Geopolymer Concrete, the perfect seasteading material

(George Hawirko) #251

I losing interest here, Geopolymer has many meanings, mostly “Rabbit Holes.” Many great solutions are available but not in this thread.

(Alex Marshall) #252

I have a lot of admiration for your writing. Thank you for all your valuable input on this tconcrete


I came up with a way to make a Thermo-Plastic Basalt Glass Fiber Rebar, so instead of it just being straight, bend into place, heat to near ‘glass’ temp (like heating and bending plastic), let cool and it takes the new set, using an advanced enamel. Haven’t had the $$ to throw at making it, but the components are proven and have off-the-shelf availability.

(noboxes) #254

On adding fly ash and steel-making slag to OPC.

(noboxes) #255

It’s sad you know of the solutions, but cannot tell us.

(George Hawirko) #256

Sorry but I not sure what “You” want to know, noboxes. Should change my name to CheckBoxes:-)

(noboxes) #257

“I” would like to know of affordable alternatives to geopoly (aka “unobtainium”) and ordinary portland cement, for durability in sea water.

(George Hawirko) #258

Is this for a current project or are you just gathering specs for future reference?

(noboxes) #259

After two years of not getting any info on geopoly availability, i am currently building with steel. I can still evaluate geopoly for future use.


Commercially available Geopolymer is something like 10X the cost of concrete



Then this whole post titled “Geopolymer Concrete, the perfect seasteading material” is just plain and simple BS. At that price, 10 x the price of concrete, there is nothing “perfect” about it.

In fact, IT SUCKS.


Actually, at longevity times on the Great Pyramid scale, it could be well worth it, if the design is flexible enough.

HOWEVER, there ARE cheaper DIY formulas (some actually patented for commercial production). I just don’t have the necessary facilities to MAKE it in the quantities I’d want and would have to be commercial to afford to use it in the quantities I would want, at which point, I would no longer have the time to DO what I want.

(noboxes) #263

I am proud to bask in your eloquence. The poetry of your verbage, the pinpoint accuracy of the nouns, the way you hone in on the mental image of the material and it’s use. It’s simply stunning how you enhance this forum!

(noboxes) #264

If i remember right, @NickGri 's price and qualifications for the HPC was also out of reach.

Which i find a little interesting because Wikipedia flat out said the HPC was made by replacing (on average 50% of) portland in equal measure with the powdered slag, which was slightly cheaper.

And then to sell it, the engineering details of the customer’s use of the cement had to be turned over? That’s difficult to get right if the use is to be a protective shell, or stucco. And it’s not cost effective if one is making fish habitat.



And let me say that I couldn’t have done it without your role model! Your superb conversational skills and vast, overall seasteading related knowledge are a true inspiration to any reader of this form.

(Nick Gencarelle) #266

Our UHPC compared to any other on the market right now is easily half the price. If a product can be less than half as thick, yet still be much stronger and last for many decades compared to cements in use today how would that not be cost effective? Using our basalt reinforcements in the ultra high performance or Geo-polymers or Mag phos[hate cements means you are getting the very best, strongest and lightest possible, longest lasting solution on the planet. We are not using powdered slag either.

(Larry G) #267

Too many people want everything to be free materials, or nearly so. If it’s not nearly free, they complain about barriers to poor people.

In one sense, this is a valid criticism in the Seasteading=Freedom from oppression context. However, it is as impractical as any college dorm philosophy discussion.

I got the same reaction when I proposed that a valid path to seasteading might be conversion of “played out” commercial vessels, where the residual value was not worth commercial financing and the value proposition for commercial shipping operations was no longer there (older vessels in need of repair of upgrades, that are not competitive in today’s market primarily due to containerization of cargoes and the massive size of modern cargo container operations.) Such a vessel might cost US$300k to US$5million. You immediately hear squawking about how that is out of reach for someone on social security. I’m sorry, but that is not a solvable problem.

Such a price is still easily in reach of a small business, or a co-op, or a group of friends (or at least people who are tightly-aligned in philosophy and goals.) These kinds of prices are regularly reached by people purchasing buildings for intentional communities, non-profits, and cooperative businesses.

Note that such a vessel can’t easily compete in mainstream cargo container shipping. That constraint means nothing when you change the paradigm to something else- mobile (chemical?) processing for smaller markets, who knows?

But to bring it back to geopolymer, it’s still a very reasonable candidate for building material. If geopoly costs 10x concrete, but concrete costs 10% of steel, and geopoly lasts 10x longer than steel with 1/10th the maintenance costs, then it’s still a viable material.

Hull costs are only about 20% of the overall cost of a build anyway.


I agree up to a point…

Unlike the ‘use half as much’, the budget restraint with geopolymer is the upfront cost, which is precisely why I have tried to experiment with making it, using alternative formulas. Until I have a stable environment to be able to consistently make and test experimental batches, I cannot move forward in that area.

In a similar way, I developed and documented a solid concept for a Thermo-Plastic Basalt Rebar, using available Ropes/Twines/Rovings. I don’t have the space, equipment, or funds to start making that, either. Why bother? It solves a compound problem, when building with composite rebar. Each bend adds spring tension to the structure. WHEN something finally REALLY gives, it will be a catastrophic failure, not just a small ‘oopsie’. I don’t want that to be me…

Counting on the rebar to cost more and the Geopolymer is one thing, but, at the price quoted for Geopolymer, in a wet, ready-mix, that HAS to be used within a certain time-frame precludes significant travel and I know of 1 (ONE) company in Texas, and it is too far away, adding significant transportation expenses to the already exorbitant price of Geopolymer… and there’s STILL the question of durability…

WILL it last a minimum of 40 years? 100? 1000? Can anyone design one object, in today’s society, adaptable enough to warrant that potential extended durability? It’s not something as basic as a Hammer, but a floating home, we’re considering… I have my thoughts on how to build in the ability to retrofit upgrades and intend to apply that to anything I build, even when I rebuild the RV I have. What else will have to be adapted, down the line? How do you plan for the replacement of obsolescent seals. deteriorated insulation, even repair damages and replace equipment, when you do not know a fairly precise length of service? How do you plan around the changing mentality of people? Say I build it and it’s expected to last 150 years before major tear-down and restoration… Is it worth my great-great-great grandson’s effort? Will it even BE in the family anymore?.., but I DO plan for that eventuality and hope the materials availability is up to the challenge.

(Larry G) #269

Most prematurely obsolescent shipping is due to efficiencies of container cargo scale, not due to being unfixable, in bad repair, or not operable in some way. (Although it’s entirely possible to squander the standard ~30 viable years of commercial service for regular steel vessels through lack of regular maintenance)

Consider that homes built 100 years ago are not obsolete. In many cases they have been torn down because they weren’t in good repair, and in some cases, homes in usable condition have been torn down to build more desirable ones, but this is usually driven by change in demographic wanting larger, fancier, homes, not necessarily because the originals weren’t usable. In some cases, modern appliances and heating solutions make the basic design less user friendly.

Consider that Europe has a large number of structures that have been continually occupied for literally hundreds of years.

The challenge is in the following aspects:
-Saltwater environment

If you can design something that has continuing operations and repair in mind, of a material that resists time and the environment well, that is still safe and comfortable in 100 years, people will still want to occupy it in 100 years.


Seaweed in Geopolymer…


Beginning @ 35:33

2nd portion begins at 44:32