三明治复合材料加筋L型接头的弯曲承载能力和损伤机理

Bending load-bearing capacity and damage mechanism of composite sandwich L-joint with stiffeners

针对一种三明治复合材料加筋L型接头,介绍了其结构形式和成型工艺,通过试验测试了接头的弯曲承载能力,分析了接头的破坏模式,并对其损伤机理进行了研究,以探求接头的技术改进路径。研究结果表明:L型接头具有良好的吸能效果,在结构发生大变形破坏时,仍具有较高的弯曲承载能力;L型接头的破坏主要发生在垂横加强筋的相交处,初始损伤是相交处侧面的玻璃钢和芯材发生界面分离;工程上应将改进L型接头垂横加强筋相交处的蒙皮和芯材之间的连接工艺作为提高接头承载能力的技术路径。

Aiming at a sandwich composite L-joint with stiffeners,this paper presents its structure and molding process,analyzes the ways to damage the through testing its bending load-bearing capacity and researches the damage mechanism so as to seek after the technical improvement of L-joint.The results show that because of its good energy absorption properties,L-joint can maintain high loadbearing capacity when there is a large deformation in structure.The failure of L-joint occurs at the intersection between the horizontal stiffener and the vertical stiffener.The initial damage appears on the interface separation between skin and core on the side-face of the intersection.So improving the connection technology is an effective approach to increasing the load-bearing capacity of L-joint in engineering.