Nonlinear models for design of circular RC columns under ultimate and service states

Abstract

The present paper is dedicated to the ultimate and to the service design of circular reinforced concrete sections under axial load and bending moment, according to Eurocode 2 [1]. The objective of the present work is to develop design equations for circular reinforced concrete sections, solving the equilibrium equations by mathematic symbolic software. The concrete only supports compressive stresses and the steel can hold both tension and compression. The nonlinear equation of EC2 [1] is used for compressed concrete in the ultimate design. The steel is considered to have a linear elastic constitutive law up to the yield stress, followed by a plastic behaviour. The ultimate design condition is posed in terms of maximum strains for the most compressed concrete fibre or for the tensioned steel bar, permitting the definition of interaction abacuses, shown in the present paper.