Análise comparativa da altura, volume, consumo de aço e custo das vigas de armadura simples, dupla e de seção T

Abstract

In the construction of any building, residential or commercial, an important point is to increase economic efficiency. In view of this, the engineer looks for ways to optimize the building, as in the dimensioning of reinforced concrete parts. In the engineer's daily challenge, one of the structural elements that has the most ways to be worked is the beam. It can have variations both in its geometry and in the material that constitutes it, so that there are countless possibilities of beams to be chosen according to the engineer's needs. In this work, the three most common types of beams in reinforced concrete structures were considered, beams with simple reinforcement, beams with double reinforcement and beams with T section. control in which the theoretical span of the beams was varied, from meter to meter, from 2 to 10 meters in length, for the same loading condition. Furthermore, for analysis purposes, the fck and the design conditions were also varied. These refer to the ultimate limit state (ELU) and service limit state due to excessive deformations (ELS), with and without the use of back deflection. All beams were designed with the aim of achieving the lowest possible height, and the results used in the analysis consist of height, concrete volume, steel weight and beam cost. It was concluded that the back deflection promotes a great increase in the height yield of the beams, being able to decrease about 22% of the height of the single reinforcement beam, 16% of the T-section beam or 10% of the double reinforcement beam. Also, with regard to height, it was verified that the beam of T section has the smallest height per span, being about 20% smaller than the beam with single reinforcement or 10% smaller than the beam with double reinforcement. The beam with the highest total cost was the double reinforcement beam, followed by the single reinforcement beam and the T-section beam.