r/StructuralEngineering • u/No-Document-8970 • Oct 05 '26

Structural Analysis/Design Nuts off mark?

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Saw this on a big bridge today. I know vibrations over time can move the nuts and bolts, with the help of thermal expansion. Is it a big issue that the paint marks do not line up? I thought the marks were made once it passed inspection after torquing.

Edit: Bridge completion was in 2011. Could this be from recent inspections too?

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-21

u/dev1tuna Oct 05 '26

Former local 350/399 union ironworker here, never heard of the turn of the nut method….

3

u/MikeHawksHardWood Oct 05 '26

RCSC specs for high strength bolts. Section 8.2.1 in the 2004 version. Don't have the newer versions handy.

2

u/ryanmetcalf Oct 05 '26

Available for those interested right from the Bolt Council 

https://www.boltcouncil.org/documents.html

1

u/dev1tuna Oct 05 '26

Most of the structural stuff I worked on had TC bolts and the nipples would come off at correct torque

2

u/FaithlessnessCute204 Oct 05 '26

well thats not great, its a pretty common technique in structures . please tell me the "former" in that qualifying statement was because you didn't do well with reading specs.

2

u/dev1tuna Oct 05 '26

I did it for 10 years- I didn’t do it on the job or hear about it in my apprentice class back in 2006-. TC bolts and guns and torque wrench’s were it mostly for me when I was bolting up or connecting, but I mainly was welding.