Estudo experimental de vigas de concreto armado com furos: análise do comportamento à flexão considerando furos com e sem armadura de reforço

Abstract

The lack of compatibility between projects, combined with execution problems within the construction site, results in moments of rework that costs time, resources and may pose a risk to the structure. A very common rework in civil construction is the need to make openings in already concreted beams for the passage of pipes. In many cases, these openings were not considered during the design phase, which can compromise the strength of the reinforced concrete structure, since it was not adequately reinforced. Therefore, this study aims to experimentally compare the difference in strength of reinforced concrete beams with holes, with and without the presence of reinforcement in the region. For this purpose, a total of fifteen reinforced concrete beams were manufactured, divided into five different groups: reference beams without openings, beams without reinforcement in the area of the 50mm and 75mm diameter hole, and beams with reinforcement in the 50mm and 75mm hole area. The beams were subjected to four-point bending tests, and the rupture strength was measured. It was concluded that, although an execution issue significantly affected the strength of the reinforced beams, causing them to fail below the calculated load, the reinforcement was effective in minimizing cracks around the opening and aided the 75mm beams in not failing due to shear forces in the opening region.