Analise numérica e experimental da fratura em materiais quase frágeis

Abstract

In the present work the experimental study and the simulation of simple tensile tests are carried out to analyze the fracture in quasi fragile materials. Three types of expanded polystyrene for the make six models of specimens with dimensional variations are used. However to avoid repetitiveness, is shown and discussed the experimental and numerical results obtained for one type of expanded polystyrene and the results for the other are shown in the appendices. It also analyzed the mechanical properties of the materials studied and the data is subsequently used in the simulations performed by the Lattice Discrete Element Method. It addition, this method is used in Abaqus environment for performing simulations in which part of the specimen is patterned into discrete elements and the remainder in finite elements. The tensile tests showed that the materials suffer a size effect, and the bigger specimens had a shown low rupture strain. The LDEM used to simulate the tests proved to be a good tool to analyze the fracture and size effect on quasi-fragile materials, moreover, their use in Abaqus environment showed that the samples do not strain only in the central region. Simulations in LDEM and LDEM-Abaqus showed that it is possible to simulate only the central region of the specimens provided that are not taken into account the values of elastic energy. Furthermore, by a subroutine implemented in LDEM it was possible to create a structure damage map, allowing observation of the location of the damage.