Otimização de estruturas treliçadas geometricamente não lineares submetidas a carregamento dinâmico

• Ano de defesa: 2019
• Autor(a) principal: Martinelli, Larissa Bastos
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Engenharia Civil; Centro Tecnológico; UFES; Programa de Pós-Graduação em Engenharia Civil
• Palavras-chave em Português: Structural optimization; Geometric nonlinearity; Dynamic analysis; Trusses; Structural hollow-sections; Steel structures; Otimização estrutural; Não linearidade geométrica; Análise dinâmica; Treliças; Estruturas de aço; Perfil tubular; Dinâmica estrutural; Treliças (Construção civil); Aço - Estruturas; Engenharia Civil; 624
• Link de acesso: http://repositorio.ufes.br/handle/10/11270

This study addresses the optimization of lattice structures with geometrically nonlinear behavior under dynamic loading. The formulated optimization problem aims to determine the cross-sectional area of the bars which minimizes the total mass of the structure, imposing constraints on nodal displacements and stresses. In order to solve this optimization problem, it was developed a computational program on MATLAB®, using the Interior Point method and the Sequential Quadratic Programming method, the algorithms of which are available on Optimization Toolbox™. It was included routines for grouping the bars and to convert the optimal solution obtained using continuous design variables in commercial values of structural hollow-sections. The space truss nonlinear finite element is described by an updated Lagrangian formulation. The implemented geometric nonlinear dynamic analysis procedure combines Newmark’s method with Newton-Raphson type iterations, being validated by comparison with solutions available in the literature and with solutions obtained using ANSYS® software. Examples of plane and space trusses under different dynamic loading are solved using the developed computational program. The results show that: the Sequential Quadratic Programming method is the most efficient to solve the studied optimization problem, consideration of structural damping can lead to a significant reduction in the total mass, the use of the conversion procedure for commercial sections provides solutions in favor of security and the grouping of bars generates a satisfactory duration for the optimization process.