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The Science of Bridge Collapse Prevention

toddatcw writes "In the wake of the Minneapolis Interstate 35W bridge collapse this week, Computerworld investigates ongoing research which could someday help to prevent future disasters. Acoustic emissions detection systems, which listen for the sounds of metal snapping on structures, are already sold and fitted. Likewise, a new generation of detector systems that monitor for tilting of bridge columns and piers are being designed, prototyped, and researched. 'Sound waves move more efficiently through solid objects than through air, making any sounds easier to listen out for, Tamutus said. "It's not amazing. It's simple. Doctors use stethoscopes all the time. If you put your ear on a train track, you can hear a train approaching from far away... The Sensor Highway II systems, which are portable and can be moved from bridge to bridge as needed, usually cost between $20,000 to several hundred thousand dollars each. Typically, evaluations take between one day and a week.'"

13 of 276 comments (clear)

  1. The bigger problem by weak* · · Score: 5, Insightful

    It was known well before the collapse that the bridge was in need of repairs. It seems that no public employee, elected or not, understands that prevention is better than reaction. New techniques to detect a heightened probability of failure are useful only if someone acts on the information once it is available.

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    The Schwartz space ain't from Spaceballs.
    1. Re:The bigger problem by GIL_Dude · · Score: 4, Insightful

      Get elected, then just try raising taxes to pay for something that might happen someday. Or, try to re-allocate funds from some bleeding heart program and see how far you get. People in general are not willing to fund repairs for things that might happen. It reminds me somehow of the little guy "Short Round" in Indiana Jones and the Temple of Doom jumping up and down on the footbridge yelling "strong bridge, see, strong bridge" just before starting to fall through the bridge. Obviously this is NOT FUNNY that this happened, but it just shows how people always want to think everything is fine right up until the time that it isn't fine.

    2. Re:The bigger problem by JonathanR · · Score: 4, Insightful

      )
      Get elected, then just try raising taxes to pay for something that might happen someday. Terrorism?
    3. Re:The bigger problem by penix1 · · Score: 5, Insightful

      It seems that no public employee, elected or not, understands that prevention is better than reaction.


      No it isn't...

      This may seem callous and cold in the wake of this incident but in fact it is cheaper (hence "better") for the state to react sometimes than to mitigate a hazard. It is simple economics. The federal cost share is 75% federal, 25% state. In catastrophic events, that split drops to 90 / 10, or at the discretion of Congress, 100% federal (Katrina is 100% federal). If the hazard you are attempting to mitigate would cost more than if it fails, then it is cheaper to let it fail. Of course, you run the risk to life and property when you do this so it is a huge gamble.

      States are cash strapped with the thousands of "unfunded mandates" the federal government places on them. Everybody want services but don't want to pay for them in higher taxes. Then you get pandering politicians running on "lower taxes" campaigns further reducing a states ability to operate properly. It is a wonder it took this long for something to happen.
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  2. How about this? by rolfwind · · Score: 4, Insightful

    Step 1: Stop nation building OTHER COUNTRIES
    Step 2: Start nation bulding OUR COUNTRY
    Step 3: No step 3. It doesn't have to be so complicated.

  3. Won't fix apathy and greed by ChromeAeonium · · Score: 3, Insightful

    As the old phrase goes, an ounce of prevention is worth a pound of cure. The technology's nice and all, but I'd saw the trick is getting people to look into this sort of thing, and take action, beforehand. I say this because in my area there was an old bridge that many people used regularly, however, it was a well known fact that it was deteriorating. The city, however, didn't want to spend the money to fix it, and it was years before anything was done (despite the fancy new road nobody wanted or needed that was built just minutes away). That bridge could have possibly collapsed, and everyone knew it. This new technology might make detection easier, but as long as the almighty buck is king, no amount of technology can compensate for human nature.

  4. In other words:The Science of Bridge Construction by viking80 · · Score: 3, Insightful

    Usually "The Science of Bridge Collapse Prevention" is called "The Science of Bridge Construction"

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    don't cut it off www.mgmbill.org
  5. Re:Some of the locals seemed to know... by Vellmont · · Score: 4, Insightful


    This smacks of criminal negligence - complete catastrophic failure in 4 seconds could not have been an undetectable condition.

