Evaluation on the acidification damage of the external anode mortar induced by impressed current cathodic protection

摘要

Impressed current cathodic protection (ICCP) can cause acidification damage in the external anode mortar and influence its durability and service life. The caused acidification effect was only experimentally investigated in the simulated pore solution and the dissolution of hydration product during the process was not considered. In this study, the acidification damage induced by ICCP treatment was investigated in the external anode mortar. The results indicated that the applied current reduced the corrosion resistance of Ti mesh embedded in the mortar; this negative effect was more pronounced in the presence of chlorides. When the external current was applied, Ca(OH)(2) content at Ti mesh/secondary mortar interface decreased, leading to a lower Ca/Si ratio and increased porosity of the mortar matrix. Based on the experiment results, the acidification damage occurred at Ti mesh/secondary mortar interface was quantitatively evaluated in terms of the electric charge quantity during the treatment. (C) 2019 Elsevier Ltd. All rights reserved.