Análise experimental sobre o efeito da armadura de cisalhamento em vigas submetidas a cargas de impacto

Abstract

The reinforced concrete beams in bridges, viaducts and footbridges are often subject to wear and tear, not only by wind and rain, but also by direct impacts on the structure, which can lead to ruin. Due to recent reports of falls of viaducts and footbridges, and the fact that the shear reinforcement analysis in reinforced concrete beams submitted to exceptional loads is lightly explored in the Brazilian academic scenario, it was considered important to develop this study. For the analysis of the shear reinforcement in reinforced concrete beams submitted to impact loads, an experimental study was carried out on two reinforced concrete beams: one with 90 ° shear reinforcement of the longitudinal reinforcement; and the other with the shear reinforcement at 45 ° of the longitudinal reinforcement. The beams were subjected to equal number of impacts, and thus, the behavior of both beams could be analyzed. From this experiment, it was concluded that the arrangement of the shear reinforcement influences the way in which the cracks appear in the beams and, in relation to the resistance, it was verified that the shear reinforcements arranged at 45 ° allow a better joint behavior of the resistance mechanisms of the beam.