非概率可靠性的拉伸载荷下飞机含孔复合材料安全性分析

针对拉伸载荷作用下飞机含孔复合材料易发生损伤失效的问题，为研究穿透型圆孔对复合材料安全性的影响，根据某型飞机实际使用的碳纤维复合材料，设计了无孔和含孔试样进行拉伸试验，获得宏观拉伸性能参数，对比分析穿透型圆孔对拉伸性能的影响；基于非概率可靠性分析方法，采用最小无穷范数指标，分别对训练强度提高前后的拉伸强度可靠性进行计算与分析，并总结了复合材料安全性分析方法。结果表明：穿透型圆孔会导致该复合材料拉伸强度的大幅下降，而对拉伸刚度影响不大，且拉伸强度下降率与孔径成正比；穿透型圆孔会引起该复合材料拉伸强度可靠性的大幅下降，下降程度随孔径的增大而增大；训练强度提高后，可靠性进一步下降，三种孔径的复合材料拉伸强度可靠性均降至1以下，严重影响复合材料安全性。

Study on the Safety of Aircraft Composite Materials Containing Holes under Tensile Loading Based on Non-Probabilistic Reliability

To address the problem that aircraft composite materials containing holes are prone to damage failure under tensile loading, in order to study the effect of penetrating circular holes on the safety of composite materials, tensile tests were designed for specimens without and with holes according to the actual carbon fiber composites used in a certain type of aircraft. The macroscopic tensile performance parameters were obtained, and the effects of penetrating round holes on the tensile performance were compared and analyzed. Based on the non probabilistic reliability analysis method, the reliability of tensile strength before and after the increase of training intensity was calculated and analyzed respectively by using the minimum infinite parametric index. And the safety analysis method of composite materials was summarized.The results show that the penetrating circular hole causes a significant decrease in the tensile strength of this composite, while it has little effect on the tensile stiffness. The rate of decrease in tensile strength is proportional to the hole diameter. The penetrating round holes causes a significant decrease in the tensile strength reliability of the composite, and the degree of decrease increases with the increase of the hole diameter. The reliability decreases further when the training strength is increased. The tensile strength reliability of the composites with all three pore diameters decreases to below 1, which seriously affects the safety of the composites.