Contribuição ao estudo do comportamento mecânico do concreto utilizando diferentes modelagens em elementos finitos na escala mesoscópica

• Autor(a) principal: Quaresma, Wanessa Mesquita Godoi
• Data de Publicação: 2016
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• dARK ID: ark:/38995/0013000004673
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/6796
• topic: Modelos multiescala; Concreto; Fratura coesiva; Plasticidade; Escala mesoscópica; Multiscale model; Concrete; Cohesive fracture; Plasticity; Meso-scale; ENGENHARIA CIVIL::ESTRUTURAS

This work deals with the study of the concrete mechanical behavior using a two-dimensional numerical modeling in mesoscopic scale. The material is considered to be composed of three phases consisting of the interface zone matrix and inclusions, where each constituent is modeled properly. In the representative volume element (RVE) inclusions of as various shapes and randomly arranged are considered. The interface zone is modeled by finite elements where a model of fracture and contact recently proposed is incorporated. On the other hand, the transition zone is modeled by triangular finite elements where the Mohr-Coulomb model with lower strength characteristics compared to the mortar, is used. Inclusion is modeled as a linear elastic material and the matrix is considered as elastoplastic materials governed by the Mohr-Coulomb model. Our main goal is to show that a formulation based on computational homogenization is an alternative to complex macroscopic constitutive models for the mechanical behavior of brittle materials using a procedure based on the Finite Element Method and a multiscale theory. Examples changing the form of aggregate, their volume fraction and distribution in RVE, as well as various strategies for modeling the transition zone are shown to illustrate the performance of the proposed model. The results evidence that the proposed modeling leads to are promising results for employment in a multiscale modeling. Also, this work shows the importance of parametric identification of fracture and contact model in the microstructural analysis of concrete.