针对薄板构件振动疲劳损伤问题,提出基于模态应变能结构损伤识别新方法。该方法以结构损伤会导致其模态性能变化为依据,通过比较弹性薄板结构单元损伤前后的模态应变能变化率构造损伤指针。在构建损伤指针之前,假定弹性板的刚度是由单元刚度组成,在定义单元刚度灵敏度公式基础上建立弹性薄板损伤前后模态应变能变化关系。最后,基于模态柔度曲率法验证模态应变能法在弹性薄板单损伤与多损伤识别方面的优劣性。
A novel method for structural fatigue damage identification of aircraft thin plates based on modal strainenergy analysis is proposed. Since structural damage can lead to the variation of modal performance, the modal strainenergies of the thin plate before and after the damage are compared and the variation rate of the modal strain energy ischosen as the damage indicator. Before the damage indicator construction, the stiffness of the elastic plate is composed ofelement stiffness. Based on the definition of sensitivity formula of elemental stiffness, the relation of modal strain energy ofthe thin plate before and after the damaged is set up. The examples are given. Finally, the present method is compared withthe MFC method, their advantage and disadvantage in single damage and multiple damage identification are discussed.