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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

#101

Post by EricE »

philistine wrote: post #77
mc32 wrote: post #73

Earlier quoted context omitted.

Its grift. Why does the US have to spend money on military aid to first world countries, even if a very sizable chunk is spent on American weaponry? That money could be spent on maintenance rather than fattening our MIC. NGOs are similar. In theory they sound good, the leaders can pull sizable salaries, eclipsing any congresspersons earnings and they are incentivized to keep the bad thing happening—if they solved the…

To understand why the US government spends so much on rich countries, you can’t just think in economic terms, since that’s not what why the US government is doing it. The reason is geopolitical. It is seen as necessary to give money to allies to prop up their military so the US hegemony can be maintained. Adversaries (China, Russia, Iran) need to be made afraid not only of US might, but also of Allies’ might. So the…

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

#102

Post by EricE »

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…

The Pinto thing was dramatically overblown. And seriously set back the acceptance of small cars in the US. For a supposed environmentalist and consumer advocate, Ralph Nadar did FAR more harm than good by grifting off a bunch of sensationalist poppycock. That he's still looked upon as some sort of folk hero is beyond disgusting and just shows how gullible people continue to be paying attention only to the sensationalistic superficial propaganda and not looking deeper.

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

#103

Post by jibe »

hi-v-rocknroll wrote: post #33

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 brid…

More context:

About ARTBA

The Washington, D.C.-based American Road & Transportation Builders Association (ARTBA) is a non-partisan federation whose primary goal is to aggressively grow and protect transportation infrastructure investment

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

#104

Post by bluish29 »

greggsy wrote: post #80
hi-v-rocknroll wrote: post #33

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 brid…

Those states also have some of the fewest bridges, with the exception of Texas, which has the most of all states, and double the second place state (Ohio). That said, Ohio is 41 times smaller… So many ways to dice this information and I don’t even live in the US. https://www.statista.com/statistics/190386/number-of-road-br...

Texas is about 6 times bigger than Ohio. Texas is approximately 678,052 sq km, while Ohio is approximately 106,056 sq km.

The population of Texas is around 25.1 million people compared to 11.5 million in Ohio, a difference of 13.6 million people. That means about 2 times population wise.

I don't know by which size metric it is that ohio is 41 times smaller than texas?

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

#105

Post by icegreentea2 »

kube-system wrote: post #97
pintxo wrote: post #41

Earlier quoted context omitted.

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.

Most people are unable to accurately diagnose a bridge structure other than "yeah looks rusty". And if that were the case, they wouldn't be driving much of anywhere in that part of the country, which is called the "rust belt" for a reason. Pittsburgh has a very high number of bridges, if you go anywhere in that city and you don't want to cross a rusty bridge, you can't go very far.

There's rusty, and then there's "I can see daylight through the steel".

I think most people can accurately diagnose that as an actual, real problem.

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

#106

Post by kube-system »

icegreentea2 wrote: post #105
kube-system wrote: post #97

Earlier quoted context omitted.

Most people are unable to accurately diagnose a bridge structure other than "yeah looks rusty". And if that were the case, they wouldn't be driving much of anywhere in that part of the country, which is called the "rust belt" for a reason. Pittsburgh has a very high number of bridges, if you go anywhere in that city and you don't want to cross a rusty bridge, you can't go very far.

There's rusty, and then there's "I can see daylight through the steel". I think most people can accurately diagnose that as an actual, real problem.

That isn't an uncommon sight around Pittsburgh. Whether or not it is an imminent structural issue depends on where the holes are.

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

#107

Post by michaelt »

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?

> It's likely that you live in an area with similar mortality risk from air pollution.

They're not really equivalent, unless you've got a high-risk condition like asthma.

Statistically speaking, a 100% chance of losing one year of lifespan (out of the 76 years an American can expect) is a greater mortality risk than a 1% chance of instant, immediate death.

In fact, if you're aged 26, a 1% chance instant death has half the mortality risk - and the older you get, the better it looks.

However, if you look at humans' revealed preferences, people would much rather lose one year of lifespan than take a 1% chance of losing their entire remaining lifespan.

Mortality risk isn't a very good predictor of human preferences, it turns out.

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

#108

Post by ourmandave »

hi-v-rocknroll wrote: post #33

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 brid…

I was going to say they were sounding the alarm about bridges nation wide years and years ago.

They finally passed an infrastructure bill which hopefully includes fixing 'em.

I know they've been replacing a lot on I-80 in IA.

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

#109

Post by samatman »

more_corn wrote: post #98

This is why I think nuclear power is a bad idea. Paying back a multibillion dollar investment takes decades. Operating costs eat into profits. The financial incentive is to run them as cheaply as possible for as long as possible. In a place where there’s a strong work ethic and good maintenance history that might be fine. Look around at your infrastructure before climbing on the nuclear bandwagon.

A better comparison for nuclear power is the airplane industry. No one goes into the bridge running plant every day and runs the bridge for a living, with several people assigned to run a daily checklist on said bridge.

But it's still not a very good comparison, because airplanes, due to their very nature, can't be designed to fail safe. Nuclear power plants can.

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

#110

Post by bobthepanda »

throwaway211 wrote: post #91
tiagod wrote: post #64

Earlier quoted context omitted.

It's a suspension bridge. And a solid one :) Takes 6 lanes of traffic and whole trains on the bottom.

Trains cross bridges easily as they're either balanced with each half on each side, or half on and half on ground. And other time's just between these stable points. Furthermore, trains run on tracks which reduces chance of turning acceleration.

Yes and no.

Railways work well in the center of bridges. One bridge that violates this principle is the Manhattan Bridge; it was built before we had fancy engineering simulations or much experience with railway suspension bridges at all, and so the lower deck is a pair of railway tracks on either side of a roadway.

This unusual design is very stressful on the bridge and has resulted in expensive rehabilitation programs.

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