关键词: 重谱, 基准谱, 疲劳试验寿命, 疲劳分散系数, 疲劳损伤

Abstract:

Based on research on the relationship between test stress and distribution of fatigue scatter factor, this paper concludes that heavy spectra with high damage under operational loads may reduce the life but not the fatigue scatter factor. This conclusion contradicts with the Aircraft Structural Strength Specifications published in China in 2010, which states that a fatigue scatter factor of half that for the mean spectra can be selected for heavy spectra (i.e. 2 instead of 4). To verify the conclusion of this paper, test data of heavy spectra and mean spectra under operational loads with 5 simulated items of different materials and structures are found and used and they all bear witness to its correctness.

Key words: heavy spectrum, baseline spectrum, fatigue test life, fatigue scatter factor, fatigue damage