复合材料加筋壁板界面损伤扩展机理研究

Mechanism of Interfacial Damage Propagation of Composite Stiffened Panels

复合材料加筋壁板筋条-蒙皮界面损伤研究中Ⅲ型断裂能的作用往往被忽略,本文结合物理试验和数值方法对复合材料开剖面工形加筋壁板和闭剖面帽形加筋壁板开展了后屈曲筋条-蒙皮界面损伤扩展研究。利用考虑法向压缩抑制界面剪切失效机制的新形界面损伤起始准则和考虑Ⅲ型断裂的Reeder界面损伤扩展准则对两种构形加筋壁板后屈曲历程进行数值模拟分析,对比两种构形壁板的屈曲模式、破坏形式以及筋条-蒙皮界面损伤扩展时的各形能量释放率的分布情况。得出闭剖面帽形加筋壁板筋条-蒙皮界面主要在面外剥离力的作用下损伤扩展,I型断裂能在界面的损伤起始和扩展中起主要作用;开面工形加筋壁板界面主要在剪力的作用下损伤扩展,Ⅲ型断裂能在损伤横向扩展中起主导作用。上述研究阐述了各型断裂能在复合材料加筋壁板界面损伤扩展过程中的作用机理,为复合材料加筋壁板后屈曲数值模拟分析方法研究奠定基础。

The significance of Type II fracture energy in influencing damage to the stiffener-skin interface of composite stiff-ened panels is often disregarded.In this paper,the stiffener-skin interface damage propagation for buckled I-shaped and 2-shaped stiffened composite panels was studied by experimental and numerical methods.The post-buckling process of two kinds of stiffened panels was analyzed by numerical simulation based on the initial criterion and the Reeder interface damage propagation criterion considering II fracture.The buckling modes and failure forms of two types of panels were compared,and the distributions of energy release rates of each type during stiffener-skin interface damage propagation were character-ized.It is concluded that for 2-shaped stiffened composite panels.the damage propagation of interface is mainly caused by out-plane peeling force,and the type I fracture energy plays a major role in the damage initiation and propagation of the interface.for l-shaped stiffened composite panels,the damage propagation of interface is mainly caused by shear force,and the type II fracture energy plays a dominant role in the damage propagation of the interface.The above-mentioned study e-lucidates the mechanisms by which various types of fracture energies operate during the process of interfacial damage propa-gation in composite stifened panels.This establishes a foundation for the investigation of numerical simulation analysis meth-ods for the post-buckling behavior of composite stiffened panels.