Louie:
I assume that you are using the Mechanical Fatigue Tool (FT) with time history loading (non-constant amplitude, proportional loading). If so, the FT outputs life in repeats of the loading cycle. For example, if your loading cycle represents 1 hour of operation then reported life is repeats of 1 hour of operation.
The FT internally uses rainflow counting to organize the stresses into “bins or blocks” of data that represent stress ranges and mean stresses. You can block the rainflow matrix, but the FT will not report the fatigue damage per bin.
If you have the time history loading, you should not need to use a random vibration approach.
Dan
You are navigating away from the AIS Discovery experience