一种中厚扁壳杂交应力单元

本文建立了一种任意形状四节点杂交应力扁壳单元,考虑了横向■切的效应,可用于中厚壳及薄壳。基于Hellinger-Reissner变分原理,以单元内不相容位移为Lagrange乘子放松了单元应力的平衡约束,并以应力在不相容应变上做功为零做为补充条件,消去了单元内多余的应力参数。此单元具有最少的应力参数,具有坐标不变性。例题计算结果表明,此单元的性能是相当好的。

A MODERATE THICK SHALLOW~#SHELL HYBRID STRESS ELEMENT

An arbitrary shallow shell hybrid stress element with4-node was suggested in the paper.Taking account of the transverse shear it can be used for moderate thick and thin shell analysis·Based on Hellinger-Reissner variational principle the equilibrium equations in an. element can be relaxed. Taking the incompatible part of the assumed displacements in the element as Lagrangemultiplier and making the work done by the assumed stresses on the incompatible strain equal to zero the unnecessary stress parameters can be eliminated in the element. This element is invariant and contains the minimum number of stress parameters. The results of some examples show the nume rical function of this element is considerable good