Caracterização mecânica e simulação numérica de concreto de alto desempenho reforçado com fibras metálicas

Abstract

Fiber-reinforced high performance concrete (HPC) was designed to overcome the limitations of traditional concrete such as low tensile strength and brittle fracture. It is a material composed of regular cement, fine aggregates, hyperplasticizer additive and steel fibers, with low water-cement ratio and compressive strength greater than 60 MPa. Fiber-reinforced HPC is increasingly being applied to building structures in countries such as the US and Japan. There is no consensus on which constitutive model should be used to represent its behavior. In this work, we want to fill the knowledge gap by conducting a study about the material characteristics in order to choose which model best represents its behavior. This work aims to perform HPC experiments with and without fibers and compare their results to conventional concrete using computational models. Two nonlinear elastic models were used in this work. The CEB-FIP (1990) was used for the 0% fiber mix and Mansur et al. (1999) was used for the two fiber reinforced HPC mixes. They seem to represent well the behavior of the material. After that, mModel and Lee e Fenves (1998) Model are studied in order to perform the concrete behavior. Only m Model can represent HPC softening in numeric applications. Finally, Espion (1993) benchmark is performed and it is concluded that HPC has a much higher load capacity than conventional concrete.