What Happened To the Bay Bridge? 407
farnsworth writes "Tony Alfrey has put together a fascinating page with some history, analysis, and possible explanations for what ultimately went wrong with the recent emergency repair of the San Francisco-Oakland Bay Bridge. The bridge has been closed for days and is not scheduled to open for days to come, hugely inconveniencing more than 250,000 people a day. His analysis touches on possibly poor welding, a possibly flawed temporary fix, and the absence of a long-term fix or adequate follow-up by Caltrans, the agency responsible for the bridge. Slashdot is a great engineering community; what other insights do you have on the bridge situation?"
still dead! (Score:4, Funny)
For several work mornings the headline on "the new" CNN.com has been "Bay Bridge still closed."
In my head I hear it in the voice of Chevy Chase.
"General Francisco Franco is still dead!"
Re:still dead! (Score:5, Funny)
Slashdot is a great engineering community
He must be new here;)
Re:still dead! (Score:5, Funny)
Re:still dead! (Score:5, Funny)
Aw, everyone knows Slashdot is full of experts. Even if we don't know what we're talking about, we'll still pretend to be experts. Well, until a real expert speaks up and makes us look stupid. :)
Re:still dead! (Score:5, Insightful)
Aw, everyone knows Slashdot is full of experts. Even if we don't know what we're talking about, we'll still pretend to be experts. Well, until a real expert speaks up and makes us look stupid. :)
Pshuh, I don't need an expert to make ME look stupid !
Speaking as the owner, I'm furious (Score:5, Funny)
Four years ago I bought that bridge along with a package of subprime mortgages to highly qualified homeowners.
And where did the retro-fit funds go? (Score:5, Interesting)
Re: (Score:3, Insightful)
Where did they go? Elsewhere.
Children have been pulling this scam since money existed and they were given money. Give them some lunch money and watch them go and spend it on something non-lunch related, then come back and cry to their parents saying they don't have lunch money. So you can be a heartless parent and make them go hungry and get laughed at by their friends but learn their lesson, or you can give them some more money so that their behavior is reinforced.
Obviously a child being hungry for one
Re: (Score:2)
Re:And where did the retro-fit funds go? (Score:5, Interesting)
Temporary fix insufficent (Score:3, Funny)
They should have used duct-tape!
Rushed (Score:2, Insightful)
Sure the commuters will have to wait a little bit longer while repairs are done, but it sure beats the mess they're in now.
Re:Rushed (Score:4, Informative)
Things like this can't be rushed, plain and simple. Carefully executed planning is what's needed to take on these types of projects.
What XPeter said.
On the gripping hand, they should see if there's anything left of the civil engineering group from the old Hydro-Electric Commission in Tasmania. The collapse of the bridge over the Derwent River when the ore ship Lake Illawara collided with it was repaired by them when the department of roads weren't up to the task. The old Hydro took their sweet time to fix it, but fix it they did and it's better than new (ship-repelling caissons were added). The size and type of that bridge and the treachery of the waters within which they worked make them similar cases.
small (Score:5, Insightful)
Re:small (Score:5, Funny)
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Or heaven forbid, paying down the national debt.
Re:small (Score:5, Interesting)
Depends on the rate of return you can get on other investments.
True story. I had a guy working for me who applied for a loan on a sailboat. This was a non-profit, so there were a lot of rich kids doing the noblesse oblige thing. Anyhow the bank calls, and afterward the guys says, "they turned me down".
"Why?" I asked.
"They screwed up. They said I didn't qualify because my income was only 40K."
"I don't pay you that much," I said.
"Actually 40K is my bi-weekly income, but I wanted to get a loan because my investments are returning higher than the loan interest rate."
What you want is the net value of the United States to increase as much as possible. You want the debt to go down relative to that figure. No major corporation *ever* tries to pay down all its debt. It would be insane, because they'd be paying opportunity costs. Just like my young friend, they don't worry about just one side of the ledger. They maximize their net worthy subject to whatever limitations liquidity puts on them. Naturally, this is not an option most of us ordinary mortals have.
What you really need to worry about isn't debt alone, but what you are using the liquidity the debt gets you to do. In other words, spending the money wisely. Spending on maintaining critical infrastructure *should* be a no-brainer. You don't say, "we're going to stop painting this very important bridge because we want to reduce our debt." That would be moronic. Likewise, even if you didn't have a nickel of debt, spending money on something that doesn't return anything is just as moronic.
