Elasto-plastic Response of Composite Structures under the Impact Loading by Spline Element Method

基于剪切变形理论，采用样条元方法对纤维复合材料层合板和圆柱壳板的振动和弹塑性动力响应进行了分析。研究了层序、层数和几何参数对复合材料层合结构破坏模式和破坏扩展的影响。1)复合材料层合板与柱状板的振动特性本文提出了基于高阶剪切变形理论的样条法半解析模型，用于分析纤维复合材料层合板与柱状板的振动。研究了层板厚度比、模量比和叠层顺序对交叉层和角层复合板壳频率的影响。通过选择叠层顺序和纤维取向角，使复合材料结构具有较高的柔韧性。2)冲击载荷作用下复合材料层合板和柱状板的弹塑性响应采用等参退化单元和von Mises屈服准则结合Prandtl-Reuss流动规律研究了纤维复合材料层合板和柱状板在冲击载荷作用下的动力破坏。研究了厚度比、层合角度、层合顺序和边界条件对动态变形和屈服区在厚度和各层间扩展的影响。观察到不同的厚度比和层状结构导致的不同的破坏模式和破坏扩展。

In this study, vibration and elasto-plastic dynamic responses of fiber-composite laminated plates and cylindrical shell panels were analyzed by the spline element methods based on the shear deformation theories. The effects of lamina sequence, the number of lamina and geometrical parameters on the failure modes and the propagation of failure of the omposite laminated structures.1) Vibrating Characteristics of Composite Laminated Plates and Cylindrical PanelsThe spline strip method which is a semi-analytical model based on the higher-order shear defotmation theory is presented to analyze vibration of fiber-composite laminated plates and cylindrical panels. The effect of thickness ratio, moduli ratio and stacking sequence of lamina on the frequencies of cross-ply and angle-ply laminated plates and shells were investigated. High flexibility of composite structures has been obtained by selecting the stacking sequance of lamina and fiber-oriantation angle.2) Elasto-plastic Response of Composite Laminated Plates and Cylindrical Panels due to Impact LoadingDynamic failure of fiber-composite laminated plates and cylindrical planels under the action of impact load by using an isoparametric degenerated element and the von Mises yield criterion combined with the Prandtl-Reuss flow rule. The effects of thickness ratio, angle of lamination, stacking sequence of lamina and boundary condition on the dynamic deformations and the propagation of yield region through thickness and each lamina are investigated. It is seen that the different failure modes and failure propagation due to the thickness ratio and lamina structure have been observed.