疲劳开裂结构等效分析谱构造方法

为了解决外场疲劳裂纹排故中结构疲劳载荷谱数据不全或过于复杂的问题,提出了一种适用于飞机外场疲劳开裂结构的等效分析谱构造方法。该方法以细节疲劳额定值(DFR)法和结构细节有限元分析为基础,构建地—空—地最大应力与结构疲劳寿命的变化曲线,进而通过寿命反推,获取适用的地—空—地损伤比,以此构建等效分析谱,谱型为等幅谱。通过应用实例,将该方法构造的载荷谱与实测谱进行了对比,确认了该方法的正确性和有效性。

Equivalent analysis spectrum construction method for ai rcraft structure containing cracks

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 ob-tained through fatigue life retroestimation.Finally,the equivalent analysis spectrum which is equiamplitude spectrum is con-structed.In an application example,the spectrum of using this method and the spectrum of the flight measurement are com-pared,and the following results can be obtained:this method is correct and effective.