精化杂交Mindlin板单元的几何非线性分析

基于放松单元间连续性要求约束的广义变分原理,建立了用于几何非线性分析的非协调四边形精化杂交Mindlin板元,其非线性单元刚度矩阵可按假定应变模式分解.本文列式与现有非线性杂交混合列式的主要区别在于,它吸收了现有线性杂交元列式的所有优点,引入了非协调模式和正交化.数值结果表明,正交化法可有效地改善单元的计算精度和效率,非协调模式可克服Mindlin板的自锁问题.

REFINED HYBRID MINDLIN PLATE ELEMENT FOR GEOMETRICALLY NON-LINEAR ANALYSIS

Based upon a generalized variational principle, which relaxed the inter-element continuity requirements, a novel refined hybrid Mindlin plate element is developed, its non-linear element stiffness matrices are decomposed into a series of matrices with respect to the assumed strain modes. The formulation presented in this paper is different from any other non-linear mixed/hybrid element formulation all successful experience of linear hybrid formulation is absorbed into the formulation(adding non-conforming modes and realizing orthogonalization) Numerical results show that the present approach is more effective than any other non-linear hybrid element formulation over the accuracy and computational efficiency. In addition, non-conforming modes can also overcome the shear locking effect.