3D nonlinear finite element simulation of RC beams corroding under service loads

Abstract

ABSTRACT In the present study, a 3D nonlinear finite element (FE) model has been developed to simulate reinforcement corrosion in RC beams under sustained load. The corrosion effects were modelled as bond deterioration at the rebar-concrete interface, damage in cover concrete and mechanical degradation of corroded rebars. A simplified temperature field-based methodology was proposed in the commercial program ABAQUS to simulate the evolution of corrosion degradation while a sustained load is maintained in the beam. The FE model was validated using available experimental results in terms of cracking behaviour and load-deflection response and found to be in good agreement. Parametric investigations were carried out to analyse the performance of beams under simultaneous corrosion and sustained loads. The findings demonstrated that pitting corrosion under simultaneous loading conditions can significantly compromise a beam’s structural integrity. Specifically, a scenario with 20% mass loss and 60% sustained load resulted in a 33.3% increase in concrete strain and a significant increase of 738% in the tensile steel strain leading to yielding. Furthermore, the influence of load and corrosion sequence on the behaviour of the beam was assessed by comparing its response when corroded under sustained load with a beam corroded and subsequently loaded.