Torsional Moments in curved bridge

[Imran Structural Engineer]

How are torsional moments in curved box girder bridge calculated. Can someone provide literature ? I'm doing analysis on software but I want to calculate them manually. I've used equations from pci and aisc manual but answers do not match with software.
Also, for a bridge with sharp curvature(60m/197ft), what stability checks are usually required.
Thank you

 

[Lomarandil]

I don't recall whether it specifically addressed box girders, but highly recommend NCHRP 725 as a starting point:

https://www.trb.org/Publications/Blurbs/167646.aspx

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just call me Lo.

 

[Imran Structural Engineer]

Thank you