复合材料板壳结构的杂交/混合有限元分析

A HYBRID/MIXED FINITE ELEMENT ANALYSIS FOR COMPOSITE PLATES AND SHELLS

本文建立了一个9节点Lagrange退化壳杂交/混合有限元模型,以用于复合材料板壳结构的有限元分析。该有限元模型基于修正的Hellinger-Reissner原理,位移和应力均采用分离法思想,使得这一单元不仅具有下列优点:1.位移和应力计算精度都比较高;2.消除了多余零能变形模式;3.具有厚薄通用性;4.具有几何不变性,并且较之一般杂交/混合单元计算工作量进一步降低。单元还考虑了横向剪切影响。计算实例表明,本单元关于复合材料浅壳和深壳的解都与参考解吻合很好,且收敛很快。

In this paper,a new finite element-Lagrange degenerated shell hybrid/ mixed element with 9 nodes is developed for the structural analysis of composite platesand shells. The element is based upon a modified Hellinger -Reissner principle, which has following advantages:high accuracy for evaluation of stresses and displacemens,elimination of redundant zero-energy deformation modes, apparently weakened locking effect and invariance with reference coordinates. Using this kind of element the efficiency in computation is improved as compared with other hybrid/mixed finite element and the transverse shear effect is taken into account. Several numerical examples are presented. Numerical studies revea that the accurate and convergent solutions for fider-reinforced composi shallow and deep shells are obtined in comparison with that in re-ferences.