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United States

Golden Gate Bridge Starts To 'Sing' After Design Fix (theguardian.com) 50

San Francisco's famous Golden Gate Bridge has started "singing" following recent changes to bicycle-path railings that appear to make music as the wind blows through them, residents have reported. The Guardian reports: Paolo Cosulich-Schwartz, a Golden Gate Bridge, Highway & Transportation District spokesperson, said the sounds stemmed from long-planned wind retrofitting. "The new musical tones coming from the bridge are a known and inevitable phenomenon that stem from our wind retrofit project during very high winds. The wind retrofit project is designed to make the Bridge more aerodynamic under high wind conditions and is necessary to ensure the safety and structural integrity of the Bridge for generations to come," Cosulich-Schwartz said.

"We knew going into the handrail replacement that the bridge would sing during exceptionally high winds from the west, as we saw yesterday. We are pleased to see the new railing is allowing wind to flow more smoothly across the bridge." Others who posted videos of the novel sound appeared more at ease, however. One described it as "so peaceful." Another said: "So crazy but also kinda beautiful!!" "We can hear this in our house more than three miles away from the bridge. It's crazy making," one user wrote Friday evening.

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Golden Gate Bridge Starts To 'Sing' After Design Fix

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  • SInging may be ok (Score:4, Insightful)

    by ISoldat53 ( 977164 ) on Monday June 08, 2020 @06:44PM (#60161736)
    as long as it doesn't start dancing.
  • Dark AF (Score:5, Funny)

    by GameboyRMH ( 1153867 ) <<moc.liamg> <ta> <hmryobemag>> on Monday June 08, 2020 @06:53PM (#60161760) Journal

    The world's biggest suicide machine now emits eerie wailing sounds? Damn.

  • by divide overflow ( 599608 ) on Monday June 08, 2020 @07:01PM (#60161784)
    Symphony for Bridge and Wind in A major.
  • "Singing" (Score:5, Funny)

    by alvinrod ( 889928 ) on Monday June 08, 2020 @07:12PM (#60161820)
    From the summary:

    "We can hear this in our house more than three miles away from the bridge. It's crazy making," one user wrote Friday evening.

    Hats off to the clever bastard that managed to convince everyone that the noise pollution is "singing". I know this is in San Francisco, but that sounds like something out of Madison Avenue.

    • That would drive me batshit. I had to buy a white noise generator a couple years ago because some maniac near me installed a wind chime.
      • by narcc ( 412956 )

        I've never heard an unpleasant wind chime. Crickets, cicadas, and birds must drive you crazy. I'm so sorry.

        • Some people can appreciate silence. Some others are psychos.
        • Err... *most* wind chimes are unpleasantly atonal. It is possible to purchase tonal windchimes and they are quite pleasant. (I have a set that are tuned I-II-III-V-VIII).

          Also, to the GP: did you live 3' from your maniac neighbor's windchimes? I have mine hung on the back of my house and between the house insulation and the distance to my neighbors (30 feet) they are essentially silent indoors. Hell, they are on my house and they are nearly silent in *my* house. And my windchimes are loud.

          • by cusco ( 717999 )

            An older house or apartment with single pane aluminum framed windows will pass pretty much every sound unimpeded. Before we replaced ours you could quite literally understand people having conversations on the sidewalk 20 feet away with the windows closed.

        • When you mess with a wind chime indoors in a store, they are pleasant, peaceful musical instruments, (my theory is this is due to human physiology causing them to move in a more rhythmic circular patten when you hold one) Were I live, if you hang one outdoors, it sounds like someone dumped a silverware drawer into a metal barrel and hurled it down a flight of stairs.
          • if you hang one outdoors, it sounds like someone dumped a silverware drawer into a metal barrel and hurled it down a flight of stairs.

            Exactly this.

  • by edi_guy ( 2225738 ) on Monday June 08, 2020 @07:22PM (#60161844)

    I wonder if the new, more aerodynamic railings were required because of the suicide barriers/nets being installed?(https://sf.curbed.com/2019/12/13/21020600/golden-gate-bridge-suicide-barrier-delayed-2023) . Increased windage due to the barriers means needing to reduce it elsewhere.

  • by ellbee ( 93668 ) on Monday June 08, 2020 @08:00PM (#60161936)

    From what I've read this was needed because the old railings had so much resistance the bridge became unsafe when the wind reach ~68mph. The new railings are thinner allowing more airflow which raises the safety margin up to 100mph. The new design necessary because they've observed over the past decade that storms have been getting stronger which is attributed to changing climate.

