Multiphysical Coupling Analysis of the Transition Zone Behaviour in Corroded Reinforced Concrete Structures

Corrosion is a multiphysical process that takes place at the steel/electrolyte interface causing a series of interconnected coupled phenomena. For reinforced concrete structures, electrochemical reactions are controlled by environmental, physical, and mechanical factors related to concrete and steel. The electrochemical nature of corrosion can manifest by cracking, local spalling, presence of rust, sectional loss of alternating stability, and serviceability of infrastructures. The different nature of the constituent materials creating the structure’s system causes an interface problem in the interaction zone considered as the transition zone (ITZ). This work aims at studying the transition zone problem of a concrete beam reinforced with a single steel bar subjected to corrosion. The objective is to assess the beam system’s durability and behaviour over time under the influence of corrosion, first with mechanical analysis and then by combining corrosion into a mechano-electrochemical study using coupling techniques to model the steel/concrete transition zone (ITZ). The development of this model has allowed us to better understand the importance of modelling the transition zone in the assessment of multi-material system interactions, as well as the contribution of coupling techniques in numerical modelling of corroded infrastructures.