3 ms·

Is mine sand suitable? The sand used in cement is very specific shape and size. I think that is what makes it so difficult to produce.

by 14 3y ago

darth_avocado 3y ago
It is not. We have an unlimited amount of desert sand available to us, but we need the river sand for construction. Otherwise the likes of Saudi Arabia would be exporting sand instead of importing it for their sky scrapers. The same is true for the mining sand, only a portion of it is appropriate for construction.
- gtvwill 3y ago
  Actually that's a lie. Desert sand is fine for aggregate. https://www.sciencedirect.com/science/article/abs/pii/S2352710223020235 https://www.sciencedirect.com/science/article/abs/pii/S23527... 41.3mpa on pure desert sand is completely fine. Stronger than your houses slab your probably on now.
  - nerdponx 3y ago
    So why aren't we using it for construction?
    - gtvwill 3y ago
      Because existing organisation's would lose their profits from sand mining? Nfi there's plenty of old wives tales from before the time when you could google it and be like "oi gran your talking sh*t" that effect how we do business today. This is probably one of them?
      - nerdponx 3y ago
        > Because existing organisation's would lose their profits from sand mining? I'm willing to be cynical and conspiratorial, but this doesn't add up for me. There are so many players between "large construction firms in the USA" and "sand mafia in India" that I find it hard to believe that this is the action of a global cartel. Unless large construction firms in the USA specifically are also run by the sand mafia, which of course is possible, but would be a hell of an exposé if anyone ever caught on.
  - throw0101d 3y ago
    'Just' pressure is not the only metric; from your link: > However, the flexural and tensile strengths tended to decrease as the amount of desert sand increased, particularly beyond a 25% replacement level. So it is not a 1:1 replacement, and there are further considerations that need to be taken into account into how much (if any) desert sand can be put into a particular mix for a particular purpose. Another paper if you want to get into the weeds somewhat: > In this paper, the effect of DSRR, temperature and cooling regime on the mechanical performances of concrete produced with desert sand was analyzed. To study the influence of temperature on the microstructure of concrete produced with desert sand, the microscopic experiments (XRD, SEM) were employed. * https://ijcsm.springeropen.com/articles/10.1186/s40069-020-00402-3 https://ijcsm.springeropen.com/articles/10.1186/s40069-020-0... See also perhaps: * https://engineering.stackexchange.com/questions/18118/why-is-desert-sand-not-processed-to-make-it-suitable-for-concrete https://engineering.stackexchange.com/questions/18118/why-is... It is an area of active research, and perhaps a system will be developed to use it in a cost effective manner.
- Prickle 3y ago
  We really don't. The majority of desert is not sand. Only around 20% is sand, and around 3% consist of sand dunes. Transportation in deserts is complex due to the rocky terrain that usually fills the rest of the desert. It is economically cheaper and easier to take beach and river sand. (Especially since some countries designate sand dunes as protected areas)
Scoundreller 3y ago
Leftover sand from mineral mining might be better for concrete. As “fresh” sand it’s probably nice and jagged-y, but maybe so fresh without weathering that its weak points haven’t broken off yet.

Is mine sand suitable? The sand used in cement is very specific shape and size. I think that is what makes it so difficult to produce.

by 14 3y ago

Is mine sand suitable? The sand used in cement is very specific shape and size. I think that is what makes it so difficult to produce.

darth_avocado 3y ago

It is not. We have an unlimited amount of desert sand available to us, but we need the river sand for construction. Otherwise the likes of Saudi Arabia would be exporting sand instead of importing it for their sky scrapers. The same is true for the mining sand, only a portion of it is appropriate for construction.

gtvwill 3y ago
Actually that's a lie. Desert sand is fine for aggregate. https://www.sciencedirect.com/science/article/abs/pii/S2352710223020235 https://www.sciencedirect.com/science/article/abs/pii/S23527... 41.3mpa on pure desert sand is completely fine. Stronger than your houses slab your probably on now.
- nerdponx 3y ago
  So why aren't we using it for construction?
  - gtvwill 3y ago
    Because existing organisation's would lose their profits from sand mining? Nfi there's plenty of old wives tales from before the time when you could google it and be like "oi gran your talking sh*t" that effect how we do business today. This is probably one of them?
    - nerdponx 3y ago
      > Because existing organisation's would lose their profits from sand mining? I'm willing to be cynical and conspiratorial, but this doesn't add up for me. There are so many players between "large construction firms in the USA" and "sand mafia in India" that I find it hard to believe that this is the action of a global cartel. Unless large construction firms in the USA specifically are also run by the sand mafia, which of course is possible, but would be a hell of an exposé if anyone ever caught on.
- throw0101d 3y ago
  'Just' pressure is not the only metric; from your link: > However, the flexural and tensile strengths tended to decrease as the amount of desert sand increased, particularly beyond a 25% replacement level. So it is not a 1:1 replacement, and there are further considerations that need to be taken into account into how much (if any) desert sand can be put into a particular mix for a particular purpose. Another paper if you want to get into the weeds somewhat: > In this paper, the effect of DSRR, temperature and cooling regime on the mechanical performances of concrete produced with desert sand was analyzed. To study the influence of temperature on the microstructure of concrete produced with desert sand, the microscopic experiments (XRD, SEM) were employed. * https://ijcsm.springeropen.com/articles/10.1186/s40069-020-00402-3 https://ijcsm.springeropen.com/articles/10.1186/s40069-020-0... See also perhaps: * https://engineering.stackexchange.com/questions/18118/why-is-desert-sand-not-processed-to-make-it-suitable-for-concrete https://engineering.stackexchange.com/questions/18118/why-is... It is an area of active research, and perhaps a system will be developed to use it in a cost effective manner.
Prickle 3y ago
We really don't. The majority of desert is not sand. Only around 20% is sand, and around 3% consist of sand dunes. Transportation in deserts is complex due to the rocky terrain that usually fills the rest of the desert. It is economically cheaper and easier to take beach and river sand. (Especially since some countries designate sand dunes as protected areas)

Scoundreller 3y ago

Leftover sand from mineral mining might be better for concrete. As “fresh” sand it’s probably nice and jagged-y, but maybe so fresh without weathering that its weak points haven’t broken off yet.