Based on the updated Lagrangian description, the incremental equilibrium equations of triangular plate shell elements for geometrically nonlinear problem are derived.
基于修正的拉格朗日描述，系统推导了三角形平面壳单元用于几何非线性问题分析时的增量平衡方程。
The combined structures which are made of bar, beam, membrane, plate and shell elements are used broadly in engineering.
杆、梁、膜以及板壳等多单元组合结构被广泛地应用到工程实际当中。
Through years of researchers' persistent efforts, quite a number of plate and shell elements have been presented and many of them are excellent.
经过众多研究者数十年的努力，已经有为数可观的板壳单元出现，其中不少是品质优良的。
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