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Can We Live Without Concrete? (cnn.com)
A combination of cement, water and ground rock or sand, on the surface concrete might seem crushingly mundane. Yet it has defined construction in recent centuries and with it, in part, modernity. From a report: But do we need to re-evaluate our concrete habit for our sakes and the planet's? Production of cement is disastrous for our biosphere, while the degradation of many concrete buildings has some construction experts predicting a colossal headache in the future. There are myriad proposed solutions, such as changing the way we make concrete, creating sustainable alternatives or doing away with it altogether. But would we want to live in a world without concrete? And what would that world look like?
"We make more concrete than anything else, any other product, apart from clean water," says Paul Fennell, professor of clean energy at Imperial College London. One 2015 report estimates that each year approximately three tons of concrete are used for every person on Earth -- roughly, 22 billion tons. To put that in context, a recent study estimated that 8.3 billion metric tons of plastic have been produced, ever. Manufacturing cement, concrete's binding agent, is energy-intensive, Fennell says. Ordinary Portland cement -- the most common form in concrete -- is produced by baking lime in a kiln and emits approximately one ton of carbon dioxide for every ton of cement. Concrete production is responsible for approximately 5% of global man-made CO2 emissions, according to the World Business Council for Sustainable Development.
"We make more concrete than anything else, any other product, apart from clean water," says Paul Fennell, professor of clean energy at Imperial College London. One 2015 report estimates that each year approximately three tons of concrete are used for every person on Earth -- roughly, 22 billion tons. To put that in context, a recent study estimated that 8.3 billion metric tons of plastic have been produced, ever. Manufacturing cement, concrete's binding agent, is energy-intensive, Fennell says. Ordinary Portland cement -- the most common form in concrete -- is produced by baking lime in a kiln and emits approximately one ton of carbon dioxide for every ton of cement. Concrete production is responsible for approximately 5% of global man-made CO2 emissions, according to the World Business Council for Sustainable Development.
Can't live with it, can't live inside it.
Almost as much bullshit and low quality in the premise of this posting as asphalt and the whole asphalt lobbying and astroturfing.
Concrete is heavy, and plastic is light. So by weight, it seems reasonable that "we" produce more concrete than plastic.
Is that why there's more gold produced than concrete?
Hemp is a good alternative to concrete. In addition it is renewable and extracts Co2. Plus it makes other useful things like clothing. Unfortunately the cotton industry is preventing the world from growing it. It is those people that are preventing us from having buildings made from hemp today.
Yeah, nah.
Slashdot: providing anti-social weirdos a soapbox, since 1997.
Ergo, humanity must not exist, since we could not have existed before concrete.
The truth is probably somewhere in the middle. Some of us could have existed, others not. To understand why, ask yourself: What was the human population before the invention of concrete, and what is the human population now? At least some of this additional carrying capacity probably arises from inventions that rely on concrete.
Comment removed based on user account deletion
Why do you propose changes to make everyone's life worse?
Figure out a way for life to actually be better. That's what you did in the 1970s when there was air pollution and water pollution. Air pollution was a problem, not a fear about a possible problem.
Fund some research to create something better than concrete if you want something better than concrete.
Don't ask us to give up living modern lives and mire ourselves in artificial poverty. That's not something Americans or Asians will do. Europeans might.
Sorry. We're too dependent on it as a building material.
Now, this doesn't mean we can't modify concrete to reduce/eliminate some of it's deleterious effects on the environment.
But, in the end, we still need concrete in whatever forms it eventually takes.
Chas - The one, the only.
THANK GOD!!!
Concrete is the reason we can build things higher than four stories.
Silly me.. Here I thought that was steel and elevators that did that.
Concrete is nearly useless without steel. Huge compression strength, itty-bitty tension strength. Yea, you can pile up blocks of concrete and "build something" but without steel you won't be able to do much more than a pyramid.
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
The crux of the article was Rammed Earth, which I think is a great replacement for concrete for certain applications (some load-bearing vertical walls mainly). Dirt cheap, clay & sand.
Some applications of concrete are frivolous and I think can be replaced. The reason is mostly cost and availability, and the current labor force is skilled with using it. The wall-facade material of choice before concrete, and before gypsum drywall, was Lime plaster. For wet or exterior applications I am in favor of using lime as it is less carbon-intensive than concrete and produces a beautiful lighting effect from birefringence (https://en.wikipedia.org/wiki/Birefringence), owing to the tiny calcite crystals that form when it cures back into limestone. See http://www.sapphireelmtravel.com/travel-journal/chefchaouen-morocco-blue-city for an example.
There's also benefits to the water vapor breathability of lime vs. concrete (which doesn't breathe, unless it's cracked).
Producing Lime plaster is less carbon-intensive than cement as it requires lower temperatures, and the CO2 driven off by the limestone during calcining (which happens in Ordinary Portland Cement production as well) is mostly re-absorbed by the slaked lime as it cures back into limestone (leaving the net CO2 footprint coming from the fuel used to calcine the lime, if coal or natural gas or wood is used, although perhaps decades into the future someone comes up with a nuclear-fueled kiln, electric or high temp gas or whatever).
The big downside to lime plaster is the time it takes to cure, and what that does for timelines and labor costs. It usually requires multiple thin coats (with a week or more between =3/8 inch coats - need time for CO2 to reabsorb as carbonic acid which also requires the material be damp, but not covered in water) which blows up the labor costs.
https://johnspeweik.com/2011/10/27/the-lime-cycle/
The upside to using lime plaster is there's a wealth of historical information on what to do with it... much of the "bling" of the pre-1800's architecture can be traced to the use of lime or limestone.
E.g. the Moroccan process of Tadelakt - https://en.wikipedia.org/wiki/Tadelakt
Venetian plaster - https://www.architecturaldigest.com/story/venetian-plaster-trend-guide
the real at&t mix
They are starting to build wooden skyscrapers http://www.bbc.com/future/stor...
"The hands that help are better far than lips that pray." - Robert Ingersoll (1833-1899)
FIVE PERCENT of global CO2 emissions for cement production. Reinforced is one of the most useful, versatile, and inexpensive construction materials we have devised. I wish to reduce co2 emissions - targeting something that far down the stack seems stupid to me given its utility. Much better gains in CO2 reduction can be made elsewhere (power generation and transportation).
Silence is a state of mime.
The post is based on a false premise: that CO2 production is inherent in making concrete. There is already a process to not do that. Further, most of the CO2 is made from generating the heat to make the concrete. Most of that CO2 production is low-hanging fruit to eliminate.
This is just more chicken little chicken shit.
Sorry, forgot the link:
https://phys.org/news/2012-04-...
The lime emits CO2 as CaCO3 converts to CaO. It does not absorb back into the material in the use-case of Portland Cement.
Lime plaster, which I posted about further down, DOES bring that CO2 back into the material (as it cures by Ca(OH)2 converting back to CaCO3+H2O with the introduction of carbonic acid, i.e. CO2 dissolved in a thin film of water).
the real at&t mix
They compared concrete to plastic, but most of the weight (about 85%) in concrete is sand and rock. Although even with that the world uses a lot of cement.
Rather than looking for alternatives I'm guessing this is a plea to make the manufacture of cement more environmentally friendly (green energy for the heat, capture the CO2, etc.). That would make far more sense than trying to find an alternative to concrete.
The Colosseum, at "only" 15 stories high, waves in your direction. You can use stone in place of steel quite well...
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
It's called indentured servitude to the state.
When you depend on the state, you will vote to empower the state to hold power over you. Because, no longer will people vote out of optimism of choice, rather, out of fear of having their state provided "benefits" taken away.
Life is not for the lazy.
"Concrete is as good as stone, and you see how long ancient Greek, Roman, and Egyptian stone structures have stood. "
The Romans built almost everything with concrete, also the 'stone' structures you mean. The stone was usually only a thin outer shell to contain the poured concrete.
Also their concrete was (and is) much more resilient, it didn't crack as easily as our Portland variant. Portland cement wouldn't last for millennia, it sometimes doesn't take decades to make it fail.
"Recently, it has been found that it materially differs in several ways from modern concrete which is based on Portland cement. Roman concrete is durable due to its incorporation of volcanic ash, which prevents cracks from spreading."
https://en.wikipedia.org/wiki/...
Betteridge's law is about the possibility of "excitement", it works on titles with the form "could it be exiting?" (the answer is no). This title is almost the opposite, concrete is so normal that we wouldn't even think of a world without it so the question is reversed, "would it boring if we stopped doing this normal thing" is used instead. This trick relies on peoples assumption that changing the status quo will be big and "exiting", when normally it is boring, guiding people into assuming an exiting answer. A slightly more complex rule that works for both is - when a title asks a question, with a yes/no answer, the answer is the boring one.
In this case there are already polymer resin based substitutes, so any change in cost/availability of gypsum cement big enough to stop the use of concrete will instead cause a small change in building appearance and in the long run not much else
We use concrete because concrete is cheap. Really, really, cheap. You can get similar results with other materials for many applications but there are few materials that are as readily available, easy to use, and inexpensive as concrete. Come up with a material with usable performance and a similarly low price point and you can be sure we would use a lot of that.
