民机复合材料结构冲击后压缩设计值的确定方法

冲击后压缩设计许用值是复合材料飞机结构设计的一个非常重要的参数。本文通过分析常用的目视检测方法和飞机结构冲击能量统计结果,从凹坑深度和冲击能量截止值两方面定义了目视勉强可见损伤;根据民机设计兼顾安全性和经济性的特点,作者提出压缩设计许用值中的目视勉强可见损伤应综合考虑,慎重确定。文章还研究了复合材料层压板的抗冲击性能,从工程应用角度给出了结构冲击后压缩设计许用值的确定要点,即用小试样的冲击后压缩试验结果推导的基准系数和环境系数,对元件乃至典型结构件的冲击后压缩试验结果进行修正。

Determination Method for Civil Aircraft Composite Structure Compression after Impact Design Value

Design allowable of compression after impact (CAI) is an important parameter for design of aircraft structure made of composite material. In this paper, by analyzing the conventional visual inspection method and aircraft structural impact energy statistical results, barely visible impact damage (BVID) is defined based on both dent depth and impact energy cut-off value. According to both safety and economy features of civil aircraft design, authors proposed that BVID in design allowable of compression after impact should be comprehensively considered and carefully determined. Moreover, the study of impact resistance of composite laminates was also carried out, and the key points of determining structure design allowable of compression after impact were provided from engineering application viewpoint. Specifically, experimental results of compression after impact of civil aircraft component even typical structure are revised by using reference coefficient and environmental factor derived from small specimen experimental results of compression after impact.