后屈曲复合材料加筋壁板的破坏预测方法

Prediction and Damage Analysis of the Postbuckling for Stiffened Composite Panel

建立了复合材料加筋壁板屈曲和后屈曲有限元分析模型。该模型采用实体单元有效模拟筋条和蒙皮之间的连接。连接界面采用二次应力准则作为损伤起始判据、混合能量准则作为损伤扩展判据,并自定义损伤变量实现刚度非线性衰减。复合材料壁板采用断裂面准则作为失效判据,该判据能有效判断基体的失效。基于ABAQUS动态显示分析步,模拟了复合材料加筋壁板在压缩载荷下屈曲和后屈曲的过程,有限元分析结果与试验数据对比良好,证明了该方法的有效性。

A strength analysis model based on ‘dynamic,explicit＇step in ABAQUS was presented to study buckling and post-buckling behavior of integral stiffened composite panel subjected to compressive loading.In this model,the debonding failure between the skin and stiffener was considered by adding self-defined solid elements.Quads failure criteria and act plane failure criteria was used to identify the onset of damage events of the interface elements and composite,respectively.A self-defined nonlinear degradation rule was presented to simulate the propagation of the interface elements.Based on ABAQUS,a material degradation rule of composite was presented.The process of damage initiation,propagation and failure of the stiffened composite panels was simulated in detail.At last,a good agreement between tests and numerical prediction was observed.