复合材料圆柱壳中心受横向集中载荷作用的渐进破坏非线性有限元分析

Progressive failure nonlinear finite element analysis of cylindrical composite shells under a transversely centre concentrated load

旨在建立能够正确预计复合材料圆柱壳的屈曲和后屈曲渐进破坏行为的模拟策略。采用有限元方法和Hashin失效准则进行模拟,基于该失效准则编写了用户材料子程序,然后插入到商用有限元软件ABAQUS中。分析了中心受横向集中载荷作用复合材料圆柱壳板,壳板的2条直边弹性支持,2条曲边自由。为了探讨弹性边界条件和集中载荷作用点应力集中的影响,将有限元分析结果与文献中的试验结果进行了比较,提出了一种合理的弹性边界选取依据。研究结果表明,在建模中考虑了弹性边界和集中载荷作用点处存在的应力集中后,本文中模拟的结果与文献中的试验结果比较接近,模拟精度明显高于文献中报道的结果。这也验证了本文中建立的模拟策略的合理性。

The purpose of this investigation is to establish a modeling strategy for accurately predicting the buckling and the progressive failure in the post-buckling of cylindrical composite shells. Finite element method was employed and Hashin failure criterion was used. A user material subroutine based on the failure criterion was developed and inserted into the commercial finite element software ABAQUS. Cylindrical composite shell panels subjected to a transversely concentrated load at its centre were analyzed. Two straight edges of the panel were elastic support and two curved edges were free. Finite element results were compared with the existing experimental data in the literature to investigate the effect of the elastic support conditions and the stress concentration caused by the concentrated load. A reasonable criterion for simulating the correct elastic boundary condition was proposed. It is found that if the elastic support and the stress concentration at the small area of the concentrated load point are considered in the modeling, the simulated results are fairly close to the experimental data and are much better than the existing predictions. Therefore, the rationality of the established modeling strategy is validated.