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How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

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Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#151

Post by justin66 »

demosthanos wrote: post #6

Related, Grady Hillhouse on the myth of Roman concrete. > The miracle of modern chemistry has given us a wide variety of admixtures like superplasticizers to improve the characteristics of concrete beyond a Roman engineer’s wildest dreams. So why does it seem that our concrete doesn’t last nearly as long as it should? It’s a complicated question, but one answer is economics. There’s a famous quote that says “Anyone c…

This is a good link and the Practical Engineering guy doesn’t appear to reference a “myth.” Which is a good thing, because there’s nothing mythological about the high performance of Roman concrete.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#152

Post by andsoitis »

rewtraw wrote: post #147

we can't figure out roman concrete we don't know how ancient megaliths were built centuries old cathedrals and holy places have more intricate masonry and carvings than anything built today (with allegedly more primitive tech) are historians retarded? what's going on here? time is flowing backwards and civilization is declining, but humanity is under a collective trance and can't even see it.

> time is flowing backwards and civilization is declining

Why do you think civilization is declining?

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#153

Post by andsoitis »

Cthulhu_ wrote: post #59
somenameforme wrote: post #42

Earlier quoted context omitted.

I don't see how this would work because you're saying that the older sidewalks are scrapped and rebuilt when they hit a state of 'x' deterioration, so you only see > 'x' state ones. But how then could it be that newer sidewalks are allowed to fall below 'x' instead of also just being scrapped and rebuilt?

Politics, money allocation, taxation, etc. The US had a golden age last century and is now in decline. It can still bounce back but it needs a political and legal revolution, in this particular case, it needs to tax the wealthy and spend it on municipal improvements. But that's socialism / liberalism and apparently that's terrorism now.

> it needs to tax the wealthy

The top 1% of earners pay about 38% of all federal individual income taxes, while making up roughly 20% of the nation's total Adjusted Gross Income.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#154

Post by iknownothow »

tpm wrote: post #128
gravypod wrote: post #116

Earlier quoted context omitted.

Neither is grout. Grout is water permiable. You shower is water proof from the water proof backing we install the tile on top of. Cement board + roll on or something like kerdi system. https://youtu.be/B5DVpruLygw?si=jD8eMHHGQoWG4hI2

right, but lime will be washed away by the water if no waterproof layer is added

It is not lime as in the fruit, it is lime as in the material (CaOH2). Lime the material is the binding agent in lime plasters. It is not likely to get washed away.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#155

Post by cindyllm »

andsoitis wrote: post #153
Cthulhu_ wrote: post #59

Earlier quoted context omitted.

Politics, money allocation, taxation, etc. The US had a golden age last century and is now in decline. It can still bounce back but it needs a political and legal revolution, in this particular case, it needs to tax the wealthy and spend it on municipal improvements. But that's socialism / liberalism and apparently that's terrorism now.

> it needs to tax the wealthy The top 1% of earners pay about 38% of all federal individual income taxes, while making up roughly 20% of the nation's total Adjusted Gross Income.

[dead]

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#156

Post by Mistletoe »

toasty228 wrote: post #52
Mistletoe wrote: post #7

I’ve often wondered why every good sidewalk I see has a WPA stamp on it from the 1930s and the modern ones are all crumbled and uneven. https://share.gemini.google/5g0gxGyOmAPD

Don't you love it when gemini quotes an AI generated video with 83 views as a source of truth

I'm also judging by my own eyes because I can see that the WPA concrete uses coarser substrate like the Gemini answer says and is harder than normal concrete when I press it. And also has no cracks in it almost 100 years later.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#157

Post by rkangel »

PunchyHamster wrote: post #79
rkangel wrote: post #73

Earlier quoted context omitted.

A broader view of this point would be "the economic structures in some countries do not allow for investments with a long payback".

Or simpler: people don't exactly want a house layout that was popular 100 years ago. And definitely not the level of insulation it provided. Nor the fact putting any new wiring and piping thru concrete is PITA Tastes change and so do other requirements. but , if we actually built for longevity in use, we could build a very durable shell of a house and then use more perishable but easier to modify methods for inside.…

In my area of the UK at least, the house layouts of houses built last year aren't appreciably different from those built 200 years ago. That's specifically comparing detached and semi-detached houses. Terraces are a bit different now.

> then use wood and plasterboard for room walls and floor

One of the things I LIKE about older houses is that the interior walls are more solid than plasterboard. There is zero plasterboard in my house and brick gives far better noise insulation than anything timber framed.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#158

Post by rkangel »

freedomben wrote: post #141
rkangel wrote: post #82

Earlier quoted context omitted.

There are some downsides, but most people on the UK would prefer houses that were 100+ years old. In the village I live in the houses immediately around me are "only" 50 years old. Most of the ones on the main street are well over 100 years old. Housing tastes don't really change that much. Yes over the years we've had to fit things like double glazing and better insulation but that's a whole lot cheaper (and better…

> but most people on the UK would prefer houses that were 100+ years old. Why do most people prefer older houses?

I think two reasons:

Character and history - they tend to be more individual and different, and have more character than the cookie cutter modern mass builds.

Solidity - they tend to be more stone and brick, instead of the timber framed buildings that are more common in new builds.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#159

Post by mikepurvis »

Modified3019 wrote: post #55
mikepurvis wrote: post #26

Earlier quoted context omitted.

To build without tension you have to build structures that basically look like Roman structures [1]: a bunch of tightly spaces arches so that the entire thing is in compression, with no meaningful tension anywhere. But it turns out that's pretty inconvenient; we really like doing dozens of feet of span for highway overpasses, building floors, and everything else. So we put rebar in all the concrete and just acknowled…

The “it’s built so everything is under compression” is great thing to bring up, but fyi your link is AI generated, filled with senseless repetition and “it’s not just x, it’s y”. Looking it up on archive.org shows it was generated this year.

Blah, so you're right. I was just looking for a link with some representative reference pictures, but I should have done more diligence. Thanks for pointing it out.

Re: How Has Roman Concrete Lasted for Millennia? 1,900-Year-Old Latrine Offers Clues

#160

Post by kps »

beeforpork wrote: post #76
Barbing wrote: post #23

Earlier quoted context omitted.

Like the plate of food on the grass for the bees at the barbecue

Wasps, not bees. (Sorry, I'm a bit of a nerd. But I am sure you can cope with that.)

Does pork factor into this? (Serious question for an expert, not a joke.)
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