Geometry optimization for compressed earth block shells

[gm1 (Guillaume)]

Dear all,

I have to evaluate the feasibility of a structure in compressed earth bricks somehow like this; base diameter about 3m and 4 to 8m tall. This might be realized in Geneva in June. As we should be able to enter it, it must be structurally safe. For now we are considering working with bricks made by http://www.terrabloc.ch/, a swiss manufacturer of compressed earth bricks.

I saw this project on-line, kind of similar although not the same material.

Fireplace for Children | Haugen/Zohar Arkitekter - Arch2O.com

Do you have any idea of how to optimize the geometry in order to avoid structural buckling? Could this be made with Karamba or RhinoVault? Any idea, example or reference would be more than welcome.

[Joseph_Oster]

Can you please supply the shape and brick sizes?

Control gap between bricks in a wall grasshopper

You didn’t post a model so I can’t speak to your particulars. I took a copy of the model referred to above and added a cyan group that offers a “Gradient” option affecting the gap. The output of the Range component can be reversed so the gap diminishes toward the top instead of the bottom. I replaced a pair of Split Tree components with a better way to cull bricks on alternate rows. There are some assumptions made here that I’d rather not get into changing, though I can see reasons to do so.…

Brick Wall, Bricks intersection

[Joseph_Oster]

[gm1 (Guillaume)]

Hi Joseph, thank you so much for letting me know about this other topic. I just tried your definition and it works very well on that “chimney” geometry.

One interesting development I would try would be to vary the gaps with attractor points. Might be interesting for light and/or wind catching…

Regarding the structural stability of the overall geometry built in bricks, do you have any idea how I could evaluate it?

[Joseph_Oster]

I look forward to seeing how you do it.

[karamba3d]

Hello @gm1,
in Karamba3D you could calculate the structure as a shell with an orthotropic material. In the current WIP version of Karamba3D (see www.karamba3d.com/nightly-builds) it is possible to define materials with different strength values in tension and compression and different yield criteria.
One could either use the cross section optimizer to look for the minimum wall thickness or use a uniform wall thickness and optimize the geometry towards a given maximum value of utilization.
Best,
Clemens

[old_taz]

Perhaps Scan & Solve?

Scan-and-Solve for Rhino

[gm1 (Guillaume)]

Dear @karamba3d / Clemens,
Thank you very much for your kind reply. Your second option “uniform wall thickness and optimization” seems to be the perfect way to reach my goal. Any advice on a tutorial I could follow to get acquainted with Karamba in that specific field (shell optimization)?
best,
Guillaume

[karamba3d]

Dear @gm1,
you could have a look at the manual regarding cross section optimization for shells.
One possible approach would be to take the control points of your surface and change them using e.g. Galapagos so that under given loads a sucture with minimum mass results.
– Clemens