Modularization of complex structures allows for faster, higher quality, and more cost-effective design. However, sharing information about the geometry and materials of the modules presents a security risk when multiple companies are involved in the project. In such cases, an equivalent model can be developed for secure sharing purposes. The equivalent model should be able to predict the nonlinear geometrically behaviour of the module. This paper aims to develop a nonlinear equivalent model for substructures based on a combination of the Craig-Bampton technique and model order reduction. The paper provides explicit formulas for constructing the reduced-order matrices of the equivalent model based on third-order and fifth-order modal polynomial approximations. The ability of the equivalent models to simulate the geometrically nonlinear static displacements of structures is evaluated through two numerical examples of beam structures.

中文翻译：

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采用子结构技术的几何非线性曲梁结构降阶模型

复杂结构的模块化可以实现更快、更高质量和更具成本效益的设计。然而，当多个公司参与该项目时，共享有关模块的几何形状和材料的信息会带来安全风险。在这种情况下，可以出于安全共享的目的开发等效模型。等效模型应该能够预测模块的非线性几何行为。本文旨在开发一种基于 Craig-Bampton 技术和模型降阶相结合的子结构非线性等效模型。该论文提供了基于三阶和五阶模态多项式近似构建等效模型降阶矩阵的显式公式。通过两个梁结构的数值算例评估了等效模型模拟结构几何非线性静态位移的能力。