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本文研究了一种谱载荷作用下的短裂纹扩展规律，并对谱载荷下的疲劳损伤进行了预测与分析。实验发现：谱载荷下的单边穿透短裂纹和缺口短裂纹都能够在长裂纹的门槛值以下以较高的速率扩展，表现出与常幅下短裂纹相似的扩展规律．但谱载荷下的短裂纹扩展速率略低于常幅下的短裂纹扩展速率，谱载荷下长裂纹的扩展速率远低于常幅下长裂纹的扩展速率．利用特征值方法和常幅疲劳实验预测了冰载荷谱下的疲劳损伤，提出了预测冰载荷谱下的疲劳损伤较为合理的方法。
In this paper, we study the propagation of short cracks under the action of spectral loading, and predict and analyze the fatigue damage under spectral loading. The experimental results show that both short-edge crack and short crack notch under the spectral loading can propagate at a higher rate below the threshold value of long crack, and show a similar propagation law as the short crack under normal amplitude. However, the short crack propagation rate under the spectral loading is slightly lower than that of the short crack propagation under the normal amplitude. The propagation rate of the long crack under the spectral loading is much lower than the growth rate of the long crack under the normal amplitude. The eigenvalue method and fatigue test were used to predict the fatigue damage under ice load spectrum. A reasonable method to predict the fatigue damage under ice load spectrum was proposed.