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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

#41

Post by pintxo »

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…

Someone else posted the NTSB video on the bridge: https://www.youtube.com/watch?v=J-VnWB4fiFk

I am fairly certain that a large majority of people, if they'd have had access to those images of the bridges structural members, would have stopped using it.

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

#42

Post by arethuza »

AdamN wrote: post #31
arethuza wrote: post #15

Earlier quoted context omitted.

"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?

Yes, I'm being "irrational" by some viewpoint, I know that.

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

#43

Post by dscottboggs »

bboygravity wrote: post #38
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.

Bridges do move some normally, yes. It may depend on the type of bridge though? Certainly suspension bridges do.

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

#44

Post by amanaplanacanal »

rob74 wrote: post #27
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…

A well-maintained (and well designed, but there's no reason to think the design was at fault here) bridge shouldn't collapse. Ever. "Appropriate maintenance" in this case would have been to periodically unclog the drains so the water can run off in a controlled fashion and not pool and corrode the supports. How expensive can that be? Instead, the bridge collapses (and they were lucky that no one was killed in the col…

I don’t know how things work in other countries, but in the US new construction is almost always funded with a big chunk of federal dollars (deficit spending), but maintenance has to be done out of your own state or local budget. The incentives are all fucked up.

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

#45

Post by bell-cot »

lucianbr wrote: post #32
bell-cot wrote: post #24

Earlier quoted context omitted.

> 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 succes…

Does the NTSB agree with you, and write lengthy investigative reports about most of the bridges which are successes?

Another engineering quip: "Any idiot can build a bridge that stands. But it takes an engineer to build a bridge that barely stands."

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

#46

Post by nkrisc »

lostlogin wrote: post #36
zeristor wrote: post #29

Earlier quoted context omitted.

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.’

I take that to mean there were no signs of imminent collapse, just sudden failure.

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

#47

Post by rini17 »

fh973 wrote: post #6

This is all interesting, but misses the point: the bridge collapsed due to a social (management, responsibilities, organization, ...) failure. Investigating the engineering story distracts from that, both in the video and apparently effectively as there is a NTSB investigation and not mentioning if any organizational review if the same rigor.

Grady does not miss the point, but repeatedly says he does not understand the social part. This calls for someone else with better expertise to do that kind of analysis.

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

#48

Post by shiroiushi »

thaumasiotes wrote: post #37
keiferski wrote: post #25

Earlier quoted context omitted.

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.

If you're going to use the political definition of "third world", then you need to include Switzerland. I'm sure that's not the type of country the OP was referring to. These days, almost everyone who uses this term is using it in the economic sense, since the Cold War has been over for decades.

Do you also complain when people use the term "decimated" and they aren't talking about killing 1 of every 10 soldiers?

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

#49

Post by Gare »

lostlogin wrote: post #36
zeristor wrote: post #29

Earlier quoted context omitted.

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.’

Warning in this context means something obvious to the unsuspecting user that collapse is imminent. Like a building creaking or buckling minutes or hours before finally giving way.

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

#50

Post by ThinkBeat »

Many western countries in general do not care for routine maintenance of infrastructure / buildings / water lines / busses.

Norway has to be among the worst.

It is not fun and glorious for a political administration to set aside $$$$ every year that will just go to people doing boring work that the voters will not be impressed with.

You dont see politicians "Under my administration we painted XX buildings, we did need maintenance of YY bridges, we replaced ZZ parts of the railway that would become problematic with time.

Rather: "Under my administration we opened up a new large hospital (because the other had near 0 maintannce for decades), we built 2 new bridges etc"

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