Estudo do comportamento à tração de corpos de prova de concreto armado

Abstract

Due the gap created by the lack of data and a specified process for the obtention of real values of tensile strength, is created the need of present/develop an efficient and trustful way for obtention of this data, which are relevant for the best utilization/optimization of the tensile strength in civil construction field. This study evaluated the direct tensile strength of reinforced and not-reinforced concrete through tests of direct traction in proof bodies with “dogbone” shape which have elongated tips, a transversal section and length of 6 x 4 x 60 centimeters respectively. Steel bars with diameters of 6,3, 8 and 10 millimeters were insert in the proof bodies. The mix of concrete used was 1:2,17:2,94:0,64. For the consistence determination of concrete was used the slump test according NBR NM 67. Compression tests and traction tests were performed with age of 28 days. The obtained results were presented by tension versus strain and tension versus displacement graphs that were compared with results found in similar bibliographies. It was concluded that the insertion of reinforcement provided a significative increase in concrete strength, nevertheless the first cracking happens in similar tensions to the direct tension strength of not-reinforced concrete, irrespective to the bar diameter.