侧边约束对复合材料加筋板屈曲及后屈曲特性的影响

Effect of side boundary constraint on buckling and post- buckling behaviors of composite stiffened panels

对侧边受到简支约束和固支约束的复合材料工型加筋板进行轴压试验和数值模拟,研究侧边约束对加筋板屈曲及后屈曲特性的影响,并进一步探讨分析结构破坏机理。轴压试验中使用影像云纹实时监测加筋板失稳模态,数值模拟基于ABAQUS使用Hashin层内失效准则和界面单元模拟脱粘建立有限元模型。计算结果与试验结果相吻合。研究表明不同侧边约束下加筋板具有相似的失稳模态和破坏模式,尽管侧边固支加筋板失稳载荷高于侧边简支加筋板,但其承载能力并无明显提高;加筋板结构承载主要由筋条决定,而筋条蒙皮大面积脱粘发生在结构失效之后。

Axial compression test and numerical simulation are conducted on the composite stiffened panels with simply supported and clamped sides to study the effect of side constraint on panels＇ buckling and postbuckling behaviors,and then the damage mechanism of panels are further discussed and analyzed. M oiré interferometry is used to monitor the buckling mode in the test. A finite element model is developed using the software of ABAQUS by means of Hashin intralaminar failure criteria and cohesive element to simulate debond. The calculated values are in conformity with the test values. The study indicates that the composite stiffened panelsunder different side constraints have similar buckling models and collapse patterns. Although the collapsing load of the composite stiffened panels with clamped side is higher than that of the composite stiffened panels with simply supported side,the ultimate load of the formerhas not significantlyincreased. The capacity of stiffened panels is determined by the stiffener,and the cohesion between stiffener and skin debonds rapidly after collapse.