Bridge failure near Albany NY 15

[bridgebuster]

I think they forgot some stiffeners

Link

 

[JohnRBaker]

Are you sure that that's the correct link? While it goes to an item about a bridge, it's only talking about replacing an existing bridge. Besides, the item is nearly five months old.

John R. Baker, P.E. (ret)
Irvine, CA
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It's finding someone you can't live without

 

[IRstuff]

https://www.timesunion.com/news/article/construction-albany-county-rail-trail-bridge-18197215.php

Looks like the wooden prop was no match for all the concrete

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[WinelandV]

Such an odd bridge: continuous bottom flange, and varying top flange height with the middle section being taller. Moment demand wise, this makes sense, but that is a rather abrupt transition from the shallower section to the deeper section.

Please note that is a "v" (as in Violin) not a "y".

 

[SWComposites]

Oh my, what a horrible design detail.
My guess - some genius analyzed it with an FEM and only checked strength; never checked buckling. Have seen that too many times before.

 

[Lomarandil]

Wineland -- the story told elsewhere was that the newly fabricated single span bridge was meant to visually imitate the historic railroad bridge, which was three spans with a deeper and longer middle span.

 

[bridgebuster]

try this one

Link

 

[WinelandV]

Ah, that makes sense. Thanks Lo!

Please note that is a "v" (as in Violin) not a "y".

 

[JohnRBaker]

the story told elsewhere was that the newly fabricated single span bridge was meant to visually imitate the historic railroad bridge, which was three spans with a deeper and longer middle span.

You might be right as this image is from that original link that bridgebuster posted:

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[azcats]

Even the non-buckled side looks like it's partially buckled (unless my eyes are playing tricks).

 

[EdStainless]

They forgot to take the deep section to the support.
Well they get to try again.

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P.E. Metallurgy, consulting work welcomed

 

[LittleInch]

I bet the old one wasn't filled with concrete....

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[SnTMan]

Pedestrian bridge, won't support its own deck

The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[waross]

FIGG?

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[3DDave]

Sure. Blame the bridge for failing. This failure clearly occurred somewhere else.

 

[LittleInch]

Looks to me like they just copied the old one. On the basis that it has survived 100 yrs maybe no one did any calculations??

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[TugboatEng]

Are the bridge beams asymmetrical due to the angled crossing? If so, it appears as if they put the bridge up 180° out. That explains why the support was so far from the taller beam section.

 

[bridgebuster]

sad to say but this is the second time the designer lost a ped bridge.

 

[Murph 9000]

Looks to me like they just copied the old one. On the basis that it has survived 100 yrs maybe no one did any calculations??

Look closer. They very roughly copied the aesthetic, but did not copy the engineering design of the old bridge. There's a big difference in design where the beam steps down.

 

[TugboatEng]

There is also a big difference in design where the beam steps down between the two ends of the collapsed bridge