Uso de métodos numéricos para o ensaio de resistência à tração por compressão diametral do concreto

Abstract

The tensile by diametrical compression test, also known as Brazilian tensile test is the most utilized to find the tensile resistance of the concrete, because it is an ease test and have a low cost compared to other tests. Such a test consist in a radial compression of a sample until it breaks by tensile. On the surfaces between the sample and the universal testing machine is recommend the use of wooden strips so the load is distributed in a better way over the material of study. The width of the wood strip directly influence the results of the resistance test. One way of analysis that has been growing over the years is the use of numerical methods in fracture bodies of various materials, so in this work is used the Discrete Element Method and the Finite Element Method for the study of the Brazilian tensile test. The results obtained shows that the tensile by diametrical compression resistance increases with the increment of the width of the wood strip, until a relation between the diameter and width of the sample of 0,25; after this value the direct tensile resistance decrease. A random set of resistance values for the different modules size tested were found, not allowing a description of the real behavior of the tested samples. In the simulations, the cracks propagated vertically, form the zone in contact with the wood strip to the center of the sample.