Re: (Score:2)
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Infrastructure is primarily paid for by the individual states, not the federal government. What the US federal government does or does not spend is largely irrelevant; it is not as though the individual states have 'defense' as major line items.
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Amazingly, if the US were to stop picking fights with other nations in the world, they would find that they could safely reduce their military budget.
Determining a good balance between a formidable military that scares away any would-be enemies from even thinking about invasion or causing damage to the USA, and what is simply gilding the lily of military weapons, personnel, and training is something that certainly is worth arguing about.
There is also the tendency that when given the gift of a well trained and equipped military, that most politicians choose to actually use the military as a weapon to further their own political aims... whatever they may b
Re:small (Score:4, Insightful)
It was George Washington that sent U.S. Marines into northern Africa for the first foreign war. Please explain why anything more recent is any different than that action?
I believe that was Thomas Jefferson, not Washington. The Barbary Wars were in the early 1800s, after Washington had already finished his two terms.
However, I'll tell you exactly what's different between these wars.
1) Back then, the Barbary Pirates were attacking American vessels with American crews, and demanding payments. Iraq never attacked America. Yes, Saddam was violating some UN rules and not being terribly cooperative, but that could have been fixed with some cruise missiles and bombs, not an all-out invasion, for much less money and without distracting us from the task in Afghanistan. And Afghanistan never attacked us either, though Al-Qaeda did. That could have been taken care of by attacking Al-Qaeda directly in their caves and training camps, without having to take over the entire country.
2) More importantly, back in the 1800s, when we went to war, we fought to win, and didn't worry about civilian casualties. When America attacked the Barbary Pirates, they attacked them in their port cities like Tripoli, by bombarding the cities. They didn't worry about civilians, because the civilians were guilty of allowing the Pirates to stay there and run the place. In WWII, we also didn't worry much about civilians. We happily dropped tons of bombs on cities and killed civilians by the hundreds of thousands. It was their fault for allowing an evil dictator to take power over them, and we certainly didn't worry about them turning into terrorists later. We crushed them, and they became quite compliant afterwards. Now, we worry far too much about civilian deaths, which just makes it impossible to win a war.
Re:small (Score:5, Informative)
The situation in Afghanistan in 2001 was similar to the situation in Cambodia in 1970. Inside the capital of (Phnom Penh/Kabul), the (Royal Family/Taliban) ran things. Outside the city limits, the countryside was controlled by (the Khmer Rouge/various 2-bit warlords like the Northern Alliance). (The Royal Family/The Taliban) had effectively zero power and influence outside the capital.
The reason why bin-Laden was so far out in the boonies (couple hundred miles!!) in Afghanistan was, even the Taliban didn't like him. Pre-Soviet Invasion, he was just some radical kid with a big checkbook, nobody really important other than having close family ties with the Saudi royals. Even the mujahadim thought he was a nutball. His real influence? About as far as the distance between his pen and his checkbook. And of course when the US demanded the Taliban immediately turn over bin-Laden, the Taliban, having just enough police to clamp down on Kabul and about as much real military to provide a couple hours' target practice to the Northern Alliance, told the US they just couldn't do that. Not wouldn't, couldn't, as in, having no capability of doing a particular thing, in this case, handing bin Laden over. The US of course instantly informed the entire planet of the 'Afghani government's refusal to hand over bin-Laden. About the only people to really listen were inside the US. Everybody else already knew that 'Afghani government' is one of those contradiction in terms like 'military intelligence' and 'jumbo shrimp'.
Re: (Score:3, Insightful)
Please explain why anything more recent is any different than that action?
Please explain why George Washington doing it (or any other president for that matter) makes it 'right' in all instances?
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Just a comment on your disclaimer.
It's the middle east. They've always been at war with someone. They always will be. By putting yourself in their area, you're an enemy. There's no way to "win", especially where there is no organized enemy.
A requirement for entering any situation must be to have a clear cut expectation of what the goals are, and an exit strategy.
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It's not about democrats or republicans. It's not about liberals or conservatives. Both sides spend significantly more money than they have. It is a problem for all Americans, no matter what your political leaning may be.
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If infrastructure would stop breaking people, maybe the healthcare wouldn't need quite as much help. :)
Minnesota [cnn.com] - 13 dead, 145 injured.
Florida [francesfar...evenge.com] - 35 dead, 1 injured.
