Assessment of Damage to Metakaolin-blended Cementitious Material at Elevated Temperatures Based on Electrochemical Impedance Spectroscopy Technique

Abstract

Electrochemical impedance spectroscopy (EIS) was used to examine the electrical properties of metakaolin (MK) cement-based materials at elevated temperatures. We utilized a new equivalent circuit to investigate the EIS results of cementitious materials blended with MK at these temperatures. A new evaluation method to high temperature damage is proposed. The findings show that both elevated temperatures and MK contents in cement mortar can impact the impedance spectra’s form properties. However, the residual compressive strength of the MK-blended cementitious material at elevated temperatures does not improve with the addition of MK. A quantitative relationship between the electrochemical parameters of the new equivalent circuit and the residual compressive strength is determined. The degree of high-temperature damage to cementitious materials can be evaluated based on these electrochemical parameters, providing a new approach for evaluating the high-temperature damage of MK-blend cementitious materials.

RIGHTS & PERMISSIONS

Wuhan University of Technology and Springer-Verlag GmbH Germany, Part of Springer Nature