Evaluation of Mixed Formulation for Modelling RC Columns with Bond Slip

Abstract

Modelling composite members is a challenge for the computer simulation of structural response under extreme loads, because of the energy dissipation due to relative slip between constituent components. Among several finite element formulations proposed in the last years, the recent mixed formulation proposed by the authors could accommodate the slip discontinuity across the element nodes. In this paper this approach is evaluated with the study of the monotonic and cyclic response of a cantilever reinforced concrete column. The first load case showcases the unique capability of the mixed formulation to estimate the fixed-end rotation at the base of the cantilever column. The second load case demonstrates the accuracy of the mixed formulation in the representation of experimental measurements. The examples reveal that the mixed formulation has great potential in simulating composite structures under extreme loadings demonstrating excellent accuracy for the representation of the global as well as the local response.