Hello,
I am currently working on a unique steel plate design to be used for a very minor lane widening on a bridge. This steel plate design is not an orthotropic steel bridge deck design.
However, AASHTO LRFD Bridge Specifications suggests for unique components and details that a refined analysis be used (but this complicates determination of force effects).
The model I have created is a Finite Element Model with fine plate element meshing around areas of concern (i.e. where plates and stiffeners meet).
I am currently doing a fatigue analysis due to live loads on the model, however I am having trouble understanding which stress outputs I should be using to calculate the fatigue stress range on my plate elements.
STAAD.Pro offers numerous stress type outputs: Max Absolute, Tresca, Von Mis, Membrane Stress (on local axises), Bending Stresses, and Shear Stresses (both in plane and out of plane).
Currently, based on the nominal stress approach, I am using the combined stress effects (membrane plus bending about local axises) to calculate the fatigue stress ranges. However, I wanted to make sure this was correct or if STAAD had a better way of determining fatigue evaluation.
Additionally, does STAAD.Pro treat connections between plates that are at an angle as welded joints? If so, does STAAD apply a stress concentration effect?
Thank you for your assistance.