Why is the hoover dam so thick if the center won’t cure for 125 years?
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The amount of material used is based on how much strength is required – not how long it will cure. Concrete will reach more than 70% strength after 7 days of curing (typical).
Unless you think “not cure = 0 strength” which is mistaken.
If you made the wall thin – even if it cures quicker, it will fail. When doing engineering, always keep in mind the overall goal.
The concrete cured long ago. Curing is the process where the cement reacts with water, all meaningful parts of this reaction happen within a few weeks of the concrete being poured.
The chemical reactions generate a lot of heat, and when you’re pouring something that big the heat could take a long time to dissipate **if it were poured all at once**.
The dam wasn’t poured in one go, it was poured in a large number of smaller pours, with water filled pipes used for active cooling to help dissipate the heat faster. For the meaningful portions of the curing, the heat was dissipated long ago.
As to why it was poured that thick – that’s how big the engineering needed it to be to safely and reliably hold back that much water across a span that big. If they could have used less they would have.
Because that’s how thick it needed to be to have the strength to withstand the pressure of the water behind it. We build things based on how strong they need to be, not based on how fast the concrete cures.
“The Hoover Dam concrete would cure in 125 years by conventional or natural methods. Crews, however, used some innovative engineering methods to hasten the process.”
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Can someone ELI5 the question cause I have no fucken idea what they asked?
Why wouldn’t it cure? As far as I understand modern concrete doesn’t require contact to air or the water to evaporate.
It’s more likely got to do with making the dam heavy enough so that it doesn’t topple under the force of the water behind it. Concrete is heavier, more consistent and easier to place than soil, so civil engineers often specify concrete when something heavy is needed to weigh down a structure and keep it in place.
In that context, it’s not always about achieving the maximum strength of concrete. For example, they could’ve designed the dam taking into account the concrete at the centre would only achieve a limited strength. Anything beyond that is extra. The weight however, it’ll weigh as much whether its fully cured or not.
The dam is so thick because the sheer weight of it is what’s holding it down on bedrock and the force of the water in Lake Meade is pushing the edges of its arch shape into the walls of the canyon. It’s not attached in any way to the bedrock or the canyon walls.
When it was constructed there was a massive network of cooling pipes built into the dam to control the cure rate. This was to regulate the temperature so the utter mass of it wouldn’t heat up too quickly and cause problems with the curing process (think microwaved hot pocket: cold on the outside, liquid hot magma in the center)
Bro really? Because it’s super thick, at an almost impossible level. If you pour a 48 inch patio foundation at you home, it takes 3-5 weeks to cure snd another 10+ to “dry” now multiple that by one of the biggest dams in the world
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