Washington [wikipedia.org] - 0 dead, 0 injured, 1 dog dead.
Indiana [chicagotribune.com] 25 injured
Massachusetts [wikipedia.org] 1 dead, 1 injured
Re: (Score:3, Insightful)
well your off in a lot of ways.
he USA is 300 million people in a land area the size of Europe who has a population of 700 million plus.
So not only are you off to start with you are making random assumptions. Sure there is a lot of engineering work that the USA needs to update. however since we have a fraction of the population that most land areas have we have to do more with less.
Besides having been through europe. The american system is at least 3 centuries more advanced than some of the roads, and bri
Re:small (Score:5, Insightful)
That's only if you count Alaska, which is disingenuous at best, given that it's huge, and almost completely unoccupied. Continental Europe occupies 3.9 million square miles, while the 48 contiguous US states occupy 2.9 million square miles. However, the population density of Europe is indeed approximately double that of the "lower 48" (181 people/mi^2 in Europe vs. 94.5 people/mi^2 in the US)
If we're only talking about the coastal regions, you'll find that the US East coast is almost continuously urban from Boston all the way down to Richmond. Europe has nothing that can compare to that sort of density.
The west coast is a bit more sparse, although California follows population patterns very similar to what you'd see in a typical European country.
Re: (Score:2)
"Are you from another country? The infrastructure here is fine."
By what standards, exactly? The people from other countries tend to have higher standards than our clueless denizens who can't be bothered to open an engineering text. How many US citizens graduate with advanced degrees in engineering? How many graduates of MIT and other top level schools are from India, Pakistan, China, or even freaking CUBA?
The infrastructure here does suck, because we keep electing one of two parties, each of which uses o
Comment removed (Score:4, Funny)
Lets see here... (Score:4, Insightful)
Re:Lets see here... (Score:5, Informative)
"In 2003, Californians sent $50 billion more to Washington in federal taxes than the state received in federal expenditures. Representing a slight increase from levels that have held steady for three preceding years, the Golden State’s imbalance set a new record for any state, surpassing the previous mark (set also by California, in 2000 and 2001) of $48 billion."
http://www.calinst.org/pubs/balance2003.htm [calinst.org]
Maybe if that weren't the case, California wouldn't be so broke right now.
Re:Lets see here... (Score:4, Informative)
Re: (Score:2)
Wrong audience (Score:5, Funny)
No, Slashdot is mostly made up of computer janitors; the greatest insight you'll get out of most of the posters here is, "hurrr durr, the bridge must've been running Windoze! LOL!", with maybe a little "omg the twin towers were collapsed by EXPLOSIVES!!!!"-style conspiracy theory and "THE GOVERNMENT IS BAD!!!" braindead libertarianism thrown in for color.
Re: (Score:2)
I accidentally picked the wrong moderator item, so I'm responding here to back out.
I would have picked Insightful.
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What engineering is really about. (Score:5, Interesting)
No, Slashdot is mostly made up of computer janitors.
I do get that feeling now and then.
Many years ago, I went to a serious engineering school. There, the final exam in a course in structural engineering was this:
At the final exam, each student had to design a link to attach two pins some distance apart. There were obstacles between the pins and the link had to go around then. The design was to be for a specified grade of aluminum and had to support a specified load. Students knew in advance what the exam would be, except for where the obstacles would be. For the exam, you sat at a drafting table, and turned in a drawing.
The link you designed was then machined out of aluminum by a machinist. It was put in a testing machine and placed under the specified load. If the link broke, you failed the course.
If the link didn't break, it was weighed. Lower weights yielded higher grades for the course.
This is how good structural engineers are trained. (I'm not one. I was in EE/CS, and we had a different make-or-break exam.)
Re:What engineering is really about. (Score:4, Interesting)
As do I, but the occasional insightful posts make the whole exercise worthwhile.
What school has that exam, by the way?
Re:What engineering is really about. (Score:4, Interesting)
Took a school like that in the Navy, six weeks on the mechanics of a disk drive. (The size of a footlocker, with hydraulic, mechanical, electromagnetic, and optical components. It held an amazing 10meg (not shabby for a 1964 era drive) and was built like a friggin' tank.) For the final exam you walked in and the whole damn thing was dismantled and spread out on 3-4 tables...
You had two days to put it back together and perform all the alignments - then it was plugged into it's electronics and the 'self test' button was pushed. If it passed, you did. If it didn't, you didn't - and got to repeat the entire school.
