Eventos Anais de eventos
COBEM 2023
27th International Congress of Mechanical Engineering
Determination of the reinforcement steel area in pure bending considering the stress-strain diagram with the creep of concrete
Submission Author:
Alexandre de Macêdo Wahrhaftig , BA , Brazil
Co-Authors:
Alexandre de Macêdo Wahrhaftig, Rodrigo Oliveira da Silva Conceição , Iago Gonçalves de Oliveira, Cibele Mota Menezes
Presenter: Cibele Mota Menezes
doi://10.26678/ABCM.COBEM2023.COB2023-0456
Abstract
When dimensioning the reinforced concrete structures, the engineer establishes an area of reinforcement steel intending to, together with the compressed region of concrete, find the balance of the analyzed section. Concrete is a brittle material and therefore does not have high tensile strength. For this reason, the introduction of reinforcement bars in tensioned region is necessary so that the balance of the section is established. In this context, the knowledge of the stress-strain diagram of materials is essential. In the case of concrete, its viscoelastic behavior still needs to be observed in that context. Viscoelastic materials exhibit creep, characterized by the increase of strains over time, even if the stress level is maintained unchanged. Creep modifies the stress-strain diagram of the concrete and, therefore, the internal lever arm that defines the balance of forces in the section. In this work, the calculation of the reinforcement steel area of sections in pure bending is studied by taking the stress-strain diagram of the concrete modified by the creep of the material. A rectangular section, submitted exclusively to the action of a positive bending moment, is examined. The definition of the reinforcement steel area is done for different time instants.
Keywords
reinforced concrete structures, Stress-strain diagram, Creep of concrete, Pure bending, Reinforcement steel area
