This is a study on the loading spectrum for full-scale fatigue testing of composite aircraft structures. Fatigue tests are performed to confirm the durability and damage tolerance of a composite aircraft structure. In particular, as composite materials have fatigue life variance larger than that of metallic materials, it takes a considerable amount of time to complete the aforementioned tests. Investigation of key factors such as spectrum truncation and load enhancement is required to create a load spectrum that can reasonably shorten the test time. In other words, criteria for removing the loads that have little effect on the fatigue life and applying factors for the severe load spectrum should be studied to produce the optimal load spectrum, which depends on the fatigue characteristics of the composite material. In this study, coupon tests and statistical analyses of carbon fiber/epoxy composites were performed to analyze the key elements and establish the criteria for the reliable truncation level and load factor for an optimal loading spectrum.

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复合飞机全尺寸疲劳试验疲劳载荷谱的建立介绍

这是一项关于复合材料飞机结构全尺寸疲劳试验载荷谱的研究。进行疲劳测试以确认复合材料飞机结构的耐久性和损伤容限。尤其是复合材料的疲劳寿命方差比金属材料大，完成上述试验需要相当长的时间。需要对频谱截断和负载增强等关键因素进行研究，以创建可以合理缩短测试时间的负载频谱。换句话说，应研究去除对疲劳寿命影响很小的载荷的标准和适用于严重载荷谱的因素，以产生最佳载荷谱，这取决于复合材料的疲劳特性。在这项研究中，