Don't even ask about the school on the drive electronics. Nearly a quarter of a century later I still have nightmares about that school.
Re: (Score:2)
No, Slashdot is mostly made up of computer janitors
Well janitors aren't usually asked to solve problems - they do boring repedative manual work, which is why they aren't paid so well.
he greatest insight you'll get out of most of the posters here is, "hurrr durr, the bridge must've been running Windoze! LOL!"
What I find particularly sad is that you've clearly just abused the community and they think you're kidding.
ith maybe a little "omg the twin towers were collapsed by EXPLOSIVES!!!!"-style conspiracy theo
Re: (Score:3, Interesting)
Your comment is painfully accurate. Thing is, Slashdotters were a lot smarter when I signed up 8 years ago. There have always been Linux obsessives, conspiracy wingnuts, and kneejerk libertarians, but even they had something worth contributing now and then. There was a lot of stupid noise, but every once in a while you could have a really interesting and informative conversation with some random stranger. Now it's all just flames, rants, and temper tantrums.
I blame changes in the moderation system. Original
Re: (Score:3, Insightful)
More likely, you just personally have gotten smarter and wiser.
Slashdot has always been filled with bogosity passing as "insight", it's always had karma-whoring (since moderation started), and it's always had trolls having a nice laugh at everyone's expense. If you were to criticize Slashdot for anything, it's not that it's gotten worse, but that its is going into middle-age without getting any better. It is stuck in that same mid-1990s adolescent "Windows drools, Linux rools, Gimmie warez" state forever an
Re:Wrong audience (Score:5, Insightful)
Re:Wrong audience (Score:4, Funny)
Re:Wrong audience (Score:5, Informative)
In interviews I've seen, the architects stated that the assumption was that any collision would involve a plane (specifically a 707) lost in the fog, flying slowly and trying to land. Such planes would not be fully loaded with fuel since they would be at the end of their trip, and they wouldn't be piloted by terrorists pegging the throttles at top speed.
The scenario envisioned was more like what happened to the bomber that hit Empire State building in 1945. It wasn't that big of a deal.
Re:Wrong audience (Score:5, Informative)
During a botched takeoff, the first thing a pilot does is to begin dumping fuel as fast as he safely can. Jet fuel is similar to kerosene, which evaporates quickly in the atmosphere, usually before hitting the ground.
Most aircraft cannot survive a landing with fully-loaded fuel tanks (unless the plane itself is carrying an unusually light passenger/cargo load).
Also, the flight patterns around Newark, JFK, Teterboro, and LaGuardia would all avoid lower manhattan, even in the event of a severe failure or navigational obstacle. Odds are, they'd end up in the meadowlands, the hudson river, or a residential area. Briefly browsing takeoff-related aviation accidents around NYC seems to confirm this.
The odds of a fully-laden jumbo jet hitting a building in lower Manhattan by accident are close to nil.
Re: (Score:3, Informative)
I'm pulling from memory here, but I think that they did consider fuel. However, the planes today hold more fuel, they did not account for the missing (destroyed) fireproofing, they did not account for the furniture getting piled up in one area and concentrating the fire, and I don't think that they conceived that the inner wall would be breached.
Government Bridge (Score:2)
A private one would have been more Ron Paul
There *IS* redundancy. (Score:4, Informative)
People use other bridges and the bart.
To say there isn't redundancy, is simply silly.
Caltrans Says (Score:5, Informative)
The engineering authority in charge of the bridge and repairs already gave their answer to this on the morning news (yesterday, I think):
They found the crack. They designed the "band-aid": the saddle, T-bar, rods, etc. They had it fabricated and installed.
In subsequent days, they went back up to look at how it was doing. They found that it was vibrating more than they thought it should: it wasn't as rigid as it was designed to be. They recognized that this would lead to fatigue and failure.
They began designing the improved "band-aid" and planned to install it sometime in coming weeks.
To their surprise, *perhaps* related to unusually high winds, the system failed sooner than they thought it could.
The completed their improved design and are now installing it. (And they are counting their blessings that nobody was killed: they got lucky, that way.)
-t
Re:Caltrans Says (Score:4, Interesting)
Re: (Score:3, Interesting)
This is what you call a rock-and-a-hard-place scenario.
Stuff suspended over people is the thing that gives the civil engineers I know nightmares. Closing a bridge like that gives traffic planners nightmares.
