Engineers Weigh Up Returning to #Ancient #RomanConcrete Recipes

Carly Cassella
Wed, July 30, 2025

"The ancient Romans might have taught us a thing or two about manufacturing #sustainable concrete that lasts for thousands of years.

"A new study has rigorously analyzed the raw materials and energy demands of their ancient recipe, revealing some useful ways to improve modern cement.

"Surprisingly, researchers found that producing Roman mortar and concrete requires more water and more greenhouse gas emissions than #PortlandCement – the most common type of cement used in concrete today.

"But while the initial energy costs may be steeper, Roman concrete formulations could ultimately prove more sustainable in the long run. That's because they may not need to be replaced or repaired as often."

Read more:
https://www.yahoo.com/news/articles/engineers-weigh-returning-ancient-roman-150048862.html

#Infrastructure #BuildingSustainably #MadeToLast #AncientTechnology #Concrete

The Road to #LowCarbon #Concrete

For thousands of years, humanity has had a love affair with cement and concrete. But now, industry groups and researchers are seeking solutions to the huge amounts of carbon dioxide that cement-making generates.

M. Mitchell Waldrop, November 16, 2022

Excerpt: " To tackle the other 60 percent of cement emissions — the CO2 that’s released on the right-hand side of the calcination reaction — the industry is beginning to revive some old alternatives for cement’s raw materials.

"Simply by adding some powdered, unbaked limestone to its final product, for example, a kiln’s carbon footprint can be reduced as much as 10 percent. (Limestone alone is relatively inert but will help Portland cement harden when it’s mixed with water.) This Portland-limestone cement is already commonly used in Europe and is now taking off in the United States. 'We’re seeing regions of the country where Portland-limestone cements are the predominant material and we’re hearing individual plants say that they’re only going to produce this type from now on,' Bohan says.

"Kiln operators are also taking a fresh look at replacing some of their limestone-based cement with mineral-rich industrial waste products. One commonly used example is blast-furnace slag from steel mills, which is rich in calcium and hardens like standard cement when it’s mixed with water. Another is fly ash from coal-fired power plants, which doesn’t harden on its own, but does when it’s mixed with water and standard cement. Either way, the resulting cement yields concrete that is at least as strong and durable as the standard variety, if somewhat more abrasive and slower to cure, while potentially trimming emissions by another 15 or even 20 percent.

"Granted, there was a lot of carbon dioxide emitted during the original creation of these wastes. But using them in cement doesn’t produce any new carbon. And two-plus centuries of industrialization have left a substantial backlog of slag and ash, even if we eventually phase out coal entirely. 'It’s a win-win. If you have the waste, then replacing your clinker with it is cheaper than producing new clinker,' says Andrew. Indeed, this technique is already widely used in fast-growing countries like Brazil and China, which are producing mountains of slag and ash as they build up their industries. "

https://getpocket.com/explore/item/the-road-to-low-carbon-concrete?utm_source=firefox-newtab-en-us

#Cement #Buildings #Infrastructure #PortlandCement #CarbonFootprint