Análise da resistência à flexão de vigas tipo perfil U submetidas a ensaios de corrosão acelerados com diferentes tempos de exposição

Abstract

This work presents an experimental study to seek to understand the influence of surface modification by accelerated corrosion process in relation to the resistance of metalic beams. Were used eight specimens with U profile and A-36 steel type, without coating, with height of 75 mm, 40 mm wide, thickness of 2 mm and length of 300 mm. The eight specimen were divided into four groups, where three of the four groups stayed respectively, one, four and nine weeks in accelerated corrosion test, using the salt spray chamber. The fourth group was defined as being the control group and it wasn't submitted to the corrosion test. The corrosion test was conducted in laboratory with specialized personnel and in the end was provided a report for each group and their respective time of exposion. For the resistance test was opted to perform bending tests, accordingly with the availability of laboratory equipments, therefore, allowing an three point test. This test started with the control specimens for having a base value compared to the other groups that were tested later. There was also made a comparison related to the weight of the control specimen related to the other groups. The experiment first noted that for the pieces exposed to accelerated corrosion test, the superficial coating is imperative to ensure the integrity of the specimens. The increase on the weight of the specimen, have relation with the accumulation of sodium chloride particles in the surface of the pieces. Finally was evident that the resistance of the specimen decreases as a function of the time elapsed, because the grater the time of exposion is in the salt spray chamber, the grater is the lost of resistance. [resumo fornecido pelo autor]