| Título: | A 2D boundary element formulation for potential-based cohesive fracture |
| Autor: | Gustavo de Oliveira Daumas |
| Programa: | Engenharia de Infraestrutura Aeronáutica |
| Área de Concentração: | Infraestrutura Aeroportuária |
| Orientador : | Francisco Alex Correia Monteiro |
| Coorientador : | Sérgio Gustavo Ferreira Cordeiro |
| Ano de Publicação : | 2023 |
| Curso : | Mestrado Acadêmico |
| Assuntos : | Análise estrutural |
| t | Mecânica de fratura |
| t | Equações não-lineares |
| t | Método de elementos de contorno |
| t | Engenharia estrutural |
| Resumo : | The present work proposes an intrinsic potential-based mixed mode cohesive dual boundary element formulation for nonlinear fracture problems. The nonlinear system of equations for intrinsic cohesive models can be achieved by introducing local cohesive stiffness matrices into the boundary element equations. A potential-based cohesive model, the so called Park-Paulino-Roesler (PPR) model, was introduced into the equations to simulate crack problems due to its remarkable ability to capture the fracture phenomenon in a range of materials. A path-following method is proposed to solve the nonlinear system of equations by the direct control of one of the known degrees of freedom. The loads are divided into two groups: one in which the load is perfectly known and another in which only the direction is known. The magnitude (or load factor) of the latter is determined with respect to the equilibrium of the boundary fields (indirectly controlled) and an additional path-following constraint equation. For each iteration, the corrections to the boundary fields are obtained in a partitioned manner, in which the load factor is calculated independently using the direct control of the degree of freedom as the path-equation. Finite element path-tests and cohesive crack propagation problems with numerical results available in the literature were used to validate the developed model. |
| Data de Defesa : | 20/04/2023 |
| Texto na íntegra : | [Visualizar] |