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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.
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?
I get that the US is a bit of a third world/developing nation so their ability to use clean energy is somewhat stinted, but more modern nations have made great strides towards a cleaner source of joules.
And I see this line of thinking all the time. "X is bad, because it takes a lot of energy to make X". Just clean up your energy sources, then X wouldn't be so bad.
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
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)
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!
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
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.