Eventos Anais de eventos
COBEM 2019
25th International Congress of Mechanical Engineering
EXPERIMENTAL ANALYSIS OF THE SIZE EFFECT IN QUASI-FRAGILE MATERIALS
Submission Author:
Mylena Barcellos da Silva , RS
Co-Authors:
Leandro Friedrich, Luis Kosteski, Vicente Puglia, Édiblu Cézar, Mylena Barcellos da Silva, Ignacio Iturrioz, Angelica Colpo
Presenter: Mylena Barcellos da Silva
doi://10.26678/ABCM.COBEM2019.COB2019-0636
Abstract
The scale effect is a phenomenon characterized by the change in structural behavior when dimensional variations occur, as stress, strain and fatigue resistance of the material, for example. When the material by nature does not show significant signs of strain, the problem is even more complex. Therefore, the study of phenomena in quasi-fragile materials, that are incapable of presenting purely plastic deformations, is still an open topic. A methodology widely used for the monitoring of structures and that has been applied to evaluate the scale effect is the acoustic emission technique, used to obtain information about how and where the structure cracks. Therefore, the aim of this work is to capture the scale effect in quasi-brittle materials mainly using the acoustic emission technique but also observing the mechanical behavior of the material. Three sample sizes made of expanded polystyrene are tested in a three point flexural test. The results are presented in terms of the global stress-strain curves of the material as well as the analysis of the amplitude distribution and the number of acoustic emission events captured for each different sample size. The obtained experimental results were in great agreement with the known fractal theory and clearly showed a size effect.
Keywords
quasi-brittle materials, size effect, acoustic emission