FYI one ton of concrete is a piece roughly 0.42m^3. So they are saying we each use a piece of concrete about the size of a desk each year.
FIVE PERCENT of global CO2 emissions for cement production.
Captain pedantic here but it is NOT cement. It is concrete and they are not the same thing. Every time you conflate the two terms a civil engineer looses his wings. Cement is an ingredient in concrete but concrete is not cement.
Most of the time you move concrete thrice. Once to get the components to where it is being 'made', and again to get it where it is being used.
And after a while, you may, may remove it and either recycle or dispose of it.
Transportation costs are a real thing, but in this instance I doubt these costs are such a big deal. Now steel has advantages, perhaps, in production costs and recycling, but sometimes you need strength and mass, and until we rethink design, concrete is the solution.
deleting the extra space after periods so i can stay relevant, yeah.
Elevators are the reason we want to build things more than four stories high.
deleting the extra space after periods so i can stay relevant, yeah.
Believe it or not it has to do with sand.
Sand with sharp edges.
Sand from the desert is round and is not good for cement.
So stop worrying about the CO2, energy, etc needed to make cement. we are running out of sand.
https://science.slashdot.org/s...
http://www.spiegel.de/internat...
https://www.npr.org/2017/07/21...
IOW: we are fsked. Roads, buildings, bridges, etc will have to be built with something else and nobody cares to even worry.
Obama's legacy: (N)othing (S)ecure (A)nywhere and (T)error (S)imulation (A)dministration
When I was little, I was told a house made of strawbale and another made of wood failed to survive severe weather, particularly strong rain[1] and wind.[2] Or have I been duped all these years by the brick construction lobby?
[1] "The Pros and Cons of Straw Bale Wall Construction In Green Building"
[2] "The Three Little Pigs" by Joseph Jacobs
Like all things environmental.
What are the alternatives? Wood, Bricks, Stone...
What are the Pros vs Cons of these alternatives? Renewable, Deforestation, difficult to ship, difficult to work with, limitation on what can be made...
Can a hybrid approach be done? Are we using more Concrete then we need? Do we really expect this building to span the Melania?
Where I live there is an abandoned factory made from Concrete, it is an eye sore in the city. However it is nearly indestructible, and will cost too much to knock down.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
If we could teach AI to quarry, transport, shape and stack rocks at least as well as humans did in the 17th century, we could literally build castles (and bridges and aquaducts) with very little energy input. Rocks are everywhere, and an army of AI powered instruments could be programmed to improve on the work of even the best stonemasons: If they scanned each available stone that comes from a quarry, algorithms could design the optimal stacking arrangements to minimize gaps and maximize structure stability. They could "solve" a construction project like it's a giant 3D puzzle, thus minimizing the number of stones that would need to be chiseled. But even chiseling stone with machines uses very little energy. The pace of construction would only be limited by the number of autonomous tools brought to bear, and they themselves could turn out to be cheap and mass-producible. Sure, you can't build skyscrapers from rocks, but I would happily live in a city of six story rowhouse blocks built from stone. The neighborhoods in Europe that are actually built in this way are beautiful, functional and pleasant to live in. With AI building tools that sink the cost of labor to almost zero, I think we should explore returning to some of these old, well-tested building methods and architectural designs.
St. Peter's Basilica's central dome doesn't use steel - and it has a ~42m clear span in the middle. You don't have to have something "narrow" because you're not using steel. Just good geometry that puts a quality building material mainly in compression. And it works REALLY well. You do need height when you do an arch - but building 2-3 stories of wood floors inside a given archway isn't really much of a challenge, is it?
Browsing at +1 - no ACs, I ignore their posts. So refreshing!
as far as I can tell, this summary is blaming concrete because the energy source is dirty. What if the energy came solely from turbines, dams, nuclear power, or some other form of clean energy?
Here's the thing. The reason that the "energy source is dirty" is because there's a whole pile of stuff we don't recycle(it's too expensive, or too dangerous, or too hazardous and so on), in turn we use during the making of cement. Tires, some plastics, medical waste, non-recycled automobile fluids, various hazardous compounds from industry just to name a few, it's all used as fuel and scrubbed to reduce emissions when you're baking the lime. The remainder ash(fly ash) is mixed in with the cement in various grades and this improves the quality of the cement itself, the fly ash itself is cheaper then digging raw materials or importing them.
