This video does not descripe the true hydration reactions of the Roman cement.. Roman cement is reaction between amorphous CAS material such as the pozzolana or GGBS and hydrated lime and an activator in the case of Roman cement and a crystalin material such as th tubomorite.. the binding strength of the Roman cement does not depends on the CSH crystal phase rather then it depends on the hexagonal crystalian phase.. these crysalian phases, the hexagonals, are the secret of the longgevity of Roman cement.. they do not undergo intrensic shrinkage after setting but most important they need high volume of water double the amount of water needed for the CSH crystals that found in Portland cement.. on top of that the left over of the hydrated lime will react with Carbonate to form a layer of calcium carbonate that will added to the overall strength of the concrete.. Roman cemmen does not suffer drying shrinkage like normal Portland cement because it absorb the extra added mixing water into its crystals, and does not develop drying shrinkage cracks like OPC concret ...that is its secret..

@ad1103

2 ай бұрын

If I wanted to build a stone house to last a thousand years, what mortar should I use between the stones to last a thousand years?

@TS-jm7jm

2 ай бұрын

​​@@ad1103 if i am not mistaken, roman concretes self healing comes from clasts of quicklime that are not totally mixed with the rest when it sets, so they have a core of quicklime sealed from the enviroment, thus when the concrete cracks, those cracks preferentially follow into the quicklime clasts, the quicklime being highly reactive, reacts with the water to flood and reseal the cracks and form calcite, this is helped by it being an exothermic reaction which means theoretically not all of the trapped quicklime clast is used up during the crack healing, you repeat this over a bunch of years as the concrete and structure settles more evenly, and the concrete would get stronger, i assume somesort of uneven mixing that mimics this would be the key to forming the mortar you want, key takeaway, quicklime not slakedlime, so straight from the lime kiln and hotmixed into mortar on site laid down there and then.

Great video! Thank you, i found it very useful and informative

If I wanted to build a stone house to last a thousand years, what mortar should I use between the stones to last a thousand years?

Sehr Gute Material Vielen Dank

Dr Mohammed Alhaj Hussein Roman pumice white or gray pumice ( amorphous pozzolanic material ) from بركان فيزوفس near pozzoli, مدينة بوزولي south Italy contain High content of SiO2 , and Al2O3. Roman cement is reaction between high quality of pumice powder and hydrated lime. The binding strength of the Roman cement does not depends only on the CSH, like normal Portland cement, it depend on the Sustainanle roman reaction CSAH.

@ad1103

2 ай бұрын

If I wanted to build a stone house to last a thousand years, what mortar should I use between the stones to last a thousand years?

Interesting could you do a video pozzlonic effects in plasters?

May you do a video over other ancient civilizations in the mortars that they use for example Egypt and also the Incas and also places in South East Asia

@KurtisHord

4 ай бұрын

It’s the same chemistry and period table the world around for 10k years. You’re either exploiting the quicklime reaction or the pozzolanic reaction or some combination of the two.. depending on your access to geology

@KurtisHord

4 ай бұрын

Wood ash cement or quicklime temped with the brick dust

Great video! I have a question regarding the superiority of the modern portlant cement. It has indeed proven itself by its wider use of course and its thermal expansion similar to the steel. Yet concrete made with portlant cement degrades rapidly and its durability is questionable. Its PPC's main ideas. It allows for extended durability as well as chemical resistance. Would you share your opinion on these facts. Also I read that the aggregate used by the romans had larger variety as well, effectively making rubble concrete.

@KurtisHord

4 ай бұрын

They are being sort of dishonest in saying modern concretes are “superior”. They might be superior at generating industry, but not as a building mortar and concrete technology. The first issue is them skipping from “Roman concrete” to modern hydraulic products: by volume of use, most human structures up to 1900 are hot mixed quicklime and earth. Sometimes modified with poz. The knowledge was never Roman. The only thing Roman was industrial scale and military application…. They did pick it up as one of their technologies, as every building culture did. It was used all thru the Middle Ages in the levant, china, France, etc. never Roman never lost. Always the main technology for human scale building. Plasters, mortars, and cast things.

@KurtisHord

4 ай бұрын

John Smeaton who was fully familiar with all manner of concrete chemistry and their use by craft guilds thru his recent history…. Writes from 1800, that “Roman concrete was lost”

@TheTransfix

4 ай бұрын

@@KurtisHord Thank you for your reply. Some interesting points that you bring up. I would take me time to reply categorically. I am not sure if they are dishonest in their assumption of the moderns concrete superiority. I am sure that if there is any mistake in their knowledge it is due to the information sources used. Nevertheless, in school we have learned about the ancient construction methods, although to be honest I do not remember half of that, and the point of the superiority of the portlant cement was its thermal expansion and strength and compatibility with steel; These all sum for the what, I think I understood you meant as generating industry. And about the romans, they surely did not invent the concrete but the way they made it popular one. I have read that the minoans used it for baths. Interesting point you bring up with the earth, I am not sure it will make same chemical bond with the lime as lets say crushed ceramic pots, vulcanic ash whatever (As is the one found in some places in germany). But all what you say is very interesting I would like to read about it if you can recommend smth. to me. For example I have read that the romans made a sort of rubble concrete out of it, making the mixture rathe dry compacting it and puting layers of stones; And also some brick separators (in some cases as external layer) every meter or so. Very similar to the middle ages wall construction (at least the one I've seen).

@KurtisHord

4 ай бұрын

@@TheTransfix so…. Understand the folks who invented engineering trades, had an agenda to say they were superior and craft practices of builders prior to them were not to be trusted. I am a builder that works with 9th century methods and materials. So I have my own agenda to promote human centered building knowledge rather than corporate or industrial

@KurtisHord

4 ай бұрын

@@TheTransfix the best scholar is dr Robyn Pender and the best chemist is Nigel copsey