带旋转自由度C^0类任意四边形板（壳）单元

基于Ｒｅｉｓｓｎｅｒ－Ｍｉｎｄｉｌｉｎ板弯曲理论和Ｖｏｎ－Ｋａｒｍａｎ大挠度理论，采用单元域内和边界位移插值一致性的概念，将四节点等参弯曲单元与Ａｌｌｍａｎ膜变形二次插值模式相结合，对层合板壳的大挠度分析提供了一种实用的带旋转自由度的四节点Ｃ＾０类板单元。大量算例表明：该单元对板壳结构的线性强度、稳定性和后屈曲分析都表现出良好的收敛性和足够的工程精度。

A new 4-node C~0 quadrilateral plate/shell element with drilling degree of freedom

HT5SS]A new four node C 0 quadrilateral element is based on the Reissner\|Mindlin moderately thick plate theory and von Karman moderately large deflection assumptions is presented to analyse large deflection problems of composite plate/shell structures. Shear locking is overcome by using an independent interpolation function for transverse shear strains which is consistent within element domain and at element boundaries. The present element has a drilling normal rotation. The drilling degree of freedom contributes only to the membrane displacement components interpolated by a two\|order interpolation function which is for overcoming the singular behaviour when the finite element equations are assembled at points where elements are co\|planar in local coordinates. The numerical examples have demonstrated that the present element has good performance for linear bending, nonlinear bending, buckling and postbuckling analyses of various laminated plate and shell structures.