Is the world really running out of sand?

Post by pfdietz » Wed, Oct 02, 2024, 7:43 PM UTC

lazide wrote: post #203

WillAdams wrote: post #189

Earlier quoted context omitted.

For some places that is happening: https://www.smithsonianmag.com/sponsored/more-than-98-percen... 2020 had the UK reaching 43%: https://www.nationalgrid.com/stories/energy-explained/how-mu... Interesting point about electric being only a small part of overall usage --- I guess direct heating and things such as smelting/refining metals makes up the bulk of energy usage?

If we’re being honest, I think we should probably also include raw chemicals that would otherwise be used for things like direct heating. So for example, crude oil used for making asphalt, plastic, etc. or natural gas used for fertilizer. Since replacing them would consume energy too. That is a less obvious piece of math, but if we’re talking carbon neutral it would matter doesn’t it?

Post by mlsu » Wed, Oct 02, 2024, 11:17 PM UTC

dyauspitr wrote: post #202

kilna wrote: post #171

Earlier quoted context omitted.

He explained it in the video. The amount of water was adjusted so the viscosity (well, workability) was identical between the samples in the second test. Less water in concrete has a huge positive influence on strength, and rough sand needs more water to be workable. Thus, for comparably workable samples, rounded sand concrete with less water was actually stronger.

But given the right amount of water, which one has the higher absolute strength?

Post by canadianfella » Thu, Oct 03, 2024, 6:51 PM UTC

junon wrote: post #164

whartung wrote: post #122

Earlier quoted context omitted.

Just marveling as an old school computer programming geek that I happen to be in a forum that also includes someone in the tugboat business.

We have the programmer to woodworker pipeline, programmer to runner pipeline... is there a programmer to tugboat operator pipeline I'm missing out on?

Post by dyauspitr » Fri, Oct 04, 2024, 2:21 PM UTC

mrguyorama wrote: post #205

dyauspitr wrote: post #202

Earlier quoted context omitted.

But given the right amount of water, which one has the higher absolute strength?

Define "right" amount of water. There is no singular correct amount of water in a concrete mix. It is dependent on the properties you want, the materials you have available, how things are going that day, etc.