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  • In a few hours, this sloppy wet concrete will harden into

  • a solid, which, after a few days will be strong enough to hold many tons of weight.

  • Pasta also starts in a moist amorphous state, hardens after a few hours, and it can also hold

  • a lot of weight.

  • But there’s an important difference between capellini and concrete – noodles dry out

  • (which you can tell because when you add water, they re-absorb it and become soft again),

  • while concrete sets (you can pour as much water on it as you want, and it won’t become

  • soggy - which is good because you don’t want buildings and bridges to get soggy when

  • it rains).

  • The distinction is that when pasta is made, water simply evaporates out of the dough,

  • leaving behind a desiccated, starchy scaffolding with plenty of holes & gaps ready to re-absorb

  • water in the future and re-soften the dough.

  • When concrete sets, on the other hand, calcium oxide, silicon dioxide and other molecules

  • in the cement chemically combine with water molecules to create new compounds like calcium

  • silicate hydrate. These molecules grow into crystalline fibers that bond with each other

  • and literally cement together rock, sand, metal or whatever else you put into the mix.

  • So when concrete hardens, it’s not drying out, because water isn’t leaving it – water

  • is reacting with and becoming PART of the cement. In fact, concrete continues to set

  • for months and even years after it’s poured, increasing in strength over time and enabling

  • the construction of miraculously strong and durable structures, like the 2000 foot tall CN Tower in Toronto

  • or the 2000 year old Pantheon in Rome.

In a few hours, this sloppy wet concrete will harden into

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B2 concrete cement water soggy pasta calcium

Concrete Does Not Dry Out

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    林宜悉 posted on 2020/03/28
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