If anything, the lime clasts were attributed to low quality, perhaps sloppy mixing practices, but they turned out to be the key to durability. Using quicklime a more reactive form of lime, the Romans reached high temperatures while mixing the concrete:
They just don’t make things like they used to…Pantheons included.
Almost everything built today is architectural garbage.
Great article but who would want a mall or a Walmart to last for centuries?
Todays political and social leaders are more intent on tearing down than building or preserving things of worth.
Population keeps expanding so need to have things for them
to do. Tare down, rebuild helps keep them employed.
I recall hearing about this quite a long time ago.
So they have discovered NOTHING. The use of pozzolan in concrete as a beneficial additive has been know for ages in the modern era.
Pozzolan / fly ash have been used in oilfield cements before began in the business nearly 50 years ago. It both decreases the permeability and somewhat lightens the mix. The benefit is dependent on the grind, the finer the better. Workability is also improved.
The only “discovery” in this is for Masic. Harvard tends to be a little slow on the uptake I guess.
Non-Union Labor?.................................
Found that at the end of the article. "Cancel culture" is insidious and evil.
99% of FReepers lack even a basic understanding of concrete. Doesn’t stop them from displaying their ignorance, however.
The Romans lacked both the knowledge about reinforcing steel and the ability to economically produce and transport it. Without it, the only path available to building the Pantheon was to use a super concrete.
Getting engineering info from a political blog is a serious mistake. And celebrating high temp mixes ignores all the risks that come along with it. I’m sure almost nobody commenting has ever heard of a flash set.
Typical FReepers getting their typing practice in.
I had always heard one ingrediant was the blood of slaves,,,
The Romans did not have unions interfering with construction.
Unions will never allow for the original method to be used. Building roads that last? Unthinkable! There goes one of their methods of keeping lasting employment…
Would love to see this translated into a set of easy-to-follow instructions. I’m building a house soon, and I want to make it as durable as possible.
I looked at the article too.
From the introduction:
“... method to reduce cement’s carbon footprint (which accounts for up to 8% of total global greenhouse gas emissions) ...”
What do greenhouse emissions have to do with the subject of the report? Nothing.
And it’s unbelievable that more recent concrete research hasn’t discovered those long lasting concrete formulations. I’ll bet today’s concrete experts know all about the use of ash, quicklime, and a lot of other ingredients.
The researchers behind the report used “a multiscale correlative elemental and chemical mapping approach”. Wowee!
Wine in Urine out