薄蜂窝复合材料夹芯结构侧压性能研究

Study of Thin-core Honeycomb Sandwich Composite Structures' Behavior Under Edgewise Compression

对不同构型薄蜂窝复合材料夹芯结构侧向压缩响应进行了试验研究,研究参数包括芯材高度、芯材密度和面板刚度。结果表明,蜂窝芯材高度严重影响蜂窝结构失稳载荷和峰值载荷,而上下面板的刚度不对称性会严重降低失稳载荷却对峰值载荷影响不大。薄蜂窝复合材料夹芯结构的整体破坏过程与芯材密度、芯材高度均有关系,而受刚度不对称性影响不大。薄蜂窝复合材料夹芯结构在侧向压缩载荷下的主要失效模式是蜂窝芯材剪切破坏,通过高速摄像机对蜂窝局部进行观察,发现失效起始于单个蜂格的剪切破坏,导致其高度降低,继而引起上下两侧蜂格破坏,并且迅速扩展到上下约3个蜂格,导致载荷突降。若继续加载,破坏继续向两侧蜂格扩展,且载荷基本不变。

Edgewise compressed responses for different configurations of thin-core honeycomb sandwich composite structures were studied. Core＇s thickness,core＇s density and the symmetry of panel stiffness have different effects. The thickness of core seriously affects the buckling load and peak load of the structures,while the asymmetry of the upper and lower panels＇ stiffness simply severely reduce the buckling load. The overall damage process of thin honeycomb sandwich composite structures is influenced by core＇s density and core＇s thickness,but not affected by the asymmetry of the stiffness. Cellular core shear failure is the main failure mode for the thin-core honeycomb sandwich composite structure under edgewise compression. By high-speed cameras to observe the cellular local,the failure of the structure start at the shear failure of a single cell,leading to its reduced height,which in turn causes cell damage of both sides. And quickly spread to about three cells of the upper and the lower,resulting in a load dump. If continues to load,the damage of cell continues to expand to both sides of the original damaged region,while the load almost unchanged.