Roman concrete … should we do hot pours?

[JoyfulNoise]

Now this is some fun science -

Riddle solved: Why was Roman concrete so durable?

Researchers have discovered ancient Roman concrete-manufacturing strategies that incorporated self-healing. Applying this knowledge toward modern cement production, they hope to improve the material’s environmental impact.

news.mit.edu

I’m a big fan of going back to adding pozzolans and asbestos to all my concrete work!! And now I just need to get a rig setup to do “hot pours”!! If it’s good enough for the Romans, then it’s good enough for me … plus I think I look pretty good in a tunic

 

[Turbo1Ton]

--Jeff

 

[Schwimmbad]

Don’t forget your quicklime, and does this put an end to new owners bonding with their pool?

 

[YippeeSkippy]

Researchers also found that the mortar in the Great Wall of China contains rice flour. They found that is the miracle that helped keep it together all these years. Cool, huh?

 

[JoyfulNoise]

Researchers also found that the mortar in the Great Wall of China contains rice flour. They found that is the miracle that helped keep it together all these years. Cool, huh?

And rice flour is the key to good banana fritters as well …

 

[phonedave]

Now this is some fun science -

Riddle solved: Why was Roman concrete so durable?

Researchers have discovered ancient Roman concrete-manufacturing strategies that incorporated self-healing. Applying this knowledge toward modern cement production, they hope to improve the material’s environmental impact.

news.mit.edu

I’m a big fan of going back to adding pozzolans and asbestos to all my concrete work!! And now I just need to get a rig setup to do “hot pours”!! If it’s good enough for the Romans, then it’s good enough for me … plus I think I look pretty good in a tunic

Fly ash (a pozzolan) is a common admixture. In fact the base mix in the study used fly ash.: OPC, pulverized fly ash, sand, and water at a mass mixing ratio of 1:0.2:2:1 with between 7.5% to 15% by mass of quicklime (so you can mix up your own). It does get pretty hot. The temperature increase in the mortar is approximately 55° to 60°C over ambient, with a presence of hot spots characterized by temperatures exceeding 200°C

It appears it is a combination of the quicklime and the high temperatures that form the lime clasts that are responsible for supplying the calcium to react with the pozzolanic material to self heal cracks.

That was a really cool experiment. Reinforced concrete lab was one of my favorites, where else could you mix gantry cranes and steel work with chemistry (and then breaking things in hydraulic presses)

 

[Jaffles]

Now this is some fun science -

Riddle solved: Why was Roman concrete so durable?

Researchers have discovered ancient Roman concrete-manufacturing strategies that incorporated self-healing. Applying this knowledge toward modern cement production, they hope to improve the material’s environmental impact.

news.mit.edu

I’m a big fan of going back to adding pozzolans and asbestos to all my concrete work!! And now I just need to get a rig setup to do “hot pours”!! If it’s good enough for the Romans, then it’s good enough for me … plus I think I look pretty good in a tunic

Not sure what you do Joyful, but good on you giving a rip to make something last.
I discovered the view of my pool builder was pools are likes cars these days, 10 years and its time to upgrade. I was hoping for at least 20 to 30 years. Don't think I'm moving.

 

[phonedave]

Not sure what you do Joyful, but good on you giving a rip to make something last.
I discovered the view of my pool builder was pools are likes cars these days, 10 years and its time to upgrade. I was hoping for at least 20 to 30 years. Don't think I'm moving.

For the record, self healing concrete has been around for a decade, if not more. It has to with the inclusion of various admixtures - mainly fly ash and silica fume and then grinding everything up into a fine powered using specialized mills. High Mixing Energy Concrete. Basically you beat the every lovin' daylights out of the cement mix before you add water.

However, as to how the Romans did it was previously a mystery. Apparently they just added unslaked lime, which caused high temperature areas that form lime clasts. The interesting thing is, that people knew High Mixing Energy works, and they have been reporting that it creates high temperature hot spots in the mix as well. Now somebody put two and two together.