飞机典型壁板结构剪切屈曲疲劳试验与分析方法  

Fatigue buckling test and analytical approach of aircraft typical panel structures

作　　者：苏少普[1] 常文魁[1] 陈先民[1] SU Shaopu;CHANG Wenkui;CHEN Xianmin(Metallic Structure Strength Department,Aircraft Strength Research Insitute of China,Xi'an 710065,China)

机构地区：[1]中国飞机强度研究所金属结构强度研究室,西安710065

出　　处：《航空学报》2022年第5期266-275,共10页Acta Aeronautica et Astronautica Sinica

基　　金：航空科学基金(2016 ZA23011)。

摘　　要：依据疲劳分析中的细节疲劳额定值法,提出了一种针对纯剪状态下飞机典型壁板结构的屈曲疲劳分析方法。采用整体垫板形式设计典型壁板试验件,避免“对角拉”方式施加剪切载荷时的非关键区破坏;建立剪切屈曲疲劳状态下细节疲劳额定值的分析模型,并给以试验验证;分析结构屈曲疲劳破坏模式,给出结构破坏及裂纹扩展特征,为结构抗屈曲疲劳设计提供技术支持。结果表明:屈曲疲劳的破坏多由于铆钉处受弯曲应力和剪切应力双重影响造成;起裂裂纹沿着垂直于屈曲波的方向扩展,当裂尖靠近屈曲波中心时,扩展速率急速增长;结构屈曲临界载荷随循环次数的增加而减少;提出的屈曲疲劳分析模型是合理可行的,这为结构后屈曲状态下的疲劳评估提供一种便利的工程算法。An efficient engineering method to evaluate fatigue buckling life of structure on pure shear is proposed based on detailed fatigue rate value.The typical panel test specimen applies a new design concept of integral inserted plate to avoid the failure of structure on non-critical zone in the process of diagonal tensile loading;Experimental results verify the feasibility of the proposed fatigue buckling model;The failure mechanism of structure on fatigue buckling and the correlated character of crack growth are analyzed to provide a technical support for aircraft anti-buckling design.This research illustrates that fatigue buckling failure is mostly ascribed to the effects of bending stress and shear stress on rivets.Once the structure is cracked,crack propagates along the vertical direction of buckling wave.When it arrives adjacent to the wave center,the growth rate excessively increases;the critical buckling load is decreasing with loading cycles increased.The proposed fatigue life evaluation method provides a convenient engineering algorithm for the fatigue evaluation of structure at post-buckling state.

关 键 词：屈曲疲劳 细节疲劳额定值 临界屈曲载荷 失效模式 裂纹扩展 

分 类 号：V215.6[航空宇航科学与技术—航空宇航推进理论与工程]