Computational methodology for the optimal design of steel truss frames integrating MATLAB and FEA platforms

Abstract Seeking to define more robust and executable structures, this article presents a computational framework for the optimal design of steel truss frames, which integrates two software of great prominence in structural engineering, MATLAB and ANSYS. Computational interfaces were created to enable the automation of the iterative optimization process. The optimization algorithm and computational interfaces were developed on the MATLAB platform, while structural analyses were performed with the ANSYS Mechanical APDL platform. Some details of the computational implementation are presented herein. The objective is to minimize the cost of structures by determining the optimal positioning of nodal coordinates and the optimal choice of commercially available structural profiles - shape and size optimization, respectively. For shape optimization, a computational model was defined to automatically generate the geometry of the structure, maintaining some intrinsic relations of symmetry and collinearity between elements. The design constraints are critical nodal displacements, stresses, and slenderness of elements, following the requirements of ABNT NBR 8800:2008. To exemplify the application of the proposed methodology, this article presents the optimal design of trusses for roofs of industrial sheds, considering its non-linear geometric behavior, typical of this type of structure.

摘要 旨在构建更具鲁棒性且可落地的结构方案，本文提出了一种用于钢桁架框架优化设计的计算框架，该框架集成了结构工程领域极具影响力的两款软件——MATLAB与ANSYS。本文搭建了计算接口以实现迭代优化过程的自动化：优化算法与计算接口均基于MATLAB平台开发，而结构分析则依托ANSYS Mechanical APDL平台完成。本文还阐述了计算实现的若干细节。本研究的目标为通过优化节点坐标位置与商用结构型材的选型，分别实现形状优化与尺寸优化，从而最小化结构造价。针对形状优化，本文构建了可自动生成结构几何模型的计算框架，且保留了构件间固有的对称性与共线性约束关系。设计约束需满足关键节点位移、构件应力与长细比的限值要求，符合ABNT NBR 8800:2008标准的规定。为验证所提方法的应用效果，本文以工业厂房屋顶桁架的优化设计为例，考虑了此类结构典型的几何非线性行为。