Estudo de Modelos de Campo de Fase para Análise de Fratura
Rafael Gollner Bayão
Undergraduate thesis - 2021
The development of models that use the Finite Element Method formulation to computational fracture analysis is a wide research field. It can be cited several formulations, which were published throughout the last decades, that allow the description and prediction of the behavior from structures with various materials, conditions, and physical properties. In this sense, the Elastic Degradation models have vast literature and formulations with exceptional results for many analysis situations. Besides that, recently, the Phase-field models have been gaining a spotlight for their capacity to predict crack paths precisely and achieving also great results. Therefore, due to recent publications in Phase-field models development, this work propose is making a literature review and implementation of theoretic formulations of this method, along with solution methods, constitutive models, and characteristic functions for quasi-static analysis. Hence, embodying new tools to a numerical simulation program, so it may be possible to perform a comparative analysis between the results from both Phase-field and Elastic Degradations models.
Ambiente gráfico interativo para diagrama de interação de seções de concreto armado
Filipe de Paula Braga Silva, Flavio Torres da Fonseca, Leandro Augusto Campelo de Barros, Marcelo Paixão Pinto Rodrigues
Undergraduate thesis - 2005
This work aims at the implementation of a graphical and interactive environment for obtaining interactive diagrams of reinforced concrete sections. The section may have any polygonal geometry and any steel bars arrangement is accepted. The section can be solicited from both normal force and moments, which is enough to represent from a simple flexion to an oblique flexion. In order to find the position of the neutral line in this case it is necessary to obtain both the translation and the rotation of the neutral line through an iterative process. For each position of the neutral line which satisfies the equilibrium, the solicitant stress state is calculated and compared to the given one until they become equal to each other within a certain tolerance. The implementation of the graphic environment follows the Objected Oriented Programming methodology using Java. The obtained diagrams are based on the discretization of the section into a list of points on its plane. The constitutive equations of the steel and concrete were taken from the NBR-6118:2003.