5 ms·

https://www.frontiersin.org/articles/10.3389/fmars.2021.768470/full https://www.frontiersin.org/articles/10.3389/fmars.2021.7684... > Studies carried out by th

https://www.frontiersin.org/articles/10.3389/fmars.2021.768470/full https://www.frontiersin.org/articles/10.3389/fmars.2021.7684... > Studies carried out by the Secretariat of Ecology and Environment of Quintana Roo state, Mexico, found that the resistance of the bricks is 75–120 kgf/cm2 That's far below concrete, isn't it?

frandroid 3y ago
Yeah I'm thinking, one 5-point earthquake and this falls apart? I mean it's better than mud bricks, but...
- hgomersall 3y ago
  I'm not an expert, but I'd be surprised if concrete is at all earthquake resistant without rebar.
  - dghughes 3y ago
    Ancient Romans didn't use rebar in their concrete but they did use aggregate of different densities depending on what section of the building would be under stress. Plus if cracks form their concrete self heals due to the compounds used in it.
    - mrguyorama 3y ago
      How many earthquakes did ancient rome suffer?
      - Mtinie 3y ago
        Quite a few through the centuries, with the moderate to large quakes originated from the Apennine mountains’ Mount Vettore fault about 80KM away from the city. https://www.researchgate.net/publication/236950808_Beyond_the_damage_threshold_The_historic_earthquakes_of_Rome https://www.researchgate.net/publication/236950808_Beyond_th... https://blogs.agu.org/geospace/2019/03/04/seemingly-dormant-geologic-fault-damaged-famous-roman-buildings-1500-years-ago/ https://blogs.agu.org/geospace/2019/03/04/seemingly-dormant-...
- toast0 3y ago
  You should be able to reinforce this while building, just like with other masonry. Additionaly, if the structures are fairly small, and the walls are properly tied together, that may be enough.
- culi 3y ago
  Concrete isn't known for being very earthquake resistant. If you're building for that wood is a much better choice
abathur 3y ago
The primary link doesn't explain the other 60% of the formulation, but IIRC (from watching the video linked in my top-level comment) the other component is waste dirt from construction projects. I'd expect it to be less strong than concrete, so I guess more fair comparisons might be mud bricks, other mud-brick + X formulations, and traditional clay bricks? edit: but worth noting that the paper you linked does mention that someone else is making "sargacreto" that is 40% sargassum and 60% concrete, though it says there aren't numbers to cite for its strength yet.
ajmurmann 3y ago
Wouldn't the proper comparison be other bricks?
karaterobot 3y ago
Yep, and well below titanium as well. So, if you've got a beach where a bunch of titanium washes up every year, my advice is to use that instead.
- benj111 3y ago
  whats the compressive strength of sand? could just use that.
terminous 3y ago
- First-class brick has a compressive strength of 105 kg/cm². - The compressive strength of a second-rate brick is 70 kg/cm². - Common building bricks have a compressive strength of 35 kg/cm² - The compressive strength of sun-dried brick is between 15 and 25 kg/cm². Source: https://housing.com/news/compressive-strength-of-bricks-meaning-assessment-and-how-to-test/ https://housing.com/news/compressive-strength-of-bricks-mean...
culi 3y ago
"Concrete" is a composite material that can vary wildly depending on composition and process. These tests on grade M10 concrete for example concluded with 136, 131, and 147 kg/cm2 for their 3 samples. For plain cement, generally grade M15 is used[1] which is about 153 kg/cm2 [0] https://civilplanets.com/compressive-strength-of-concrete/ https://civilplanets.com/compressive-strength-of-concrete/ [1] https://theconstructor.org/concrete/grades-concrete-strength-selection/20570/ https://theconstructor.org/concrete/grades-concrete-strength...

frandroid 3y ago

Yeah I'm thinking, one 5-point earthquake and this falls apart? I mean it's better than mud bricks, but...

hgomersall 3y ago
I'm not an expert, but I'd be surprised if concrete is at all earthquake resistant without rebar.
- dghughes 3y ago
  Ancient Romans didn't use rebar in their concrete but they did use aggregate of different densities depending on what section of the building would be under stress. Plus if cracks form their concrete self heals due to the compounds used in it.
  - mrguyorama 3y ago
    How many earthquakes did ancient rome suffer?
    - Mtinie 3y ago
      Quite a few through the centuries, with the moderate to large quakes originated from the Apennine mountains’ Mount Vettore fault about 80KM away from the city. https://www.researchgate.net/publication/236950808_Beyond_the_damage_threshold_The_historic_earthquakes_of_Rome https://www.researchgate.net/publication/236950808_Beyond_th... https://blogs.agu.org/geospace/2019/03/04/seemingly-dormant-geologic-fault-damaged-famous-roman-buildings-1500-years-ago/ https://blogs.agu.org/geospace/2019/03/04/seemingly-dormant-...
toast0 3y ago
You should be able to reinforce this while building, just like with other masonry. Additionaly, if the structures are fairly small, and the walls are properly tied together, that may be enough.
culi 3y ago
Concrete isn't known for being very earthquake resistant. If you're building for that wood is a much better choice

abathur 3y ago

The primary link doesn't explain the other 60% of the formulation, but IIRC (from watching the video linked in my top-level comment) the other component is waste dirt from construction projects. I'd expect it to be less strong than concrete, so I guess more fair comparisons might be mud bricks, other mud-brick + X formulations, and traditional clay bricks? edit: but worth noting that the paper you linked does mention that someone else is making "sargacreto" that is 40% sargassum and 60% concrete, though it says there aren't numbers to cite for its strength yet.

ajmurmann 3y ago

Wouldn't the proper comparison be other bricks?

karaterobot 3y ago

Yep, and well below titanium as well. So, if you've got a beach where a bunch of titanium washes up every year, my advice is to use that instead.

benj111 3y ago
whats the compressive strength of sand? could just use that.

terminous 3y ago

- First-class brick has a compressive strength of 105 kg/cm². - The compressive strength of a second-rate brick is 70 kg/cm². - Common building bricks have a compressive strength of 35 kg/cm² - The compressive strength of sun-dried brick is between 15 and 25 kg/cm². Source: https://housing.com/news/compressive-strength-of-bricks-meaning-assessment-and-how-to-test/ https://housing.com/news/compressive-strength-of-bricks-mean...

culi 3y ago

"Concrete" is a composite material that can vary wildly depending on composition and process. These tests on grade M10 concrete for example concluded with 136, 131, and 147 kg/cm2 for their 3 samples. For plain cement, generally grade M15 is used[1] which is about 153 kg/cm2 [0] https://civilplanets.com/compressive-strength-of-concrete/ https://civilplanets.com/compressive-strength-of-concrete/ [1] https://theconstructor.org/concrete/grades-concrete-strength-selection/20570/ https://theconstructor.org/concrete/grades-concrete-strength...