.com/pin/377035800024132740/
a striking modernist building that was constructed of concrete, begun many years before but at that time unfinished, the rebars had rusted, and blown and extensively cracked the structure. It was eventually 'fixed' by cutting out the cracked concrete and coating the bars with epoxy, and opened in 1986, but how that will last in a marine environment, dunno.

The Romans were sitting on piles of pozzolan. For Swansea, it would have to be imported.

Ivor