Geopolymer Concrete, the perfect seasteading material

(Nick Gencarelle) #162

Just as in a regular building there is no code that states only one type has to be used. By surrounding steel with basalt you can have the best of both worlds. So use some to make your bio rock if wanted but internally use basalt.


Edited. I only intended it as a current means of comparison to steel rebar.

(.) #164

Wrong. A buoyan piece added under the water line, that is immersed in water will increase buoyancy.

Wrong, wrong , wrong. Since when are you such an authority?


Sparky, JL’s post does say:

(.) #166

Ok sorry
And twenty more characters


I don’t get it. How come we don’t see global warming on Mars or the moon for that matter if it’s related to a solar cycle. And besides the output of the Sun isn’t any higher than usual since we began measuring it


There’s next to no atmosphere on the moon, so there’s nothing to warm and we haven’t been measuring the martian climate for long enough to know. I’d imagine it does experience warming and cooling periods, just like earth.

(Larry G) #169

The information is readily available. If you have a hypothesis, test it. In this case a simple google search tells you that your assumption is incorrect:

Mars is probably experiencing some warming. It may have more to do with albedo than solar output (much like Earth’s may have more to do with deforestation than burning of hydrocarbon fuels), it may have something to do with solar cycles, and it may be measuring errors, much like Earth’s warming may be measuring errors and “adjustments” in the data.

But what does this have to do with the technical information related to building seasteads with geopolymer concrete?


I was only replying to a post about the causes of global warming which I didn’t bring up in the first place.


Funny thing, I enjoyed studying the old-school inventors, like Bell, Edison, Tesla, even the older stuff from before the I.C.E.

In theatre, I studied the telephone, in order to hook one up and make it ring properly, as well as using the line as a sound-board feed. IIRC you have something like a 24 VDC base-line, which jumps to around 48 VDC when off the hook, and the ring is another 90 VAC above the 24 VDC.


Much like “how to build a Saturn 5 rocket”, some of the best talent is now lost.


Excerpted from this pdf…


Great summary, thanks.


OPC = Ordinary Portland Cement

Good research, JL, thanks!


While I’m hopeful about geopolymers, I’m also rather wary about over-selling or minimizing the unknowns, instead of testing, testing and publishing test results.

I see a (potential, solvable) issue regarding what kinds of aggregate and reinforcing materials are long-term compatible with geopolymers. But IMHO, it can only be solved if somebody runs some real tests and publishes the results.

One issue that folks outside the concrete/structural engineering fields probably don’t know about is the problem of alkali-aggregate reaction damaging concrete. See

The alkali-aggregate reaction is a real problem that occurs slowly, when some kinds of aggregates (e.g. gravel) are (mistakenly) used in cement/concrete/whatever-you-call-it, that causes the concrete to swell and crack – sometimes leading to expensive failures. Note please that this can happen even in concrete containing no steel whatsoever!

Since geopolymers (at least the ones I’ve read about) add significant alkali chemicals to the mix, I think we need to be on guard against that extra alkali doing bad things to aggregate or other reinforcing materials.

IMHO, it’s often issues like this (uncertainties about threats to long service life) that make builders, insurers and investors want to see real-world evidence that the latest tech wizardry won’t bankrupt them.

I’m hopeful for geopolymers, but I’ve been fooled before by insufficiently-tested materials. So color me cautious.

(Larry G) #178

There’s actually quite a bit of research performed over the last 2 or 3 decades, it simply takes a bit of time to read. Some of the links above lead to significant testing.

Some things are obvious- the main problem with ferro-cement in the marine environment is the cracking you mentioned in another thread. Micro-racks allow seawater to corrode the iron elements, which causes swelling and spalling.

So the goal with geopolymer and alternative tensile elements is to get rid of the iron component, and the interactivity with the seawater that exchanges ions and weakens ordinary concrete. It’s a different chemistry than regular concrete, based on an alkali reaction, so that is not a problem.


Review on Current Geopolymer as a Coating Material



A world towards the concept of sustainable development and environment with low greenhouse gas emissions, zero waste and low energy consumption is an important endeavor. Geopolymer is an aluminosilicate materials occurred by dissolve it in highly alkaline solution then transform into tridimensional tecto-aluminosilicate materials. As an inorganic material, geopolymer has a potential in fire resistant and protective coating for different surfaces including metal and concrete due to their superior mechanical, chemical and thermal resistance properties. With an additional engineering design, in curing and sintering temperature, Si:Al ratio as well as additives used will improve the geopolymer coating properties. The present paper outlines briefly the potential of geopolymer as a coating material to bring the world towards a better future with a reduced carbon footprint.


Geopolymer Chemistry and Applications
3rd edition
Joseph Davidovits


New Generation of
Geopolymer Composite for Fire-Resistance
Tran Doan Hung1, Petr Louda2,
Dora Kroisová2, Oleg Bortnovsky3 and Nguyen Thang Xiem2


High strength geopolymers from fractionated and pulverized fly ash