3d printing record tall turbines

[Jay McKinsey + 1,489]

GE Renewable Energy, COBOD, and LafargeHolcim have announced a three-way partnership to co-develop 3D printed, “record-tall” wind turbine towers. LeveragingCOBOD’s concrete printing technology with LafargeHolcim’s leading construction materials, GE will be able to tie the multi-year project together with itsextensive resources. The trio intends to boost global renewable energy production while lowering the levelized cost of energy.

The next steps are to produce a “production-ready printer”, a comprehensive range of materials to scale up production, and finally a full wind turbine prototype with a 3D printed base. To achieve this, GE will offer design, manufacturing, and commercialization expertise; COBOD will focus its efforts on optimizing the 3D printing technology; and LafargeHolcim will formulate the concrete, taking charge of its processing and application.

https://3dprintingindustry.com/news/ge-cobod-and-lafargeholcim-set-to-3d-print-record-tall-wind-turbines-172702/

[Dan Clemmensen + 1,011]

It seems to be the base, not the actual tower, but the article makes it quite hard to be sure.

The other "interesting" point: making Portland cement emits about 8 percent of all anthropogenic fossil CO2. Half of that is in the fossil fuel used to heat the stuff, but the other half is fundamental, because converting lime to quicklime releases CO2. This is not unique to wind tower bases, of course. Concrete is used in lots of places in the energy industry.

Edited June 20, 2020 by Dan Clemmensen
missing percentage

[Refman + 207]

http://www.digitaljournal.com/tech-and-science/technology/taller-wind-turbine-bases-using-concrete-3-d-printing-technology/article/573421

 

[footeab@yahoo.com + 2,131]

Unless they make a machine that autolays in rebar, welds the rebar, perfectly ties in the base bolts, smooths the surface, seals the surface, wets the surface for 24 hours, this is beyond stupid. May as well 3d print it out of stainless steel.  Insanely expensive, but hey, while we are dreaming... At least SS can take tensile loads.....🙄

[Dan Clemmensen + 1,011]

8 hours ago, footeab@yahoo.com said:

Unless they make a machine that autolays in rebar, welds the rebar, perfectly ties in the base bolts, smooths the surface, seals the surface, wets the surface for 24 hours, this is beyond stupid. May as well 3d print it out of stainless steel.  Insanely expensive, but hey, while we are dreaming... At least SS can take tensile loads.....🙄

There is now an entire industry devoted to 3D printed concrete, and They have not ignored reinforcement. The big "printer" is just a highly automated concrete pump. It does not pretend to do the whole job. Here's an article:

https://3dprint.com/221642/study-reinforcing-concrete/

 

[Enthalpic + 1,496]

8 hours ago, footeab@yahoo.com said:

Unless they make a machine that autolays in rebar, welds the rebar, perfectly ties in the base bolts, smooths the surface, seals the surface, wets the surface for 24 hours, this is beyond stupid. May as well 3d print it out of stainless steel.  Insanely expensive, but hey, while we are dreaming... At least SS can take tensile loads.....🙄

I could imagine a system where the print head / nozzle also feeds some wire that ties into the lower layer like a chain link fence.  Alternatively, use a chopped fibre in the mix.

Another option is to run a large cable down the centre and compress the entire structure (like the CN tower).

[footeab@yahoo.com + 2,131]

4 hours ago, Enthalpic said:

I could imagine a system where the print head / nozzle also feeds some wire that ties into the lower layer like a chain link fence.  Alternatively, use a chopped fibre in the mix.

Another option is to run a large cable down the centre and compress the entire structure (like the CN tower).

To get tensile, you can't use fibers and pump it.  Fibers have to be to high of a %%%.  Done several concrete slabs and my options were low %%% in the slurry but maybe putting in more by hand when finishing.  It plugs the pump/hose.  Fiber as a pumped solution is out.  Possible to add as "printed"... mix in place?  No.  Why?  Has to attach to lower layer and a layered cake mix does not work even if in a slurry.  Nothing ties in vertically. 

Weaving, could maybe work.  Could possibly weave/weld, but here we have a MASSIVE problem, for a structure such as this, it would require 3cm rebar...  Good Luck "weaving" that.  Why such giant rebar?  Besides the obvious normal cracks, you MUST have giant bolts welded to said rebar poking out the top to attach to base of steel normal tube turbine tower.  Now could it be possible to make a "cap" male/female tower attachment without bolts... onto concrete... Uh, I suppose everything is possible.  Hate to think what thermal expansion would do to that joint overtime let alone load variation.  Turning your concrete tower into dust does not seem a good option either.  It is all about load distribution.  Note: I brought up the cap idea so you could do the giant compression cable possibility and maybe get away with no rebar and only low percentage fiber to stop initial cracking.  Still have the sealing problem, but at least that is possible to fix and there are solutions.  Expensive solutions, but solutions none the less.