Seismic Modelling of Corroded Reinforced Concrete Columns

Abstract

Deterioration of seismic resistance of columns due to existing corrosion damage is investigated using advanced non-linear finite element simulation and analysis of a large database of tests with the objective to develop performance criteria for seismic evaluation and assessment. Current guidelines for structural seismic evaluation do not address how to account for the condition of the reinforcement. Incorporating the degree of bar corrosion in the evaluation procedures would complicate significantly the problem of seismic assessment. However, bar section loss, embrittlement, loss of material strength and interfacial bond, all affect the member’s residual mechanical properties, the hierarchy of failure modes and the consequences on seismic performance of complete structural components. In this work, simple modifications of existing nonlinear assessment procedures are proposed, in order to account for the effects of corrosion on seismic performance. Reduction factors of reinforcement stress–strain properties and column stiffness, strength and deformation capacity were calibrated to an assembled database of experimentally tested corroded columns, and were verified through advanced nonlinear finite element analysis, after modeling the effect of mass loss on material properties.