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Fern Hollow Bridge should have been closed years before it collapsed

practical.engineering

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Re: Fern Hollow Bridge should have been closed years before it collapsed

#31

Post by AdamN »

arethuza wrote: post #15
dmurray wrote: post #12

If you knew all this, would you have avoided driving over the bridge? Would you have wanted the local government to close it indefinitely awaiting repairs? Let's say it would collapse with 100% certainty randomly in the next three years, and you're in the danger area for 2 minutes, with a 20% chance of fatality (in fact, nobody died). That's still around a one in 4 million chance any given trip kills you, about the s…

"Most people would accept that level of risk" I wouldn't and I definitely wouldn't if I had other people in the car.

It's likely that you live in an area with similar mortality risk from air pollution. Is there a reason not to move to an area with lower risk from air pollution?

Re: Fern Hollow Bridge should have been closed years before it collapsed

#32

Post by lucianbr »

bell-cot wrote: post #24
MaxikCZ wrote: post #14

Earlier quoted context omitted.

So its okay that bridges in US fall, even when being inspected dozen of times and being urged for repairs every time, because other countries have it worse? Why not compare to country where bridges dont fall at all?

> Why not compare... On the engineering side - you learn far more from analyzing failures than from analyzing successes. On the social side - there's nothing mysterious about how the US bureaucracy failed here. Briefly contrasting that with Utopialand (where the society & government are different, and bridges never fall) can work as journalism. Or as a rebuttal to "failures will always happen" doomsayers. But the uti…

> On the engineering side - you learn far more from analyzing failures than from analyzing successes.

This is just sophistry. You won't learn how this collapse could have been prevented, or how to prevent others like it, by studying countries where infrastructure is worse. You're already doing better than those places, and still it's not enough.

Also, I'm pretty sure engineering schools study both failures and successes. It is incredible to me that someone would honestly believe studying bridges that have not fallen is useless.

Re: Fern Hollow Bridge should have been closed years before it collapsed

#33

Post by hi-v-rocknroll »

For context, there were 42,391 structurally deficient bridges in 2023.[0]

16 of the worst are in LA county and several see 300k trips daily, including one carrying the 405.[1]

0. PDF https://artbabridgereport.org/reports/2023-ARTBA-Bridge-Repo...

1. https://artbabridgereport.org/state/ranking/top-bridges

EDIT: States with the least % of SD bridges: AZ, NV, TX, DE, and UT.

WV and IA have the most at almost 20% SD bridges respectively. (1 in 5!)

EDIT2: Raw data https://www.fhwa.dot.gov/bridge/nbi/ascii.cfm

Re: Fern Hollow Bridge should have been closed years before it collapsed

#34

Post by AdamN »

speakspokespok wrote: post #9

I just spent the last 4 years living in a series of countries that Americans would call ‘3rd world’. Places where proper funding of infrastructure, let alone inspections are so far below US metrics of adequate, they’d legitimately scare you. Bridges and overpasses that exist until they break and the people die. People call out to God for justice! But all that infra is then rebuilt the same way if it’s rebuilt / when…

No need for the condescension. Many of the people here don't even live in the US anyway.

Re: Fern Hollow Bridge should have been closed years before it collapsed

#35

Post by thaumasiotes »

beAbU wrote: post #20
dmurray wrote: post #12

If you knew all this, would you have avoided driving over the bridge? Would you have wanted the local government to close it indefinitely awaiting repairs? Let's say it would collapse with 100% certainty randomly in the next three years, and you're in the danger area for 2 minutes, with a 20% chance of fatality (in fact, nobody died). That's still around a one in 4 million chance any given trip kills you, about the s…

Yeah it's exactly this mentality that resulted in the Ford Pinto scandal of the 70s. How does that 1:4M probability change when you commute over the bridge twice a day? Humans are notorious for being bad gauging risk, and we very often make the mistake that past success means lower risk of future failure, which for a deteriorating bridge is exactly the opposite of what's going to happen. In my opinion bridges shouldn…

> How does that 1:4M probability change when you commute over the bridge twice a day?

You can get a good sense of this from the equivalence listed immediately after the odds:

>> That's still around a one in 4 million chance any given trip kills you, about the same as 30 miles of driving

So it'd be closely analogous to driving a 30-mile commute twice a day. How much risk do you feel that involves?

Re: Fern Hollow Bridge should have been closed years before it collapsed

#36

Post by lostlogin »

zeristor wrote: post #29
m2f2 wrote: post #8

Same stuff for the Genoa, Italy bridge (Ponte Morandi). Everyone running on that would feel vibrations and "repairs" were just lipstick on a ugly face, until it finally collapsed, with 43 dead. Surprisingly, or not so, no one was found guilty, not even the inspectors that didn't report the ongoing damages, just because "it would be too costly to rebuild it, and profits of the highway company (1) in charge of it would…

As the video states this was flagged by inspections 14 times over 7 years or so. There's even inspection reports of one of the cross supports rusted through and disconnected, a cable taking some of the strain. At the very least the bridge should have just been closed, as unsafe.

> As the video states this was flagged by inspections 14 times over 7 years or so.

And the article starts by stating that the collapse was ‘without warning.’

Re: Fern Hollow Bridge should have been closed years before it collapsed

#37

Post by thaumasiotes »

keiferski wrote: post #25
speakspokespok wrote: post #9

I just spent the last 4 years living in a series of countries that Americans would call ‘3rd world’. Places where proper funding of infrastructure, let alone inspections are so far below US metrics of adequate, they’d legitimately scare you. Bridges and overpasses that exist until they break and the people die. People call out to God for justice! But all that infra is then rebuilt the same way if it’s rebuilt / when…

This viewpoint is funny, because if you go to many places in Eastern Europe that Americans likely consider "behind", the infrastructure is far, far superior to anything in the US. In my experience, pretty much every developed country has better infrastructure than the US.

Eastern Europe is pretty much by definition not "third world". Third world would be Africa, maybe the Middle East and Southeast Asia.

There's a wide range of circumstances there, which makes sense since "third world" was a political designation, not an economic one.

Re: Fern Hollow Bridge should have been closed years before it collapsed

#38

Post by bboygravity »

m2f2 wrote: post #8

Same stuff for the Genoa, Italy bridge (Ponte Morandi). Everyone running on that would feel vibrations and "repairs" were just lipstick on a ugly face, until it finally collapsed, with 43 dead. Surprisingly, or not so, no one was found guilty, not even the inspectors that didn't report the ongoing damages, just because "it would be too costly to rebuild it, and profits of the highway company (1) in charge of it would…

Vibrations on a bridge are not normal?

I'm asking because I've been in standstil traffic (in my car) on the Lisbon "golden gate" type bridge and that thing was freaking bouncing up and down from traffic on other lanes.

Re: Fern Hollow Bridge should have been closed years before it collapsed

#39

Post by adrianN »

dmurray wrote: post #12

If you knew all this, would you have avoided driving over the bridge? Would you have wanted the local government to close it indefinitely awaiting repairs? Let's say it would collapse with 100% certainty randomly in the next three years, and you're in the danger area for 2 minutes, with a 20% chance of fatality (in fact, nobody died). That's still around a one in 4 million chance any given trip kills you, about the s…

The average American driver includes drunk and tired drivers who play on their phone while speeding. The numbers for sober people driving reasonably e.g. on their commute are probably better.
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