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Comment by pcl | Hacker News Reader

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 all in China (as are all but two of the 24 in the "under construction or planned").

https://en.wikipedia.org/wiki/List_of_longest_suspension_bri...

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The thing that stuck out to me was this:

> The 2,890-metre-long structure, which took more than three years to complete, reduces travel time between the two sides of the canyon from two hours to two minutes.

Pretty impressive. I feel like things in the US take a lot longer and cost a lot more. The prime example is the second avenue subway extension which has been planned since 1920. But I just searched for a few significant bridges like the Gordie Howe bridge which took about 7 years and 6.4bn Canadian (connects US and Canada). And this bridge which seems a lot more of an engineering feat took 3 years and 8 months and cost between $280 to $292 million

https://en.wikipedia.org/wiki/Second_Avenue_Subway

https://en.wikipedia.org/wiki/Gordie_Howe_International_Brid...

https://www.barstoolsports.com/blog/3553875/the-new-tallest-...

Chinese civil engineers, and engineering orgs, are good because they get a lot of practice.

In the West, and especially in the US, individuals and orgs don't get practice, so when they finally do get a new contract they have to stumble around for 5-10 years figuring out all the institutional knowledge that was lost.

By the time they figure it out, the project is over budget, so it gets canceled, and then it's 20 years until the next half-hearted attempt. Lather rinse repeat.

At root, a lot of this stems from a "managerial" mindset in which people and skills can simply be "reallocated" on a dime. They can't. You can't uproot trees all the time. You plant one and then it grows over multiple human lifetimes.

To say nothing of the NIMBYism. To acquire the land for use, you have to fight some armies of lawyers retained by a population with a lot of disposable income. (Yes, the US for all her problems has the biggest pool of disposable income in the world)

There's no NIMBYism in China, so that's a huge barrier that they don't have to worry about.

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 town without re-opening negotiations which might cost billions."

> 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 project manager for SNCF

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

I think the lesson here might be to solve your problems on a more local scale, as the fit of the solution is as important as checking the boxes.

What works in Japan works in Japan because it was a solution built for the problems, politics, and people of Japan. Sometimes there are lessons we can take from projects in other countries, other times it turns out like Cali HSR where the proposed 'foreign' solution might be logical but not politically tenable.

The problem isn't physically building the rail, the problem is the legal framework in which governments operate in. Multiple rounds of environmental impact statements, eminent domain lawsuits, preferred contractor RFP's, zoning, permitting, endless red tape...

>> The 2,890-metre-long structure, which took more than three years to complete, reduces travel time between the two sides of the canyon from two hours to two minutes.

The construction timeline and travel improvement are comparable to the New River Gorge bridge, which was completed in the US in ~50yr ago back when systems were structured to and the people who ran them actually were capable of producing results.

Freakonomics just had an episode about how China is run by engineers, who get things done, while the US is run by lawyers, who prevent things from getting done.

This is the central thesis of Ezra Klein's "Abundance" book. Basically, things like this (or high speed rail, or public housing) don't get built in the USA because the government has hamstrung itself with so many rules and regulations that it becomes prohibitively expensive and/or tied up in lawsuits.

Places like China, for better or worse, are not burdened with the problem of making sure every constituency is accommodated.

As a bridge Carpenter, you are correct. I have never seen a construction project of that size for that price completed in that amount of time in the USA. Not even close. I've done projects that are worth over 20 billion today. I've done projects as small as a sidewalk repair. There's no way you can turn out that scope of work for that price at that scale in America it's not even close. They have to be lying about the budget there's no way.

> 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.

Yeah, I know it doesn't matter how high the actual bridge is, just the length and pylons, but it feels like it matters!

More height, stronger winds. It matters.

Is this true? Does the center of a canyon have higher wind speeds than the edges of that canyon? And what about gusts? I'd assume that boundaries are more turbulent.

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.

I understand the point being made, and it's a valid one. My point, though, is along the lines of "engineers/tech-minded folk often miss the bigger picture". Yes, from an engineering perspective, it doesn't matter a whole lot how far the bottom of the valley floor is from the bridge (though I'm sure it matters some during construction).

But the "user experience" of someone driving over the bridge is vastly different, to the point where I know specifically of some people who wouldn't be willing to drive over it, and it's not "hyperbole" to point out how high this bridge is compared to the ground below.

What hyperbole?

All I'm seeing is fairly straightforward fact-based announcements. "The tallest bridge has opened - here it is." If that doesn't interest you, fine... but the reports are not hyperbole.

You're not a bridge Carpenter and it shows. .

This project is beautiful. This is an incredible work of art. It might not be the longest, but have you ever tried to pull cable over 2,000 ft hole? Have you ever seen what it takes to actually do those columns? The work looks nice very nice design. It fits with the landscape very well. And the fact that it cost only 140 million is an incredible. For a comparison if you look up one of the bridges I did. We spent 280 million on this We spent 280 million on this

I-91 Brattleboro Bridge | FIGG Bridge Group https://share.google/LKxgk1aEWh9gSIGhD

I don't know how to edit but the original budget for the bridge was only supposed to be like 50 to 70 million. Every single day there is an RFI.

I'm glad I clicked your link though. That I-91 bridge is beautiful.

Years ago I remember reading about an economist who stated something like, "the best way to stimulate an economy is to pay people to dig holes and then fill them in." (I wish I remember who said that.)

In modern times, that translates to paying people to build roads and bridges. Why pay people to sit on their butts and eat bon-bons when you can pay them to get something of value?

In more tangible terms, building infrastructure does elevate peoples' situations.

That was Keynes I think

I feel like the metric needs to be "greatest distance of road from solid ground" or "greatest distance from linear interpolation between ground attachment points".

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