Posted on 04/09/2023 11:30:54 AM PDT by Texas Fossil
Concrete is an incredibly useful and versatile building material on which not only today’s societies, but also the ancient Roman Empire was built. To this day Roman concrete structures can be found in mundane locations such as harbors, but also the Pantheon in Rome, which to this day forms the largest unreinforced concrete dome in existence at 43.3 meters diameter, and is in excellent condition despite being being nearly 1,900 years old.
Even as the Roman Empire fell and receded into what became the Byzantine – also known as the Eastern Roman – Empire and the world around these last remnants of Roman architecture changed and changed again, all of these concrete structures remained despite knowledge of how to construct structures like them being lost to the ages. Perhaps the most astounding thing is that even today our concrete isn’t nearly as durable, despite modern inventions such as reinforcing with rebar.
Reverse-engineering ancient Roman concrete has for decades now been the source of intense study and debate, with a recent paper by Linda M. Seymour and colleagues adding an important clue to the puzzle. Could so-called ‘hot mixing’, with pockets of reactive lime clasts inside the cured concrete provide self-healing properties?
Yes, Contrary to logic.
WPA Concrete seems to be much harder formula than we use today.
I remember a gymnasium floor that was poured locally, being cured for 28 days floated with water. You cannot imagine how hard it is today. My father was the many overseeing the construction company. Not as an employee, but representing the school. We lived directly adjacent to the school.
Dad was a very good contractor, residential and commercial. He was NOT an engineer, but he had good instincts and over built everything he ever touched. He was WWII vet, Belgium, Germany, and CZ. He died 2 years ago at 94. Great man.
So true.
It took leaving a block/tackle pulley on a tree limb and a stone with a cryptic message to launch not only a >2 century treasure hunt (i.e., ‘money pit’), but a potentially more valuable television series on the now-obscenely-expensive snipe hunt.
What an incredibly brilliant way to protect a treasure: Get everyone digging in the wrong place and make it impossible to prove otherwise.
I was intrigued by the series initially until I learned both the details and the fact that they continue to ignore both science & common sense in their ‘hunt’.
Puma Punku is real. How was it done?
There was a guy troweling the surface of a lump of concrete at a remote site. My dog walked over and plunked his front feet in about 8 inches of nice, wet concrete and watched the guy work the trowel. Dude looked over and made eye contact, said “ hi” to the dog, and went back to troweling. Took him about 30 seconds to figure out where doggie’s feet were.
I have discovered that some of the ancient technologies are much more advanced than our own, especially in the realm of moving and carving very heavy rock building blocks, etc. Wm. Shatner discusses much of this on his show “The Unexplained”.
And unfettered immigration.
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The best cement is placed not poured.
This was a three-sided (because that’s how many boards the guy found laying around), thick lump to hold a vertical pipe for supporting an antenna dish. It only had to be heavy.
Yep! Placed is the correct term.
Unfortunately I’ve seen, in passing, too many contractors that add so much water that pour is the reality.
I pity the owner.
The excuse I heard most when I was a inspector, “That’s the way we’ve always done it”.
I saw a video about that on YT.
For all the derision of ancient people, so many people forget that they not only did not have the advantage we do of building on other people work and knowledge base, they were the ones who discovered/created that knowledge base.
The genius it takes to figure out geometry and calculus and to build stuff we cannot fathom how they did it without machinery and calculators, etc, puts us to shame.
Nastiest jobs I ever had was working Concrete.
Setting forms for concrete walls and footers for residential homes or Building Custom Gunite (That’s Cement mixed with sand as the aggregate) for In-Ground Pools, Nasty work all around.
When setting forms for walls we’d occasionally miss the footers we had poured by an inch or less. The pressure from an 8 foot tall six inch wide wall of freshly pour concrete on the “gap” would cause a “Blow Out”. Concrete rapidly flowing outside of where it’s supposed to be.
Someone would Yell “Blowout, Blowout” !!!!
They would halt the pour from the mixer and next you’d hear, “Bucket Brigade, Bucket Brigade” !!!
The closest guy would jump into the hole to stop the blowout with whatever he could use. I’ve seen guys lay out their bodies in an effort to stop the blowout. You never really know how big the blowout can be, so you have to do whatever it takes. Concrete is expensive.
At the same time, all the workers on the perimeter are scrambling to find and throw 5 gallon buckets into the hole. At this point you’d have 2 or 3 guys in the hole scooping up concrete in the buckets and lifting them up to another guy straddling an 8 foot high wall/forms and he’d dump it right back into the form.
At the end of the day, every day, you would be covered in used motor oil and concrete from head to toe. The oil is used to keep the concrete from sticking to the forms.
Oh, and all that is mixed with dirt.
I found a great appreciation for Lava Soap.
By some very intelligent and ingenious human beings, who worked very hard.
I think the ones who insult them the most are the archeaologists who insist that they worked solely with sticks and stone chisels to carve out giant granite obelisks and things of the sort. They clearly had other tools or indeed it would be impossible within a single lifetime (we're talking about tombs in many cases so one lifetime is relevant). They consider the ancients to be kind of dumb. But whenever they find an artifact or structure that raises a question about that basic presumption, they declare it a religious item with no evidence or followup and move on like it doesn't exist.
There's much more to the ancients than we know. I don't buy much of the explanations of modern archaeologists as 'the truth' nor do I believe aliens came in and did it all.
The Donald had that turtle picture with the caption “Be Ungovernable”
This in turn reminds me of a science fiction story I read in one of the monthly digests about a ship from an interstellar empire that had dominated much of the galaxy and had set it's eyes on earth. They viewed it as a totally backwards and ignorant planet that one ship could easily subdue because they hadn't even mastered the simple technology of interstaller drive.
When they landed and emerged carrying their swords and flintlock pistols there were met with tanks and rifles and the captain realized that these natives had spent all their efforts on war and energy and communicatiosn but totally missed the one obvious thing that most civilizations discover early. Once they took the ship apart they'd instantly understand and then would become an unstoppable conquering force, he thought as he was led away in chains.
There are so many brilliant ideas that never made it because the person behind it lacked a way to get it out there, or it wasn't commercially viable in that specific time, or other reasons or simply ended in some catastrophe (think major volcanic eruption or ruinous war) and are now forgotten. From contemporary reports Archimedes alone had several things that to this day we cannot figure out how it would have worked.
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