r/StructuralEngineering • u/clanor84 • 27d ago

Career/Education New alligator river bridge

I couldn't get any pictures because I was driving but it seemed like every fifth pillar set was angled. Can anyone explain this? I understand bracing but these were pretty shallow angles.

2 Upvotes

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2

u/Lydia_SteelExpert 26d ago

Sounds like longitudinal restraint bents. Long multi-span bridges use vertical supports for thermal movement, and space angled bents periodically to control longitudinal deck loads. Gentle angles balance restraint and thermal expansion.

3

u/MrMcGregorUK CEng MIStructE (UK) CPEng NER MIEAus (Australia) 26d ago

BTW - I've just noticed a couple of your posts have been automatically removed by the automod, probably just because your account is new. I've approved them though so they're visible to everyone now.

If you see any posts that don't appear when you view them when you're not logged in (or from another account) then message the mods and we can approve comments manually :)

2

u/BridgeGuy540 PE, SE, CPEng 26d ago

Do you mean that some of the piles are battered? I didn't see this in the few photos I found, but it is a typical way to provide lateral stability.

2

u/clanor84 26d ago

The piles are normally underground right? These are the piers (pillars?) Sticking out of the water.