关键词: 疲劳, 载荷谱, 地—空—地损伤比, 实测谱, 开裂结构

Abstract:

To solve the problem that the load spectrum data of the aircraft structure containing cracks are not complete or too complex, a load spectrum compiling method for the aircraft structure containing cracks is proposed,which is based on Detail Fatigue Rating (DFR) method and finite element analysis of structure details, and the change curve of maximum stress of ground-air-ground versus the structure fatigue life is built. Secondly, the applicable ground-air-ground damage ratio is obtained through fatigue life retroestimation. Finally, the equivalent analysis spectrum which is equiamplitude spectrum is constructed. In an application example, the spectrum of using this method and the spectrum of the flight measurement are compared, and the following results can be obtained:this method is correct and effective.

Key words: fatigue, load spectrum, ground-air-ground damage ratio, actual load spectrum, structure containing cracks