Simulation of Operational Loading Spectrum and its Effect on Fatigue Crack Growth

The paper presents analyses of crack growth rates for two different types of load sequences. The first one was the measured natural sequence of operational loads and the second one was evaluated as a blocked sequence with the same loading spectrum. Specimens from 2124-T851 aluminum alloy were made and tested. Numerical simulations of the performed tests were made using the FASTRAN retardation model implemented in the AFGROW software and the effect of the type of loading sequence was identified.