> 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
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.
"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
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.
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.
> 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?