    You have way to much confidence in science and technology. I think it's certainly possible that the inspections done didn't detect the problem with the bridge. Science isn't perfect, and there's always assumptions and things no one knows.

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    AccountKiller
  6. So it looks like were all in agreement... by weak* · · Score: 3, Insightful
    ...that someone we're paying with our tax dollars either fucked up or didn't care. Now what? Can we simply vote for better people? Of course not: history demonstrates conclusively that these better people don't exist, don't want the job, or go unnoticed (largely because the general public doesn't have the time or the means or the interest to assess the competence of prospective officials). So what do we do to put qualified people into positions responsible for our welfare, and hold them accountable once they're there?

    It's a hard question, so I think I'll just ignore it, in light of the sad truth that a month from now, no one (who doesn't have a personal connection to the tragedy) will care. To hell with "doomed to repeat it."

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    The Schwartz space ain't from Spaceballs.
  7. Re:ironic by Alastor187 · · Score: 4, Insightful

    Are sure that was written by an engineer?

    He says look at the WTC, it collapsed because of the lack of redundancy.

    What?

    Seriously, the building was hit by 150,000 lb aircraft carrying 20,000 gallons of flammable liquid. It was obviously never designed to withstand that kind of structural complication.

    However, for a minute lets say someone had enough foresight to add "resistance to impact from commercial aircraft" into the structural requirements. Why stop there? What about earthquakes, hurricanes, tornados, tsunamis, or meteorites?

    Where do you draw line? How much cost can you tolerate?

    It is not engineering that is overly concerned with cost to benefit ratios, that responsibility falls on management and/or accounting. If engineering comes up with two designs for a bridge, where one is under budget and lacks redundancy and the other is over budget and but incorporates redundancy, it is management or the customer that must decide what is most important.

    Now some people may say that engineering has an ethical responsibility to build the best product, which may be true. But how does one do that, by quitting their job every time that don't get their way? Or by building the better a better product with the lesser budget, that is working for free?

    While I agree that modern engineering has a lot less design tolerance. I think this is thanks to a better understanding of physics as well as better tools. So it is now possible to safely design bridge with a poor failure mode because we 'better' understand what drives the failure (I am not saying that poor failure modes are better).

    In this case I think the inspection process is more suspect than actual design. I think everyone would agree that the design had areas of concern. But no design is perfect and all bridges will eventually fail. That is why they are inspected on regular bases. How is it that this bridge was inspected in the last few year and no critical issues were found? Doesn't that mean that a better inspection process is needed?

  8. Re:ironic by macaddict · · Score: 4, Insightful

    disaster waiting to happen, just like the World Trade Center

    A disaster? WTF do you have to do to be considered a success for this guy?

    A fuel-laden commercial jet slams into a 110 story building (x2) and a little less than 3,000 people died.

    The buildings could have collapsed immediately and killed, what, about 20,000 people? But both stood long enough (56 minutes and 102 minutes) to evacuate most of the occupants. Sounds like a pretty damn successful building design to me.

  9. Re:Barriers/Lights by donaldm · · Score: 4, Insightful

    Taking into account all the factors that can cause a disaster is just about impossible. While it is possible to design something that is nearly disaster proof it can't be done with 100% confidence, because there are things that can occur that can be outside of the original design plan. Two simple examples are designing for a category 4 hurricane and then getting hit with a category 6 or designing for a richtor 5 earthquake and then getting hit with a richtor 7 earthquake.

    All that can be done is to have a flexible disaster prevention (eg. periodic bridge checks which actually were done) and a rescue program in place which from what I read about was quite good although to some who lost friends and relatives maybe not good enough. I would leave that to the investigation committee to comment on this.

    The problem with any disaster is it normally happens with little or no warning and sometimes so quickly people just cannot get out of the way. The question of "it could have been prevented" is rather mute after it has happened.

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    There ain't no such thing as proprietary standards only proprietary formats. Standards are by definition open.
  10. Re:Political by ktappe · · Score: 4, Insightful

    Is it not the easiest just to elect people who take care of things?
    If history is any judge, no, it apparently is not easy at all for the voting public to do that.
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