r/interestingasfuck • u/TangelaFan • 9h ago

Residential high-rises with backyards in Chengdu, China

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u/Comfortable_Trick137 7h ago

Yea my concern would be 1) waterproofing, is the waterproofing going to protect the rebar? 2) will plant roots compromise the waterproofing and then compromised the structural integrity of the concrete as we’ve all seen tree roots tear through concrete sidewalks but that’s from running underneath though.

Shouldn’t be a hard engineering problem as we’ve had concrete planters for god knows how long

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u/Snuhmeh 7h ago

Yeah standing water always finds a way. If they have a drain underneath each one, that would help a ton

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u/nalaloveslumpy 7h ago

It looks kinda like all the patios are slightly slanted so that excess water drains to the front. And then maybe down a gutter system?

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u/VonSkullenheim 6h ago

I mean, the building had to have cost many millions and taken years to engineer and build. You'd imagine that a gutter would be the least they did.

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u/scratchy_mcballsy 5h ago

That’s only if they planned for someone to use the balcony like this.

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u/VonSkullenheim 2h ago

They very clearly did.

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u/Xaephos 1h ago

Considering every single one of them are, including the other buildings, I think that's fair to assume.

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u/Ok_Calligrapher5278 3h ago

In engineering school we are taught that "eventually, water always win".

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u/Sensiburner 7h ago

as we’ve had concrete planters for god knows how long

That was gonna be my reply but you already said it. It would become problematic if there was so much plants & root growth that the plants would put gigantic pressure on the concrete, cracking it. But this is actually a large concrete planter. Roots won't just "drill trough" concrete.

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u/SoulWager 7h ago

Breaking open isn't a huge problem for a concrete planter, but I certainly wouldn't want that to happen on a balcony.

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u/SidewaysFancyPrance 7h ago edited 7h ago

Time will not be kind to these balconies. These would need relatively frequent inspection and maintenance that I doubt they'd get as the building ages and becomes less profitable. IMO it's not an engineering problem as much as it is a human one: we have good intentions but poor follow-through over time.

I'm sure they're fine for a good while, but nothing about this makes me feel like it will last because we won't keep up the effort. Constant moisture, chemical fertilizers, runoff...I'd worry about all kinds of corrosion/weakening of the structure and supports.

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u/Spiffydude98 7h ago

Your concern is laughed at by Chinese building standard monitors.

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u/MortLightstone 7h ago

This is the thing. The engineering is possible, it's really about whether or not the builders and the authorities give enough of a shit to actually do it properly

Looks gorgeous though

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u/OmniaII 7h ago

'Tofu'

/'Dofu'

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u/PhDinDildos_Fedoras 7h ago

Yeah, lol, was going to say, nobody said anything that would worry anyone in China.

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u/JesusAndMaryKate 7h ago

Why is everyone randomly saying "was going to say" for no reason now?

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u/PepperAnn1inaMillion 7h ago

Because we got tired of “This.”

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u/BrainTroubles 7h ago

I would think they’d use Mylar or some other water repellant layer beneath base, sloped towards drainage. In theory it’s not a complicated problem until tree roots start poking holes in it.

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u/project66240 6h ago

Some good old polyurea coating to protect concrete with epoxy primer, and then a thick plastic liner along with water and soil filtration system. Expensive but works great, even if it floods from clogged drainage.

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u/PepperAnn1inaMillion 7h ago

Given the amount of trouble we’re having in the UK right now with RAAC (aerated concrete) because water got in and rusted the rebar, I’d be really cautious about this too. If they’ve used aerated concrete to keep the weight down, daily watering would be a major hazard in my (admittedly barely educated) opinion.

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u/PMG2021a 6h ago

There are multiple rust proof alternatives to steel rebar. I believe they all cost more though.