Title:
Study of Electrochemical Rehabilitation of Chloride Contaminated Reinforced Concrete
Author(s):
K. Ishibashi, M. Kanda, Y. Furukawa, and T. Mihara
Publication:
Symposium Paper
Volume:
193
Issue:
Appears on pages(s):
139-150
Keywords:
cement; concrete; deterioration; hydration; rehabilitation; silicate
DOI:
10.14359/5818
Date:
8/1/2000
Abstract:
Recently, various electrochemical rehabilitation methods, such as desalination, re- alkalization and electro-deposition, have been developed in order to recover deteriorated concrete due to chloride ion or carbonation, and to improve the durability of reinforced concrete structures. However, there is not sufficient information about the influence of these methods on hydration reaction of cement matrix. From this point of view, the authors studied about desalination; relationship between cumulative current and removal of chloride ion, and influence of desalination treatment on hydration reaction of cement matrix with the aid of solid-state 29Si-NMR spectroscopy. The results show that the amount of chloride removed and the charge efficiency depend on the initial chloride content and cumulative current. From 29Si-NMR analysis of specimens which were stored for 4 years after desalination treatment under condition of 20°C and 60%R.H., the ratio of higher-condensed silicates varied depending on the cumulative current during desalination. It became obvious that desalination process influences hydration re cement silicates. action of