On Geofoam
theprepared.org
theprepared.org
Potential toxicity of polystyrene microplastic particles https://www.nature.com/articles/s41598-020-64464-9
"Polystyrene is ubiquitous within sea-surface samples collected from across the globe" https://pubs.acs.org/doi/10.1021/es504525u
Am I missing something?
Also, concrete degrades by itself. In decades it crumbles, pulverizes and goes back into being soil.
But, importantly, it does not become toxic particulate like plastic.
[edit: corrected phrasing, thanks zdragnar]
Same for other sustainable materials like compacted soil, gravel, sand...
Biodegradable would seem to imply to me that bacteria and fungi feast on it and convert it to what we consider soil.
* which is an absolute menace in my opinion
Edit: s/expanded polystyrene/styrofoam
Despite its uncanny appearance, geofoam is incredibly prosaic. Essentially, it’s polystyrene. Expanded polystyrene (EPS) geofoam — the most common type — is made from small polystyrene resin beads that contain microscopic cells filled with a blowing agent, which expand when exposed to steam under controlled pressure and are molded and fused into a brick shape.
So it degrades, but causes pollution, therefore it is not biodegradable. That is my understanding.
It appears that people are paying attention to the ecological impact. (In some places, at least.)
If the foam blocks are buried, it's less likely they'll make it into the water cycle. (That's not to say they won't cause other problems.)
Also, all the samples collected are not biodegraded, but rather the actual molecule of plastics that's simply gotten smaller and smaller. See "microplastics":
These blocks will eventually need to be disposed of, or they will become rubble which will "naturally" decay - and by decay I mean gradually have bits eroded off and scattered into the wind/water.
Once they cease to be solid blocks, they become virtually impossible to clean/dispose.
Anyone looking over my comment history knows that I am nobody's fool for overblown environmental crises. But just look at that video of them piling up the blocks. Those little clingy granules are going everywhere already, and that's before anybody tries to chop up some infrastructure they've built with this.
What a waste.
It looks more like a national security issue. If we're ever at war then the enemy can always tip over a jug of petroleum ether to turn our deeply embedded geofoam foundations into glue, which I imagine would cause everything built on top to crumble too. It would appear they're mostly building highways using this stuff (rather than skyscrapers) so that shouldn't be too much of a vulnerability but it probably isn't what Dwight Eisenhower had in mind when he built the interstates.
[1] Aabøe R, Frydenlund TE (2011) 40 years of experience with the use of EPS geofoam blocks in road construction. Paper presented at the 4th international conference on geofoam blocks in construction applications, Lillestrøm, Norway, 6-8 June 2011
What is a "long time"? Is it one human lifetime? The time period in which these blocks will be a blight is a whole lot longer than the time period where they make a nice landscape, it's just that the nice landscape part comes first. Should we do anything we want assuming that what happens after we're dead is irrelevant?
One wreck involving a fuel tanker without sufficient containment and the entire subgrade starts to dissolve and buckle and sink?
I guess they forgot about all the machinery and oil consumed by the manufacturing process. Granted, the oil is not being burned but polystyrene is not really environmentally friendly itself either: https://en.wikipedia.org/wiki/Polystyrene
I see the economic and engineering qualities, especially when building whimsical parks and so on (which is a frivolous use case). But I can't help but feel this is a perverse way to build natural landscapes such as parks. Imagine what happens when a burrowing animal finds its way onto one of these things? What happens when you have to dig under the foam in the event you need to do so? What about tree roots? What about micro-plastics? et cetera.
This line sums it up nicely:
> It can come as a shock to realize that giant bricks of polystyrene are stuffed below the turf, like silicone implants under the skin of a city.
Perfect for the Instagram generation: a fake city with fake tits.
Make sure the foam used has the proper PSI rating, and make sure you have proper drainage to reduce hydrostatic pressure, and there's no reason these things can't last 'forever'. It's not like the foam is biodegradable after all.
I struggle to understand this. Do people who hold this point of view wish we got rid of cars and instead manually carried materials everywhere? Should we ditch earthmoving equipment in favor of shovels? After all, that would employ more people for longer.
This is an instance of the "broken window fallacy". To understand the nature of this fallacy, I highly recommend Economics in One Lesson by Henry Hazlitt [0]. It's short and easy to read.
However, Hazlitt's lesson is not the complete story. The question that Hazlitt does not answer is, what is "the long run", and how exactly do the gains from productivity get distributed to "everyone"? This is likely where a lot of leftists would object to Hazlitt, arguing that it's better to protect current jobs than to let capitalists (or whoever) suck up all the gains for themselves and never redistribute them. You can argue about the semantics of whether it's possible to "hoard" wealth, but ultimately there is some merit to that argument. But the fallacy remains the fallacy, even if wealth redistribution is an unsolved problem.
[0]: http://leeconomics.com/Literature/Henry%20Hazlitt%20Economic...
https://www.the-scientist.com/news-opinion/beetle-larvae-can...
But the alternative to geofoam is usually clean fill, like sand, which weighs about 110 lb/cf. contractors ask to substitute it because it’s cheaper, but it almost always results in thicker structure and more rebar to support it.
Why not aircrete?
I read up on it when we did electronics for concrete mixers.
The chemistry of foam concrete is a very inexact science, bordering on being "possible to get right through talent only"
Very little literature on it, and proprietary foaming agents all come from Eastern Europe with zero info, or instructions beyond "mix this stuff with water 100:1, and pray"
We are, in fact, trying to convince the owner to let us put in geofoam in place of the specified aircrete.
It's much, much easier to bring in a trailer of geofoam blocks, place and size them then compared to pouring a lift of concrete and ensuring proper aeration, vibration, temperatures, etc.
https://tarmac.com/products/blocks/aircrete-blocks/#all?pl1_...
And have you ever had packing material that over time had more and more corners rubbed/ripped off, leaving little foam balls stuck to every nearby surface? Now imagine that orders of magnitude larger scale. I hope you _really_ like little foam stuck to everything.
In the end, railroaders like XPS foam as opposed to EPS foam due to lack of "beads" and mess.
"Oh, I certainly hope no terrorists come, and pump oil directly under our facilities!"
"Yes, that would truly be a devastating blow!"
"We can only hope that no hostile actors from oil-rich nations learn about our critical vulnerability to this clever, effective tactic!"
How does biodegrading release carbon?
This is misleading. Trees in a forest store carbon as long as the forest exists. Individual trees might degrade (or be trapped underground), but new ones are born.
The biggest plus it doesn't turn into a chemical weapon if there is fire, and it can be poured right on site.
I almost spit out my coffee when I saw the section on levees and the anchors "(if necessary)" annotation. I would be very reluctant to market an extremely low-density product as a barrier for flood protection applications. It really makes me wonder about the rest of the statements in the brochure.
For levees, there’s also the even lighter https://en.wikipedia.org/wiki/Inflatable_rubber_dam (but those do have to be grounded)
My reaction is that "if necessary" isn't really an "if". It is necessary, or your levee may float off precisely at the time you need it to work.
So instead of using some of the millions of tons of existing styrofoam waste as landfill they produce brand new styrofoam and put that in there instead? Did I get that right?
I don't know if I would use this stuff outdoors, though. We had a bean bag chair full of polystyrene balls leak outside, and I was finding the stuff in my yard for years.
Rammed earth and other more integrative materials should be more popular, imo. Having crap like this geofoam should be considered completely unacceptable, like using baby blood to mix cement.