I'm watching a show about the expansion of the Panama Canal. It is simply amazing the amount of concrete they are using down there. Considering things like the Hoover dam and superhighways and highrises and everything they build in China, we use A LOT of concrete. The way I understand it, concrete is what it is because of Portland Cement. Is it possible that we could use up all of the Portland Cement in the world? Is anyone monitoring this? What happens if we run out?
You have too much time on your hands.
They make it from limestone. The world has a LOT of limestone. For reference, Mt. Everest is made of limestone. So is the whole mitten part of Michigan. Lots of other stuff to.
We'll run out of a LOT of other stuff first. Silver comes to mind....
I have some really powerful little rare-earth magnets and they weren't even expensive!
I was thinking about this... a lot, actually. Like reading about all of the massive concrete structures Germany built in various places in Europe in the early 1940s. Where did all that concrete come from?
Interestingly, asphalt is getting expensive enough that I've noticed some roads being repaved with concrete again.
Rare earth metals aren't rare. Just really nasty to extract and process. Thus, China has the market cornered.
The Romans used concrete, including types that would harden underwater. The recipe for basic concrete was forgotten for a long time. Like >1K years or something. There are some theories that the pyramids are made from concrete and the blocks were poured in place.
I've been to the Panama Canal. Yep, it is truly incredible.
Portland cement's primary ingredient is Calcium Oxide, made from Limestone. Limestone is the most common material in the Earth's crust, comprising about 1/7 of the the entire crust.
There is a lot of it.
Modern concrete binder is made from Portland Cement. Roman concrete binder was gypsum and lime, with a lot of volcanic dust, which made it more resistant to salt water than modern concrete.
The Roman Pantheon is the world's largest unreinforced concrete dome.
Asphalt (bitumen) is a petroleum product, and follows petroleum pricing.
I hear the mafia uses a lot of concrete for footwear.
Look up a show on Netflix about German submarine bases. Massive undertaking.
some of those submarine pens are still too strong to be dismantled
SVreX wrote: Asphalt (bitumen) is a petroleum product, and follows petroleum pricing.
Pretty much this
You don't have too much free time on your hands pinchvalve, the right type of sand for use in concrete is getting harder to find:
http://www.nytimes.com/2014/11/05/opinion/why-sand-is-disappearing.html?_r=0
No you can't use desert sand, it's too fine and round. The UAE is importing sand because of this.
Much of the sand used in building the Panama Canal came from southern New Jersey. Not the beaches, but inland. Most of this part of the state is a thick course sand
OK, I was laboring under the mistake belief that there was a large pit in Portland OR or ME that would run dry some day. Good to know.
A bigger problem is the amount of energy required to create concrete/cement.
Sky_Render wrote: A bigger problem is the amount of energy required to *create* concrete/cement.
I don't think so...we're not going to have a shortage of energy, the only problem is where it comes from. And solar panels are getting so good and cheap that we might solve global warming by accident (although that's no reason for complacency).
Fun fact:
China has used more concrete since 2010 than the United States used in the 20th century.
Duke wrote: Fun fact: China has used more concrete since 2010 than the United States used *in the 20th century*.
Wow, that's a number that's really hard to wrap your head around. 
I find it helps to imagine it as bytes...not working this time.
makes sense.. they have what..12 times our population?
In reply to Duke: That's crazy!!
In reply to mad_machine: 4 times the U.S. population but still that's a lot of concrete.
There's a great book I'm working through called "Making the Modern World: Materials & Materialization" by Vaclav Smil. It's pretty dry in a textbook kind of way, but it's amazing in a lot of the revelations about the volume of materials used, and some of the unintended consequences of their use. The concrete section was amazing to wrap your head around, and I'm still not sure that I do completely.
Another interesting example: One of the things that was a huge consumer of aluminum was soda cans, and making the cans kept the price relatively high. So, in an effort to save money and use less aluminum, the new cans were designed... This led to the (relative) cost dropping on the cans, so now more people can afford to buy soda in cans, which led to more aluminum used overall for it.
KyAllroad wrote: In reply to mad_machine: 4 times the U.S. population but still that's a lot of concrete.
Not really, most of their economic growth in recent years is due to their massive civil works.....and before that, things like highways were hilariously under developed.
Dr. Hess wrote: Rare earth metals aren't rare. Just really nasty to extract and process. Thus, China has the market cornered. The Romans used concrete, including types that would harden underwater. The recipe for basic concrete was forgotten for a long time. Like >1K years or something. There are some theories that the pyramids are made from concrete and the blocks were poured in place.
has anyone that believes the theory about the pyramids being made of concrete ever actually been to the pyramids?
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