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A comment on The U.S. economy is growing and using less and less stuff to do so. Parent comment

Re:The U.S. economy is growing and using less and less stuff... by thedudeabides5 on Friday September 20, 2019 @01:20AM (#21023508)
Re concrete, I’ve been hearing a lot that we are running out of sand (the kind we make glass out of and the kind we make concrete out of).

Is that true? Anyone have numbers/research on sand that’s good?

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Re:The U.S. economy is growing and using less and less stuff... by mdorazio on Friday September 20, 2019 @01:50AM (#21023633)
Depends who you mean by "we". Seems there are regional shortages [1], but the US only hits supply constraints occasionally.

[1] https://www.smithsonianmag.com/science-nature/world-facing-g...

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Re:The U.S. economy is growing and using less and less stuff... by rapnie on Friday September 20, 2019 @04:54AM (#21024553)
Also discussed on HN:

https://news.ycombinator.com/item?id=15739917

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Re:The U.S. economy is growing and using less and less stuff... by imtringued on Friday September 20, 2019 @05:19AM (#21024719)
There is an abundance of sand away from the construction sites but transportation is too expensive so regional suppliers are preferred.
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Re:The U.S. economy is growing and using less and less stuff... by logfromblammo on Friday September 20, 2019 @10:52AM (#21027329)
Though it seems like it might be easier to ship sand for pre-stressed concrete crossties, given that all the materials must necessarily be connected to the rail network.

Also, I wonder why concrete crossties don't use neoprene bearing pads under the rails to reduce the abrasion problem.

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Re:The U.S. economy is growing and using less and less stuff... by simonrobb on Friday September 20, 2019 @11:26AM (#21027737)
Are concrete crossties pre-stressed? It makes sense now I think about it, but I'm just surprised more effort than "pour concrete into a mold" goes into such an unassuming structural member.
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Re:The U.S. economy is growing and using less and less stuff... by logfromblammo on Friday September 20, 2019 @04:20PM (#21030834)
I'd guess that poured concrete is not cost-competitive with timber crossties, and pre-stressing is the only way to make them cheaply enough to compete.
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