  • We can hear this in our house more than three miles away from the bridge. It's crazy making

    Lawsuit in 5...4...3...2...

  • You can tune a piano but you can't tune a bridge. I mean fish.
  • Noise pollution? (Score:5, Interesting)

    by acoustix ( 123925 ) on Monday June 08, 2020 @08:57PM (#60162112)

    Wouldn't this qualify as noise pollution? I mean, if this wasn't something that was naturally occurring and then this man made structure started making a noise that can be heard miles away then I can see people getting upset. Just like an airport, racetrack, etc.

    I'm 1,800 miles away so I really don't care. But it will be interesting to see if there's a big fuss made.

  • by AlanObject ( 3603453 ) on Monday June 08, 2020 @09:01PM (#60162122)

    I know nothing about this so that is why I am asking.

    Isn't the sound the result of turbulence? If the retrofit is causing turbulence that wasn't there before how is that desirable from an aerodynamic point of view? I would think you would want, as much as possible, a smooth laminar flow which would eliminate drag wherever it can.

    Any aeronautical engineers in the house?

    • by Pascoea ( 968200 )

      Any aeronautical engineers in the house?

      Would you settle for an armchair expert? We have lots of those.

      I do remember an article from Popular Science, back when it was useful, suggesting that skin turbulence can reduce drag. Hopefully this [google.com] link works. "Bumps to the rescue" Popular Science, July 1998. Possibly the same theory here?

      • Any aeronautical engineers in the house?

        Would you settle for an armchair expert? We have lots of those.

        I do remember an article from Popular Science, back when it was useful, suggesting that skin turbulence can reduce drag. Hopefully this [google.com] link works. "Bumps to the rescue" Popular Science, July 1998. Possibly the same theory here?

        That's the same principle for putting dimples on golf balls. Small holes actually reduce drag and allow the ball to travel farther. Also seen in efficiency of driving a pickup truck with the tailgate up instead of down.

        • by BranMan ( 29917 )

          Plus the Mythbusters dimpled a car like a golf ball and improved fuel efficiency for it - again by reducing drag. I don't remember exactly, but I think it was single digits improvement (like 5%).

    • Re:Turbulence? (Score:4, Informative)

      by hankwang ( 413283 ) on Monday June 08, 2020 @10:58PM (#60162376) Homepage

      Turbulence is by definition chaotic and would result in white or pink noise. What you hear is likely Karman vortex shedding, which happens when a cylindrical object is placed perpendicular to a fluid flow. The frequency is approximately f=v/(5d) for velocity v and diameter d. If the wind speed was 25 m/s and the frequency 150 Hz, that would be consistent with a diameter of 3 cm. A big flat plate would generate more drag, but without the singing.

      The drag would be even lower with a wing profile rather than a cylinder, but you probably don't want sharp edges on a safety railing.

      https://en.wikipedia.org/wiki/... [wikipedia.org]

      • No, no its not
        google 'karman vortex'

        However I suspect this is due to pipe ends not being capped.

        • No, no its not
          google 'karman vortex'

          What are you trying to tell me with your reply? What "is not"? I linked to the wikipedia article on Karman vortex streets.

          Did you intend to reply to a different comment?

      • Turbulence is by definition chaotic

        It definitely is not. Turbulence by definition is nothing more than extreme or unsteady movement of a fluid. The Karman vortex street is by definition a form of turbulence. In many cases "turbulence" is mathematically predictable to an insane precision with only micro fine examples of it being chaotic (kind of like how wind is chaotic outside your house, but completely predictable on a national scale when calculating air pressure zones).

    • Isn't the sound the result of turbulence? If the retrofit is causing turbulence that wasn't there before how is that desirable from an aerodynamic point of view?

      Turbulence and aerodynamics are related. If you want to really get into this rabbit hole then I suggest starting by researching the dimples in a golfball and how they affect the ball's trajectory.

  • ... for very large approximations of singing. Wind blowing through the eucalyptus groves and casuarina groves along the East Coast Road in South India "sing" a lot better than this. That eeriee "ooooooo .... oooo... " sound is stock in trade for the background music for almost all the scary movies there.
  • You sure it's not going to collapse soon?

The unfacts, did we have them, are too imprecisely few to warrant our certitude.

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