Reply To: Nonlinear Fatigue Analysis

[danielshaw]

I do not know why your time step loading model is not producing valid results. 

You can use the time series load provider in an EN analysis even if the elastically calculated stresses exceed yield.  The time series load provider will use linear superpositon which is valid if the stresses are elastically calculated.  The EN engine will use an elastic-plastic correction (Hoffman-Seeger or Neuber) on the final stresses to calculate the plastic strains to be used in the fatigue evaluation.

You cannot use the time series load provider if plastic strains were calculated in the FE.  Linear superposition is not valid for nonlinear stress results.