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The Grid That Doubles the Strength of the Ground

practical.engineering

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Re: The Grid That Doubles the Strength of the Ground

#21

Post by strken »

inigyou wrote: post #13
avesi wrote: post #7

Earlier quoted context omitted.

There appears to be a bamboo-derived plastic out there with high tensile strength, but I don't think it'd work for this application, because it degrades within 50 days of being buried in soil. I wonder if being in gravel would delay that, due to the different microbes present? It seems like there are usually biobased solutions out there, but they aren't as cost-effective or easy to procure as the forever plastics, so…

You can have material that biodegrades, or material that doesn't biodegrade. But you can't have material that doesn't biodegrade that biodegrades. Plastic is a wonder material because it's a forever material.

There's a bit of nuance here. A material which doesn't biodegrade but is inert, a material which biodegrades but only when exposed to light or moisture or heat, a material which biodegrades into something else which is in turn inert, etc.

Not really relevant to geocells but quite relevant for e.g. timber, which might last a hundred years in a roof but start to rot in six months of composting.

Re: The Grid That Doubles the Strength of the Ground

#22

Post by strken »

IncreasePosts wrote: post #15

> And these strips don’t just engage with the backfill like geogrid; they encapsulate it. I wonder when grady is going to issue a mea culpa for using too much AI in his video production?

AI has been trained on real data, and some real human speech uses the same catchy hooks as an AI.

In this case, the style seems consistent with his earlier work.

Re: The Grid That Doubles the Strength of the Ground

#26

Post by PunchyHamster »

inigyou wrote: post #13
avesi wrote: post #7

Earlier quoted context omitted.

There appears to be a bamboo-derived plastic out there with high tensile strength, but I don't think it'd work for this application, because it degrades within 50 days of being buried in soil. I wonder if being in gravel would delay that, due to the different microbes present? It seems like there are usually biobased solutions out there, but they aren't as cost-effective or easy to procure as the forever plastics, so…

You can have material that biodegrades, or material that doesn't biodegrade. But you can't have material that doesn't biodegrade that biodegrades. Plastic is a wonder material because it's a forever material.

The problem with plastic is that it often doesn't biodegrade but loses capability with time. So you end up with it turning to rubble after few decades but still polluting the environment

Re: The Grid That Doubles the Strength of the Ground

#27

Post by PunchyHamster »

40four wrote: post #6

A few of my local parks have used this technique in their parking lots. I didn’t know they were called “geo-cells” so that’s interesting. They filled them with gravel. I imagine it was a good way to save some budget versus a traditional paved parking lot

It's usually used for parking lots as a way to control vegetation. Put some geotextile at bottom layer, put grate for structure and fill it in, you end up wih flat enough, strong enough structure that doesn't need much care weed wise coz they can't get deep roots

Re: The Grid That Doubles the Strength of the Ground

#29

Post by notatoad »

lathiat wrote: post #14
Jedd wrote: post #10

I saw some examples of this while travelling in Japan last year, and am keen to replicate. I suspect, like a lot of things, the local product there is superior to what I could find back home here in AU. At some castle courtyard, we were walking around on a smooth-white-gravel surface, and I didn't immediately register how different it felt. Stare at the ground for a few moments, and notice some of the small (15-20mm)…

The sad part is how expensive it is (I’m in Australia too). Seems up front like a cheaper alternative to pavers but both the moulded plastic and the soft plastic that fans out versions are a solid $40-$45/sqm AUD. Can buy brick pavers for that and you still have to purchase the pebbles to go in it…

brick pavers need a tamped gravel base, then bedding sand, and then polymeric sand to lock them together. the cost of install is not just the cost of pavers. and installation is something that requires enough skill that it's possible to do it wrong. depending on how much weight you plan to drive over it, you might also need to pour a concrete base for them.

geogrid is orders of magnitude easier and quicker to install.

Re: The Grid That Doubles the Strength of the Ground

#30

Post by shagie »

IncreasePosts wrote: post #15

> And these strips don’t just engage with the backfill like geogrid; they encapsulate it. I wonder when grady is going to issue a mea culpa for using too much AI in his video production?

https://youtu.be/SW-NoiM726U?si=D_ehA4N8HzHYiZkf&t=142 (from 2017)

> Expansive clay isn't just an issue for buildings. All kinds of infrastructure are at risk of damage from a shifting foundation.

His production style is consistent over the past decade.

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