受压脱层层板的有限元分析

受压复合材料脱层层合板的局部屈曲,在脱层尖端引起很大的应力集中,导致脱层扩展而发生破坏。本文利用一阶剪切的直线层板理论和折线层板理论,建立了一维受压脱层层合板的分析模型,进而根据虚裂纹闭合技术,得出了脱层尖端能量释放率各型分量G_Ⅰ,G_Ⅱ,G_Ⅲ的一维有限元计算表达式,并且验证了该方法的正确性。通过数值计算,讨论了外载、脱层长度和层板纤维铺层方向对能量释放率的影响。结果表明,脱层的扩展取决G_Ⅰ和G_Ⅱ,而C_Ⅲ的影响可以忽略不计。对于外载较大时发生的脱层扩展,很可能诱发层板的整体失稳,脱层的扩展将变成破坏性的快速扩展。

Finite Element Analysis of Delaminated Laminates under Compression

Local buckling of delaminated laminates subjected to compressive loads creates high-concentrated interlaminar stress near the delamination front. This often causes delamina-tion growth and leads the structure to failure. In this paper.a one-dimensional modelling of delaminated laminates under compression are developed based on the first order shear de-formable plate theory. The components of energy release rate are calculated using a geo-metrically nonlinear,one-dimensional finite element analysis. The checks of the analysis are discussed. In the parametric study,energy release rate are calculated numerically for vari-ous delamination lengths,applied loads and the orientation of plies. It is found that the de-lamination growth depends on G1.G, and the effect of G, can be neglected. The global buckling due to delamination growth under high loads would cause a rapid .extensive de-lamination growth.