You put the two together, and there's a lot of pressure to do a little wishful thinking. That the emergency field repairs on the single most important piece of infrastructure in a major city are acting in an unexpected way is the kind of news nobody wants to hear. And so it's so easy to say, "well, w
Closing the bridge makes it 100% safe (Score:5, Funny)
If their goal was to improve the safety of the bridge, then they totally succeeded.
There simply isn't anything "wrong". (Score:2)
It is old, 73 years, and may take a few days to identify and repair especially after first attempt failed.
Who says anything is wrong?
This all seems perfectly normal.
(I like the fact that many people here would rather their be multi-billion dollar solutions, rather than this is simply how it is).
Re:There simply isn't anything "wrong". (Score:4, Insightful)
Re: (Score:2)
I am fascinated by this world of yours in which "shit happening" precludes something from having "gone wrong".
Welders are a scapegoat (Score:5, Interesting)
Seth
Re:Welders are a scapegoat (Score:4, Interesting)
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welds, even properly done welds, tend to be significantly weaker and more brittle than a typical solid piece of unwelded material. The subsequent temporary fixes that they tried failed before they were designed to which suggests that they may not have built in enough redundancy on the structure as they should have. It could just be a case where they over-estimated the strength of these welds and decided to cut a few corners on the design its self.
Re:Welders are a scapegoat (Score:5, Informative)
I strongly doubt that the welding is the culprit. "Faulty welding" doesn't happen on something of the scale of a bridge.
You're right on. If the author of the article would have watched any of the Caltrans news conferences, they would have answered some of his theories.
The weld that he claims failed was clearly described as only being tacked, not structurally welded. That weld wasn't supposed to hold the structure together, the tie rods were, which failed. One of the improvements they are making now is to replace the tacking with a structural weld, so that even if something broke, these pieces won't come apart. The other improvements center around reducing vibration, especially in the tie rods
Who wrote that article anyway? Some guy on the internet who looks at some pictures of the repair and thinks he knows what a bunch of engineers working on the problem didn't know?
Re: (Score:2)
My understanding is the welding isn't being blamed, but I'll be the first to admin I've not bothered to read more than this article about ... however ...
In the perfect world, more welders would always be added to speed up the process. But we do not live in a perfect world. You may live in a dream world, but thats not the one we live in.
I see, on a regular basis, 'trained and certified professionals' take shortcuts and break the rules. I know state road inspectors that will pass things that really are que
What happened indeed (Score:5, Informative)
Raids of Public Transportation Funds [transformca.org]
nearly $2.5 billion was diverted away from transportation programs [transportationca.com]
You dipshit - the bridges are funded by tolls (Score:3, Insightful)
Perhaps if the state...
Perhaps if you know what the fuck you were talking about. This is why it is pointless to listen to anobody on Slashhdot, 99% of the comments are bullshit.
All the bay bridges, except the Golden Gate, are managed be the Bay Area Toll Authority and funded by tolls. Educate yourself.
http://bata.mtc.ca.gov/ [ca.gov]
Meanwhile, in Segovia.... (Score:2, Insightful)
Meanwhile, in Segovia (Spain), the Roman aqueduct is still up & running :
http://en.wikipedia.org/wiki/Aqueduct_of_Segovia [wikipedia.org]
Without mortar, with just granite blocks on top of each other, it is more than 2000 years old.
I can't help but wonder when mankind began to suck at building anything that should last more than a few years....
Re:Meanwhile, in Segovia.... (Score:4, Insightful)
Re:Meanwhile, in Segovia.... (Score:5, Informative)
You have no clue what you're taking about. Roman legionaries (who were paid) and paid laborers were used to build Roman infrastructure.
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It would have cost too much to do it with slaves. They're not cheap.
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Great, they built a big stone bridge... now pass a container ship under it.
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The Segovia aqueduct needs maintenance too, unfortunately.
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Roman Aqueducts were made of stone. The bridges in San Francisco were made of steel.
Stone erodes. This takes a long time. The erosion can be seen on the original stones in the aqueduct you mentionned. It is happening, slowly but surely, and eventually, if not properly maintained, the aqueduct will collapse. (parts of it have already collapsed, and been repaired... it's in the Wiki you linked, even.)
