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Highest bridge unveiled at more than 2,000ft above ground

independent.co.uk

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Re: Highest bridge unveiled at more than 2,000ft above ground

#181
post #166
post #81

Earlier quoted context omitted.

Yup, similar number of slaves too. https://en.wikipedia.org/wiki/Demography_of_the_Roman_Empire https://www.walkfree.org/global-slavery-index/country-studie...

That website has the US at 3.3 slaves per thousand people compared to China's 4.0.

You're catching on.

Re: Highest bridge unveiled at more than 2,000ft above ground

#182
post #64

I really don't understand all the hyperbole around this bridge. It's a suspension bridge, so the relevant bits are at the pylons, which just happen to be on either side of a huge canyon. It clocks in at #14 on Wikipedia's list of longest suspension bridges, with a main span that is 603 meters shorter (2023 meters vs 1420) than the longest. More interestingly, to me at least, is the fact that 31 of the longest 50 are…

> I really don't understand all the hyperbole around this bridge. It's a suspension bridge, so the relevant bits are at the pylons I understand what you're saying, but the experience is quite different for the people driving over it compared to a bridge where it isn't a 2000 foot drop.

I think the point being made is that if you followed two ridgelines that make up a valley up to a common summit you could just jam a plank in there. You've got the world's highest bridge. It's only 4 ft long, but it is technically a bridge.

I'd be more interested to know how they raised individual components into place. But I presume they just started with small cables, then used those to raise larger ones into place over time.

Re: Highest bridge unveiled at more than 2,000ft above ground

#184
post #155

Earlier quoted context omitted.

I hope the engineering team were riding in the trucks.

To punish them for building a cool bridge or?

It's only a punishment if the bridge falls down. But if someone is making truck drivers drive heavy trucks out onto a bridge to "test" if it will stand up under the load it only seems fair to me that the engineers who designed and built it take the risk alongside them.

Re: Highest bridge unveiled at more than 2,000ft above ground

#185

Earlier quoted context omitted.

> reduces travel time between the two sides of the canyon from two hours to two minutes. Think of it this way. Every 2 hours round trip to 2 minutes saves imported fossil. For trucking/freight that's like ~$80 of diesel both ways. PRC construction workers, though less abundant is cheaper than it ever will be. So best time to build infra is always now, especially one that reduces long tail imports. Every piece of infr…

Yes, but on the other side of the coin is the pending maintenance for all of these projects. You don't just build a road, rail or bridge anad then be done with it. They all require upkeep. If the project itself was a jobs program masquerading as a infra, they'll just let all these fabulous projects rot as it won't make sense to keep them up.

TBH potential future problem, scales to whether/how much construction industry get captured to point where maintenance costs is onerous. Developed west forgets, upkeep doesn't have to be expensive to defer which snowballs costs. The broader consideration for PRC is they are per capita, infrastructure POOR, i.e. less unit of infra in variety of categories per capita - there simply isn't that much excess infra relative to population.

Some of the bad investments won't pay back, will get abandoned with demographic change (baked in lower utilization when population drops), but IMO infra serves 10s millions, cuts millions of barrels of oil imports has good chance of paying for itself. Like 2hour -> 2minute infra for 2B rmb = 0.1% of Guizhou GDP. Seems like a no brainer.

Re: Highest bridge unveiled at more than 2,000ft above ground

#186

Earlier quoted context omitted.

> reduces travel time between the two sides of the canyon from two hours to two minutes. Think of it this way. Every 2 hours round trip to 2 minutes saves imported fossil. For trucking/freight that's like ~$80 of diesel both ways. PRC construction workers, though less abundant is cheaper than it ever will be. So best time to build infra is always now, especially one that reduces long tail imports. Every piece of infr…

Why is construction cheaper than it ever will be? Because wages are rising in China?

Undereducated workforce willing to do hard construction decreasing -> wagse rising. There's still big/experienced construction work force, build while it's cheap, build bigger and more than you have to etc.

Re: Highest bridge unveiled at more than 2,000ft above ground

#187
post #155

Earlier quoted context omitted.

I hope the engineering team were riding in the trucks.

To punish them for building a cool bridge or?

If you see it as a punishment to be the first to cross the bridge that you designed, then you should probably be increasing the factor of safety in your calculations and the number of site checks you conduct.

Re: Highest bridge unveiled at more than 2,000ft above ground

#188
post #163

Earlier quoted context omitted.

I know it would be attacked politically, but I wish in the US we would be more open to hiring foreign firms for these kinds of projects. Could we have high-speed rail if we just asked some French or Japanese company to build it for us? And we should structure contracts with them in a way that keeps the plans from being changed for political reasons. "Sorry state senator, we can't alter the route to pass through that…

> Could we have high-speed rail if we just asked some French or Japanese company to build it for us? No. Please see SNCF (French rail company)'s involvement in California's high speed rail project. https://www.nytimes.com/2022/10/09/us/california-high-speed-... October 9, 2022 "How California's Bullet Train Went Off the Rails" The (foreign) company's recommendations [...] were cast aside, said Dan McNamara, a career…

So I guess we have to not only hire the foreign companies, but also listen to them.

Re: Highest bridge unveiled at more than 2,000ft above ground

#189

Earlier quoted context omitted.

> reduces travel time between the two sides of the canyon from two hours to two minutes. Think of it this way. Every 2 hours round trip to 2 minutes saves imported fossil. For trucking/freight that's like ~$80 of diesel both ways. PRC construction workers, though less abundant is cheaper than it ever will be. So best time to build infra is always now, especially one that reduces long tail imports. Every piece of infr…

Why is construction cheaper than it ever will be? Because wages are rising in China?

Probably their aging demographics?

Re: Highest bridge unveiled at more than 2,000ft above ground

#190
post #8

I knew it was going to be China. China's infrastructure building is beyond impressive. I always come back to this map of China's high speed rail built in 16 years (2008-2024) [1]. China is actually run by a meritocratic bureaucracy rather than the dumbest of people who do nothing more than sell pardons, run crypto scams, transfer government funds to the wealthiest of people, pander to religious hallucinations and sel…

I, too, am jealous of China's high speed railroads. However, on the whole, China has overbuilt their infrastructure, and that may not look so smart in 40-50 years when the maintenance bills start coming due.

So, perhaps 2020s China ~ 1950s US demographics. The bridges that recently collapsed in the US (2024 Baltimore/Francis Scott Key Bridge and 2007 Minneapolis I-35W Mississippi River Bridge) were built in 1964 and 1972-1977 respectively.

Noone has yet compared the Chinese construction times/costs to the replacement Baltimore Francis Scott Key Bridge: cost ~$2b, estimated October 2028. Will have 600ft bridge towers, 1600ft main span (increased from 1209ft), total span length 3300 ft, improved pier protection. Surprised they didn't add a freight rail link.

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