A DNN-Based Surrogate Constitutive Equation for Geometrically Exact Thin-Walled Rod Members

Autor(es)

Kassab, Marcos Pires ; Campello, Eduardo de Morais Barreto ; Ibrahimbegovic, Adnan

• Tipo de documento: Artigo Científico
• Fonte: COMPUTATION; v. 13, n. 3, p. 24-pg., 2025-03-03.

Resumo

Kinematically exact rod models were a major breakthrough to evaluate complex frame structures undergoing large displacements and the associated buckling modes. However, they are limited to the analysis of global effects, since the underlying kinematical assumptions typically take into account only cross-sectional rigid-body motion and ocasionally torsional warping. For thin-walled members, local effects can be notably important in the overall behavior of the rod. In the present work, high-fidelity simulations using elastic 3D-solid finite elements are employed to provide input data to train a Deep Neural Newtork-(DNN) to act as a surrogate model of the rod's constitutive equation. It is capable of indirectly representing local effects such as web/flange bending and buckling at a stress-resultant level, yet using only usual rod degrees of freedom as inputs, given that it is trained to predict the internal energy as a function of generalized rod strains. A series of theoretical constraints for the surrogate model is elaborated, and a practical case is studied, from data generation to the DNN training. The outcome is a successfully trained model for a particular choice of cross-section and elastic material, that is ready to be employed in a full rod/frame simulation. (AU)

• Processo FAPESP: 20/13362-1 - Mecânica, estocástica e controle com acoplamento de códigos: otimização de fazendas terrestres ou oceânicas de turbinas eólicas com pás flexíveis através da ótica de sistemas multi-corpos
• Beneficiário: Paulo de Mattos Pimenta
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 22/15644-0 - Modelo cinematicamente exato para barras de paredes delgadas com distorção da seção transversal e deformações finitas
• Beneficiário: Marcos Pires Kassab
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 23/16272-1 - Um modelo cinematicamente exato de ordem reduzida para fratura em elementos de paredes delgadas
• Beneficiário: Marcos Pires Kassab
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado