Electrochemical impedance spectroscopy (EIS) used to evaluate influence of different external pressures, curing ages and self-healing environments on the self-healing behavior of engineered cementitious composites (ECC)

During the past decade years, engineered cementitious composites (ECC) as a new kind of fiber-reinforced cementitious materials has been a hot topic, due to excellent tensile strain and multiple-cracking ability. In this paper, the main objective is to use electrochemical impedance spectroscopy (EIS) with a novel equivalent circuit (EC) model to study the influence of external pressure, curing time and self-healing environment on the self-healing behavior of ECC. The experimental results show that EIS of ECC changes depending on the self-healing behaviors which affects on different external pressures, curing times and environments, respectively. The resistance associated with the ion transport process gradually increases along with the self-healing process. In addition, the relationship between the parameter Rct value and the self-healing cycles is also analyzed. More important, EIS as a non-destructive method is used to access the self-healing behavior of ECC, and the reliability of the new equivalent circuit model is investigated across the entire self-healing process. The critical insight are emphasized to guide the future research on the development of self-healing ECC which can assess the effect of self-healing behavior of ECC exposed to different factors by the electrochemical measurement.