Heidelberg Inaugurates 3D Printed Data Center
cobod.com
cobod.com
They seem to have issues with rain (no real surprise), but the process seems relatively straight forward.
I wonder if, for smaller scales, a cable-driven, flying delta could be used? For garage-sized buildings or smaller houses this could work (though I believe pre-fab to be cheaper).
How will it look in 5 years when green stuff starts to grow in those horizontal grooves?
That's a great idea. Why wait 5 years instead of seeding it with vegetation now, even algae?
It will be greener, as not only in colour, but also absorbing more CO2. The concrete itself absorbs CO2 as it hardens. Also if they plant some treens around it and it's virtually part of the landscape. I really like the low visual aspect and the organic, non aggresive shapes. It's also not overly organic.
The other way is to print supports and knock them out post construction. But the issue of overhangs is a serious one for 3d printed structures.
I'll skip the layer-height comments but the thought did make me giggle.
Building-grade 3D printers work by moving a giant and heavy nozzle across a wobbly giant frame, set on whatever uneven ground that happens to be at the building site. Said nozzle extrudes a concrete mix that can only be transported to the nozzle in liquid form, and one must wait for the layers to solidify before the next one can be laid down. Also, said concrete must not be liquid enough, that it flows off the print surface (like regular concrete), but must be liquid enough to be pumped around the machine. Clearing clogs must be a nightmare. Also, concrete sucks in tension, which is why steel bars are inserted into it, to pre tension it, which is not possible with this technology.
For all the engineering reasons desktop 3D printers make sense, building grade ones don't.
https://hackaday.com/2014/09/01/update-3d-printed-concrete-c...
And as someone who has 3d printed stuff, there is a distinct lack of (hard to print) overhangs in this structure.
By the way, imo one of the hallmarks of impractical technology is stagnation, dude did it a decade ago, and 3d printed structures have the same problems today.
no, they don't have the same problems today.
Building houses on planar lines with concrete extrusion doesn't represent the cutting edge, it represents the technology that has been vetted and approved enough for public ownership and land endorsement.
multi-axis extruders with large DoF and non-planar routing is approaching the state of the art, and overhangs are well dealt with.
3d printing in general is one of the least stagnant industries I can think of right now. It's being adopted en masse by the largest groups and is generally receiving a lot of intellectual attention.
I still don't see how you can build tensioned reinforced concrete structures with this tech, and overhang bridging is not possible due to fundamentally different material properties than say, PLA.
To be clear I'm not saying the technology doesn't work, just that it's not better than anything we have now, because of the problems I outlined, and thus is relegated to niches.
There's one overhang solution in my previous link, the more recent videos about printed houses with windows use a different, traditional, solution: lintels.
As for reinforcement, I can't say I really deeply understand the Wikipedia page "Reinforcement in concrete 3D printing", but it is quite sizeable and lists many things:
https://en.wikipedia.org/wiki/Reinforcement_in_concrete_3D_p...
To be clear, I also think 3D printed concrete is a case of throwing buzzwords at problems rather than a good idea, but not because it doesn't work, rather because it produces a merely OK result for what is the single cheapest part of the construction process — I can get a prefab shell of a house built here in Germany for €100k, but that turns into €550k when you add the land, preparation of the land, connecting utilities, wiring and plumbing, and interior plastering.
I never claimed that it was impossible, but that there are fundamental differences which makes squirting out thermoplastic out of a small nozzle quite convenient, and concrete out of a huge one, quite problematic.
The thing you wrote about lintels, and some of the stuff I've seen about reinforcement with rebars on the link you provided, which all need to be done manually make the process labor intensive, the issue 3D printed building were designed to solve in the first place.
I'm honestly puzzled by some of the techniques, where one guy is spraying shotcrete at a rebar structure - what is being 3D printed at this point?
And the resulting building will be a concrete house - not necessarily the most environmentally conscious, beautiful, energy efficient, best insulating material.