Steel corrodes. Unlike erosion, corrosion happens relatively quickly. Again, with proper maintenance, it can b
Re: (Score:2)
Meanwhile, in Segovia (Spain), the Roman aqueduct is still up & running : http://en.wikipedia.org/wiki/Aqueduct_of_Segovia [wikipedia.org]
Without mortar, with just granite blocks on top of each other, it is more than 2000 years old. I can't help but wonder when mankind began to suck at building anything that should last more than a few years....
You have something of a point, sort of, but in addition to the problems pointed out by the other responses, you forgot to scroll down in that Wikipedia article and notice that the Aqueduct of Segovia has been reconstructed multiple times. Also note that we think of it as special because it's still there, whereas most other aqueducts collapsed 100-1600 years ago.
Re:Meanwhile, in Segovia.... (Score:5, Insightful)
Don't blame the three caltrans employees (Score:3, Insightful)
It took me a while to figure out but then I realized: CALTRANS only actually employes three guys.
Driving the 15 in San Diego, I wondered why there were all these construction sites with absolutely no one working. Eventually I pieced it together... CALTRANS only employs three guys and one of those has to hold the sign.
Sure, they could just do one tiny little roadwork at a time. But that'd completely give away the hundreds of millions CALTRANS budget is being spent on three construction workers with the rest going to hookers and blow. Instead, they dump cones everywhere, dig holes everywhere, then quickly move on to the next site. Sure, you'll never actually see a CALTRANS guy working but it sure as hell looks like they must have a lot of people doing the work if they can dig up that much crap and have roadworks every couple of hundred yards.
So, when judging the bridge collapse, try not to blame the three overworked guys. They're doing the best they can. Their job was to put up some cones, slap on some duct tape in the two minutes they had assigned, then get on to making somewhere else look busy. If you want to blame someone, figure out who spends the other 99.9% on those hookers and that blow. Imagine how much could be achieved if his habit went to pay for actual workers instead.
Re:Don't blame the three caltrans employees (Score:5, Informative)
Instead, they dump cones everywhere, dig holes everywhere, then quickly move on to the next site. Sure, you'll never actually see a CALTRANS guy working but it sure as hell looks like they must have a lot of people doing the work if they can dig up that much crap and have roadworks every couple of hundred yards.
Most highway work gets done at night. Late at night.
If you can figure it out, I have no doubt CA's dot.ca.gov website will show you where and when they're actively doing construction.
I drive around during the day and see cones.
I drive around at night and I see construction crews.
Closed for DAYS? Lucky California. (Score:4, Informative)
Re: (Score:2)
There is a huge difference between a bridge mostly used for long distance travel and a bridge 250,000 people use to get to their jobs every morning.
Difference in materials (Score:2)
I heard the problem was the weld between old and new steel. Temperature change caused the materials to contract or expand and, being slightly different, they changed at different rates, breaking the weld.
I don't understand why people drive into SF anyway (Score:2, Interesting)
Wind usually not a problem. (Score:3, Informative)
It's surprising that they had trouble there. That's a big, stiff truss span, with lots of cross-bracing. Those usually don't have serious wind problems. (The Tay Bridge disaster [wikipedia.org] was, of course, one involving a truss bridge. But it was badly designed and very badly fabricated.) The worst case for wind is a long, narrow, thin span. The Tacoma Narrows Bridge collapsed through that kind of failure, and the Golden Gate Bridge was vulnerable to it. In 1951, during high winds, the Golden Gate Bridge deflected enough that one side of the roadbed was 11 feet higher than the other. Stiffening trusses [flickr.com] were added under the span. (These are big trusses, each over 20' high, but the bridge is so huge that few people noticed the retrofit.)
In the 1989 quake, the Bay Bridge had an upper deck section break at the joint between the high truss span and the lower spans. That was an impedance mismatch - the two sections oscillated in different ways, and the stress at the transition point was enough to break bolts. When the Bay Bridge was designed in the 1930s, those problems weren't well understood, and could not yet be simulated.
The problem seems to be that the quick fix for the crack was underdesigned. That was recognized within days, and a second fix was under construction.
The damaged eyebar could be replaced, but that requires fabricating a new eyebar and some specialized tooling to take off the load from that whole eyebar chain during repair. This span will be torn down in a few years, when the new span is finished, so that may not be worth it.
Re:Lack of redundancy (Score:4, Informative)
There are four bridges running east/west over the bay, it just happens that there is only one in this particular (useful) location. Also, given that the Bay Bridge has to connect to Yerba Buena island, there's not really a lot of room for another one right next to it. So there is redundancy, but you have to deal with the physical realities of the area.
