Análise metodológica e numérica do comportamento de colunas de concreto armado sob efeitos de compressão axial

Abstract

This paper presents a comparative and numerical analysis of the behavior of reinforced concrete columns subjected to axial compression, using the Discrete Bar Element Method (LDEM). The main objective of the research is to evaluate the resistance capacity and instability effects, such as buckling, of columns under different load conditions. To this end, numerical simulations were carried out with variations in geometric properties, types of loading and reinforcement, using Abaqus/CAE software for modeling and analysis. The study highlights the importance of second-order effects in slender columns, which combine axial loads and bending moments, taking into account geometric and material nonlinearity. The simulations also considered the impact of eccentric loads and disturbances in the mesh, allowing the analysis of critical phenomena that can compromise structural stability. In addition, the numerical results were compared with experimental data and technical standards, such as NBR 6118, to validate the model. The results indicated that LDEM is efficient at predicting the behavior of columns, providing accurate estimates of maximum resistance, deformations and failure modes. It was observed that columns with well-dimensioned reinforcement have a greater capacity to withstand critical loads and avoid permanent deformations. The simulations also showed that geometric disturbances and eccentric loads increase the propensity to buckling, especially in very slender columns. In conclusion, the numerical method applied is a valuable tool to complement experimental tests, providing detailed insights into structural performance. The work contributes to the improvement of civil engineering projects, reinforcing the importance of considering factors such as slenderness, load eccentricity and material properties in the analysis and design of reinforced concrete columns. Keywords: Reinforced concrete, Axial compression, Buckling, Slender columns, Bar-formed Discrete Element Method.