Seriously, we're pretty good at using things in a full cycle these days. If you think that it's cheaper to import metric tonnes of sand/clay/shale halfway across the country after digging it up, then to use an available material you can make during the kiln process? Well you're gonna make some serious money. It's kinda like the people who whine about paper and wood products, but don't realize we have a fully sustainable harvest cycle.
Om, nomnomnom...
Even worse:
each year approximately three tons of concrete are used for every person on Earth -- roughly, 22 billion tons.
Every year we are adding 22 Billion tons to the weight of the earth. Sooner or later, that's going to start having an effect.
The words "set to", "will", "planning", and "plans" come up a lot that article. They aren't going to build it for another 20 years, and it's anticipated to cost twice as much as a conventional high-rise.
Granted, there is a link in the bottom of that story to an existing wooden building that is 18 stories tall. It's in Vancouver. Notice what's at the core of that building? Two giant concrete towers. Underneath it? A concrete pedestal. GP's point stands as stated.
I'm confused, why would the parasitic rich want to solve the parasite problem?
--- Most topics have many sides worth arguing, allow me to take one opposite you.
as far as I can tell, this summary is blaming concrete because the energy source is dirty. What if the energy came solely from turbines, dams, nuclear power, or some other form of clean energy?
Fossil fuel combustion is only part (40-50%) of the problem with making cement. The other part, 50-60% is this chemical reaction: CaCO3 -> CaO + CO2. The calcium oxide produced is a key part of cement. Not using fossil fuels would cut CO2 emission by about half, but is not a complete solution to the problem.
Actually cement - over the course of decades - reabsorbs about 40% of the CO2 released by the burning of limestone as it post-cures. So the net CO2 release from concrete is commonly overstated by about 20-25%, and the net contribution of fossil fuel is more like 55-65% of total net CO2 release.
Second class citizen of the New Gilded Age
There is a mythconception touted by some that concrete is bad. That is totally wrong. Concrete is almost all rock and sand. There is very little cement (the material at issue) in it. And the long term net effect is that concrete is a benefit because concrete structures last for a very long time, measured in hundreds to thousands of years as opposed to wood built structures that last mere decades.
Additionally, if you properly design your structures you can make concrete even greener by eliminating the need to heat or cool the buildings. I have done this with both our home and our butcher shop. Concrete offers tremendous thermal mass which can store the heat from summer over to winter to keep the building warm and store the cold from winter over to summer to keep the building cool.
I have done this with our home which masses about 100,000 lbs inside an insulated envelope. Even in our extreme cold climate in the central mountains of northern Vermont we don't have to heat or cool our house. It will stay in the mid-40's through the winter and rise to the 60's in the summers. We can optionally raise that to the mid-70's in the winter with just 0.75 cord of wood (a very small amount for those of you who don't use wood heat), which is a renewable resource from dead wood on our land.
Our butcher shop is built along the same lines but far more massive at 1.6 million pounds of concrete built in six shells with insulation between each. We have no heating system and no refrigeration system to chill our cutting room, etc. We've been operating for three years under Vermont state inspection and on May 1st we received our USDA license. I've been told repeatedly by the USDA and other government officials that they are amazed by our facility because it is so good, requires so little maintenance, is so easily cleaned and how it naturally stays the right temperatures. All of that is about design. I love math. Math applied is even better - it solves real problems.
Concrete is not evil and is not the cause of global warming. Properly used concrete and cement are the solution to reducing pollution and cutting energy consumption.
Concrete is heavy, and plastic is light. So by weight, it seems reasonable that "we" produce more concrete than plastic.
Is that why there's more gold produced than concrete?
I don't think we produce any gold. The alchemists lost.
"That's the way to do it" - Punch
All we have to do is move back into caves which is what the eco extremists really want.for everyone but themselves ...
On second thought, I believe they want we, the unwashed masses to move back into trees and to forget that we know how to make fire.
Yeah ... that's it !
Sorry, but we *don't* have a fully sustainable harvest cycle. We're getting a lot better, but we still need to improve a lot. During parts of the cycle there's a lot of soil erosion. It's still not clear how many times we can run through the cycle on a particular plot of land before wearing it out. And that's when there aren't any problems, like, say, pine beetles moving into a new area. Or droughts combined with fires.
Sorry, but we do. Why don't you go take a trip and find out for yourself. I'll remind you that the problems of "pine beetles" and "droughts and fires" are caused by current policies where they don't allow direct burns, but rush to put out fires. Which furthers the problem of accumulated ground material that's highly flammable. I mean, I've seen areas here in Western Canada where the ground clutter is over 3' deep and there hasn't been any burning done in 80 years.
Om, nomnomnom...
Environmentalists want us to live
Billionaire concrete tower makers?
Not so much