非对称铺层复合材料板室温形状的非线性有限元分析

 由于一般铺层复合材料板壳存在拉伸-弯曲、拉伸-扭转等耦合效应,在温度变化时将出现垂直于中面方向的翘曲变形,给工程使用和理论分析带来了极大的不便。但另一方面,利用非对称铺层复合材料板壳可以有效地减轻结构的重量,并可能提供利用平面模具制造曲面层合壳的新工艺。

NONLINEAR FINITE ELEMENT ANALYSIS OF THE ROOM-TEMPERATURE SHAPE OF UNSYMMETRICALLY LAMINATED COMPOSITES

In the paper, room-temperature shape of unsymmetrically laminated composites is studied using finite element method. This is a nonlinear finite element problem with multiple equilibrium states. A degenerated three-dimensional shell element is adopted and the incremental Newton-Raphson method is used to silve the nonlinear equilibrium equation. The different eqilibrium states are obtained by prespecifying initial deflection. The tangential stiffness matrix is decomposed into L] D] L] to determine the stability of equilibrium. Experiment is also done and the numerical results poncide on the whole with the experimental results.