Comparative research on the accumulative damage rules under multiaxial block loading spectrum for 2024-T4 aluminum alloy

Different multiaxial multi-block loading and random block loading spectra were used to conduct variable amplitude fatigue tests on 2024-T4 aluminum alloy. These spectra were derived from 16 kinds of constant amplitude multiaxial loadings. Five accumulative damage models were introduced and the critical damages given by these models were compared with the experimental results. It is demonstrated that Palmgren–Miner-Law and Shamsaei’s approach both led to good coincidences with the experimental results, Manson’s damage curve approach (DCA) and Morrow’s rule were not suitable for both multiaxial multi-block loading and random block loading spectra, while Carpinteri’s model was inapplicable to 2024-T4 aluminum alloy.