压缩载荷下复合材料整体加筋板渐进损伤非线性数值分析

Nonlinear progressive damage analysis of integral stiffened composite panels under compressive load

建立了考虑脱粘的复合材料整体加筋板渐进损伤有限元分析模型。该模型采用界面单元模拟筋条与壁板之间的连接界面,连接界面和复合材料层板分别采用Quads准则和Hashin准则作为失效判据,基于ABAQUS软件,建立了含连续损伤状态变量的材料刚度退化方案。基于该模型,采用非线性有限元方法研究了压缩载荷下复合材料整体加筋壁板在考虑初始几何缺陷时的破坏过程,分析了结构相应失效模式的细观损伤机制;详细讨论了轴向刚度比对结构承载能力及破坏模式的影响。结果表明:考虑脱粘损伤的有限元模型能有效模拟加筋板的破坏过程;在加筋板铺层设计合理的情况下,增加筋条与壁板刚度比能有效提高加筋板截面单位面积的承载能力。

A strength analysis model was presented to study the progressive damage of integral stiffened composite panels subjected to compressive loading by using the nonlinear finite element method.In the model,the debonding failure of the adhesive between the skin and stiffener was considered by adding cohesive elements between the shell elements.Quads failure criteria and Hashin＇s failure criteria were adopted to identify the occurring of damage events of the cohesive elements and the composite panels,respectively.Based on ABAQUS,a material degradation rule containing continuum damage status variables was presented.The process of damage initiation,propagation and catastrophic failure of the integral stiffened composite panels was simulated in detail by the proposed model,and the initial geometric imperfection was taken into account.Axial stiffness ratio of stiffener and skin was defined and conducted to study the effects to the structure on the carrying capacity and failure modes.The results indicate that： the model can predict the damage process of integral stiffened panel effectively;under the condition the ply design is reasonable,increasing the stiffness ratio can to some extent improve the unit area bearing capacity of the cross section of stiffened composite panels.