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Are there any experts here who can elaborate on whether Professor Gentile's acoustic testing of the bridge's cable stays may have had any negative effect on its

by lqet 8y ago

Are there any experts here who can elaborate on whether Professor Gentile's acoustic testing of the bridge's cable stays may have had any negative effect on its stability? I found this paper on the method: https://www.ndt.net/article/jae/papers/20-083.pdf https://www.ndt.net/article/jae/papers/20-083.pdf E: as mentioned below, the method is completely passive.

hypertexthero 8y ago
You may want to get in touch with [Professor Raimondo Betti][1], who [I spoke][2] with at Columbia University prior to a talk he gave about his research on [a bridge cable corrosion monitoring system][3]. He was optimistic about the ability of his (from my understanding, passive) sensor system in helping prevent these tragedies, but pessimistic about the political will to apply it to bridges. [1]: http://civil.columbia.edu/raimondo-betti http://civil.columbia.edu/raimondo-betti [2]: https://www.simongriffee.com/notebook/GRS-20151015-100821/ https://www.simongriffee.com/notebook/GRS-20151015-100821/ [3]: https://www.youtube.com/watch?v=cP1CfGVVXO4 https://www.youtube.com/watch?v=cP1CfGVVXO4
- lqet 8y ago
  Many thanks! Just out of curiosity: why was he pessimistic about the political will to apply this method? Because politicians fear the results?
  - hypertexthero 8y ago
    I am not sure, but that sounds right. This was a few years ago and my memory may be faulty, but I remember him saying that it would probably take the collapse of a large bridge like the Brooklyn or George Washington bridges in NYC before the authorities in the city would consider using the system.
  - jandrese 8y ago
    From a political standpoint you are spending money that might tell you that you need to blow your budget on rebuilding some infrastructure right now. Bridge collapses are so rare that nobody thinks it will happen to them. Just ask the people of Minneapolis.
throwaway5752 8y ago
Be super careful with that line of thought: it is precisely what they will use to deflect blame from the construction, engineering, and maintenance issues. "The bridge wouldn't have failed if it weren't for that pesky diagnostic procedure that also happened to raise all sorts of problems about corrosion and structural integrity" edit: also - not an expert but interested and somewhat informed - this is a very common structural engineering technique and should under no circumstances, ever, lead to this kind of outcome on a sound structure.
- SolarNet 8y ago
  Also Italy has a (recent) history of prosecuting scientists who attempt to give their opinion (even if it isn't listened to). If I was an Italian scientist I would stay far away from predicting anything to or for the government. http://www.sciencemag.org/news/2015/02/why-italian-earthquake-scientists-were-exonerated http://www.sciencemag.org/news/2015/02/why-italian-earthquak...
madaxe_again 8y ago
Reading that paper, it seems it solely comprises attaching sensors (I'd imagine piezo transducers bolted firmly onto measurement points, most likely) and listening - so it's hard to see how it could have had any effect, unless they attached the sensors with a method that would damage the bridge, which seems unlikely.
- lqet 8y ago
  Yes, I also just (slowly) realized this while skimming over the paper. So it is indeed completely passive.

by lqet 8y ago

hypertexthero 8y ago

You may want to get in touch with [Professor Raimondo Betti][1], who [I spoke][2] with at Columbia University prior to a talk he gave about his research on [a bridge cable corrosion monitoring system][3]. He was optimistic about the ability of his (from my understanding, passive) sensor system in helping prevent these tragedies, but pessimistic about the political will to apply it to bridges. [1]: http://civil.columbia.edu/raimondo-betti http://civil.columbia.edu/raimondo-betti [2]: https://www.simongriffee.com/notebook/GRS-20151015-100821/ https://www.simongriffee.com/notebook/GRS-20151015-100821/ [3]: https://www.youtube.com/watch?v=cP1CfGVVXO4 https://www.youtube.com/watch?v=cP1CfGVVXO4

lqet 8y ago
Many thanks! Just out of curiosity: why was he pessimistic about the political will to apply this method? Because politicians fear the results?
- hypertexthero 8y ago
  I am not sure, but that sounds right. This was a few years ago and my memory may be faulty, but I remember him saying that it would probably take the collapse of a large bridge like the Brooklyn or George Washington bridges in NYC before the authorities in the city would consider using the system.
- jandrese 8y ago
  From a political standpoint you are spending money that might tell you that you need to blow your budget on rebuilding some infrastructure right now. Bridge collapses are so rare that nobody thinks it will happen to them. Just ask the people of Minneapolis.

throwaway5752 8y ago

Be super careful with that line of thought: it is precisely what they will use to deflect blame from the construction, engineering, and maintenance issues. "The bridge wouldn't have failed if it weren't for that pesky diagnostic procedure that also happened to raise all sorts of problems about corrosion and structural integrity" edit: also - not an expert but interested and somewhat informed - this is a very common structural engineering technique and should under no circumstances, ever, lead to this kind of outcome on a sound structure.

SolarNet 8y ago
Also Italy has a (recent) history of prosecuting scientists who attempt to give their opinion (even if it isn't listened to). If I was an Italian scientist I would stay far away from predicting anything to or for the government. http://www.sciencemag.org/news/2015/02/why-italian-earthquake-scientists-were-exonerated http://www.sciencemag.org/news/2015/02/why-italian-earthquak...

madaxe_again 8y ago

Reading that paper, it seems it solely comprises attaching sensors (I'd imagine piezo transducers bolted firmly onto measurement points, most likely) and listening - so it's hard to see how it could have had any effect, unless they attached the sensors with a method that would damage the bridge, which seems unlikely.

lqet 8y ago
Yes, I also just (slowly) realized this while skimming over the paper. So it is indeed completely passive.