What are these thingies on suspension bridge cables?

  • Thread starter matthyaouw
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  • #1
matthyaouw
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Main Question or Discussion Point

Since I know there are a lot of engineer-types in these parts, maybe someone knows what these things are.

bridgee.jpg


Ther's a thing clamped high up on to the cable on the right, and every other cable on the bridge but I can't for the life of me work out what they are there for. any insight?
 

Answers and Replies

  • #2
Dembadon
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I haven't taken any engineering courses in my studies yet, but my guess is some sort of balance or stabilization mechanism? I'd imagine the cables could get pretty shifty in heavy winds, waves, etc. I'd guess that those "things" can be adjusted to take the wobble out of the cables?

Again, I'm no engineer; just throwin' it out there.
 
  • #3
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Those are Stockbridge dampers, a type of tuned mass damper. They're used to suppress vibrations in the cable and thus prevent structural damage and fatigue in the bridge. They're also used on some power lines and other cable-based structures.
 
  • #4
drizzle
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What's that red shadow for? A truck? Anyways, cool pic!

Oh for that thingy, I don't know but my guess would be to absorb vibrations caused by Earthquakes, if any by contacting those cables to a free ended solid material!


P.S. you beat me Vasara, damn it! I'm slow :grumpy:
 
  • #5
matthyaouw
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Those are Stockbridge dampers, a type of tuned mass damper. They're used to suppress vibrations in the cable and thus prevent structural damage and fatigue in the bridge. They're also used on some power lines and other cable-based structures.
Wonderful, thanks!
:smile:
 
  • #6
Evo
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Another great picture matthyaouw!
 
  • #7
Pyrrhus
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Those are nice marbles, we put on bridges to make them look neat :tongue2:
 
  • #8
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Love the photo, and I got to learn something new. Now how can I work "Stockbridge dampers" into a conversation?
 
  • #9
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Love the photo, and I got to learn something new. Now how can I work "Stockbridge dampers" into a conversation?
Agreed :biggrin:, I wouldn't bring them up in conversation though, it wont resonate well.
 
  • #10
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Agreed :biggrin:, I wouldn't bring them up in conversation though, it wont resonate well.
bahaha, that made me giggle. :rofl:
 
  • #11
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Very interesting:

The Stockbridge damper was invented in the 1920s by George H. Stockbridge, who was at the time working as an engineer for Southern California Edison. Stockbridge obtained US patent 1675391 on 3 July 1928 for a "vibration damper".[6] His patent described three means of damping vibrations on lines: a sack of metal punchings tied to the line; a short length of cable clamped parallel to the main cable; and a short (30 in, 75 cm) cable with a concrete mass fixed at each end.[6] It would be this last device that developed into the widely used Stockbridge damper.
http://en.wikipedia.org/wiki/Stockbridge_damper
 
  • #12
Moonbear
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Agreed :biggrin:, I wouldn't bring them up in conversation though, it wont resonate well.
:rofl: GROAN! (I've never been able to resist laughing at groaners. ...and since I've seen Danger back around...not THAT kind of groaner. :grumpy:)
 
  • #13
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Sorry, I didn't mean to string you all along.
 
  • #14
lisab
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What's that red shadow for?
Looks like matthyaouw is going to keep us in suspense.
 
  • #15
Danger
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...and since I've seen Danger back around...
Did I hear my name taken in vain?

it wont resonate well.
That was horribly good. It will echo in my mind for years...
 
  • #16
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Looks like matthyaouw is going to keep us in suspense.
HIyoooooooooo!!!
 
  • #17
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Wow, I learn something new every day(no surprise)
 
  • #18
matthyaouw
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Yeah Drizzle, it's a truck. Sorry to keep you hanging around!
I feel bad that's the best I could come up with...

Glad people like the photo :smile:
 
  • #19
brewnog
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Humber?

Last time I went, I walked the length of it. It was a windy day and you could see the expansion joints taking out a couple of inches every few seconds.

It's been my profile picture for ages!
 
  • #20
matthyaouw
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Humber?

Last time I went, I walked the length of it. It was a windy day and you could see the expansion joints taking out a couple of inches every few seconds.

It's been my profile picture for ages!
I love standing with one foot either side of the joint. It's a really unusual feeling :biggrin:
Magnificent piece of construction it is. Seeing it so often there's times I hardly notice it but every now and then I just think 'holy crap, that's amazing'
 

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