Tesis doctoral de Sergio Blanco Ibañez
This work presents a reformulation of the continuum strong discontinuity approach applied to the numerical simulation of material failure in structures. The goal pursued has been the improvement of the robustness of this kind of numerical analysis. It has also provided a set of tools that guarantees the accuracy of the results. the continuum strong discontinuity approach reproduces the strain localization phenomenon due to the material softening. As opposed to the discrete approaches, this methodology uses a continuum stress-strain format to describe the whole process of the material exhaustion. Thanks to the regularization (reinterpretation) of the kinematics of the problem and the softening modulus it is guaranteed that the dissipation of the material model is given by the superficial density of fracture energy. Additionally, the use of a thermal-like algorithm to capture and manage the strain localization surfaces makes possible to deal with the numerical study of multi-fissure problems. the improvement of the robustness in the numerical analysis has been achieved by adopting the symmetric kinematically consistent formulation and formulating a new integration scheme, called impl-ex, that assures that the algorithmic tangent operators in the problem remain positive definite. the accuracy of the numerical result has been accomplish by an error-control algorithm and by a new arc-length method. This two algorithms have been developed specifically for the integration scheme impl-ex. this formulation has been applied to the study of two characteristic phenomena in fracture mechanics: the study of the size effect in geometrically comparable structures and the study/measurement of the fracture processing length. finally, a series of numerical examples of material failures in three-dimensional structures is presented. These examples have been divided in three groups: examples in which the failure mode is predominantly in mode i, examples in which the failure mode is
Datos académicos de la tesis doctoral «Contribuciones a la simulacion numerica del fallo material en medios tridimensionales mediante la metodología de discontinuidades fuertes de continuo.«
- Título de la tesis: Contribuciones a la simulacion numerica del fallo material en medios tridimensionales mediante la metodología de discontinuidades fuertes de continuo.
- Autor: Sergio Blanco Ibañez
- Universidad: Politécnica de catalunya
- Fecha de lectura de la tesis: 27/04/2007
Dirección y tribunal
- Director de la tesis
- Francisco Javier Oliver Olivella
- Tribunal
- Presidente del tribunal: joan ramón Casas rius
- Galvez ruiz Jaime Carlos (vocal)
- Brito pina Carlos Alberto (vocal)
- Luis Manzoli osvaldo (vocal)