A design tool for the analysis of reinforced and prestressed concrete columns

Abstract

This article aims to describe an automatic calculation algorithm developed for the analysis of reinforced concrete and / or prestressed concrete columns. The article describes two analysis types: sectional analysis and analysis on the element. The sectional analysis consists in the generation of three characteristic curves: bending moment - curvature (M-1/r), axial force - bending moment (N-M) and bending moment – bending stiffness diagrams. The analysis on the element provides the height – displacement (H-w) diagram, obtained by using the finite element method (FEM). For the two analysis, the calculation approach and the implementation of the algorithm is briefly described by the mathematical equations used. To ease the usage of the algorithm an application was developed in MATLAB appDesigner. For validating the algorithm, the results were compared with those obtained from experimental tests in the laboratory but also with numerical simulations using commercial computational software based on FEM. MATLAB programming language was used to implement the algorithm, while results of the analysis proved to be conservative when compared to the experimental ones. Moreover, the bending moment resistance for prestressed concrete columns using bonded tendons is better estimated with at least 10% when compared with a commercial software, based on fiber-based cross-section nonlinear analysis.