Corrosion of steel embedded in mortar and concrete under different electrolytic accelerated corrosion methods

An efficient accelerated corrosion test method is the foundation for experimental investigation of corrosion behaviors of reinforcing steel embedded in mortar and concrete. In this work, the electrochemical mechanisms of four typical electrolytic accelerated corrosion methods (EACMs) currently adopted by numerous researchers are analyzed and compared, including embedded auxiliary electrode method, soaking method, part soaking method, and surface coating method. Based on the electrochemical mechanism, a numerical model for predicting the distribution of rust layers around steel rebar under EACMs is established. The parameters influencing the electrolytic accelerated corrosion (e.g. position of electrodes for embedded auxiliary electrode method, the electrolyte solution level for other methods) are investigated. It is concluded that the distribution profiles of rust layer vary with the EACMs adopted; by controlling and optimizing the critical parameters of EACMs, non-uniform distribution pattern of rust around rebar that is similar to that by natural corrosion can be induced in a short time. (C) 2020 Elsevier Ltd. All rights reserved.