Re:Lack of redundancy (Score:5, Informative)
Actually, they are currently building another bridge right next to it. These fixes are all to a structure that they hope to retire in a few years.
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But only one leads to the Playtronics factory [imdb.com] where the MacGuffinn is held...
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You could always use a ferry to get to YB Island. When it comes to adding a second bridge, that's too small a population to worry about.
Re: (Score:3, Interesting)
I was under the impression that the bridge had to go through Yerba Buena not to serve the island population (who are only there because the bridge makes it convenient I imagine), but because the bay is too deep and without a firm bedrock to otherwise locate the middle section of the bridge securely.
Possibly that was only a concern when it was originally built, but regardless, you would essentially need to route it in the same path as otherwise you'd need a new landing point on the Oakland side and there's A
Re: (Score:2)
I am from Australia but looking at a map of SF it seems they has a similar problem to Sydney. They really need to kick the military off their prime waterfront real estate.
If I lived in Oakland and I had to get to the west side of the harbour I would drive to the harbour with a sea kayak and paddle the rest of the way. Its just a shame that the Navy seems to control the best place to put a boat in the water (duh).
Re: (Score:2)
In between D.C. and Baltimore we even have three parallel highways - I-95 and 295 and US-1. One might be closed but the other two will still be usable.
That's stretching it, even on a good day when all 3 are open!
(If you drive through/around DC even occasionally, you'll know that I'm not speaking in hyperbole. Also, there's been a whole ton of construction lately on all 3, which is making the beltway even more treacherous than it usually is...not helped by the fact that the people who drive on it seem to drive either 40 or 80 mph, with no regard to which lane they're doing it in. I swear that road was designed to maximize the number of accidents that occ
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In my experience most of the problems are in the northern half of D.C.'s Beltway. The area between D.C. and Baltimore might slowsdown but it never completely stops (except accidents of course). And Baltimore's beltway is good except for the area around I-83 (which is a poor design).
A couple times I've suggested extending I-85 up to Philadelphia and beyond, so as to provide an alternate route for traffic (especially truckers who are going straight through from Richmond-to-Philly without stopping), but neit
Re:Lack of redundancy (Score:5, Informative)
The Bay Bridge is not the only way from Oakland to San Francisco, there's the Richmond-San Rafael bridge to the North and San Mateo bridge to the south. There's also BART and various ferries and worst case scenario a trip through the South Bay and then up the peninsula. There's lots of ways into the city even if one of the bridges is out of service for some reason. The past two labor day weekends the Bay Bridge was shut down for repairs (the latest of which apparently caused the current problems).
The positioning of the Bay Bridge is limited by the layout of both San Francisco and Oakland. The Bay Bridge already spans one of the narrowest points between the cities and is bisected by Yerba Buena Island to reduce the effective length of the individual spans. There's nowhere else to really put another bridge in the area. There's no other spots with convenient freeway locations on both sides of the bay which would require whole new sections of freeways be build which means buying out a whole bunch of land that people already live on and a host of other problems. This construction would be in addition to building a whole new bridge.
Re:My insight (Score:5, Informative)
The Oakland Bay Bridge isn't much of a landmark, really. In any case, it is *extremely* important to note that the western span of the Bay Bridge, which is a suspension bridge, is perfectly sound, as is the landmark (but less used) Golden Gate Bridge. All of these problems are with the eastern span, which is a cantilever bridge.
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I agree it is important. It keeps drivers from clogging up my train ride every morning. But it isn't a "landmark" in the sense that tourists don't go to look at it. (Except for the dumb ones suckered by locals saying "it's being repainted...the gray is the primer.")
MY insight, as an engineer (Score:3, Insightful)
The real problem is that we should recognize that bridges, and especially landmark bridges, stay standing indefinitely and should therefore quit designing the damn things with puny 50-year design lives!
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It's how the state balanced their budget.
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Forgot to RTFA, eh?
Re:No worries about the Bay Bridge! (Score:4, Funny)
Bridges aren't that expensive, it's the assembly and installation that kills you.
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I suspect that California educated engineers had a lot to do with the problem. A panel had to decide how to fix the problem. The panel was composed, by law, of one gay, one lesbian, one transvestite, one Mormon, one Moslem, one Black, one Hispanic - the list goes on and on.
You REALLY don't know how things work in California.
We got rid of the Mormon after the Prop 8 debacle.