CHLORIDE ION CONCENTRATION ON THE DISCOLORATION
BOUNDARY PRODUCED BY SPRAYING AgNO3 SOLUTION
35th Our World in Concrete and Structures (OWICs) - 2010
Yusuke Aoki*, Kisarazu National College of Technology, Japan
Keiji Shimano, Kisarazu National College of Technology, Japan
Masashi Suzuki, Toden-Kogyo Co., Ltd., Japan
Chloride ion, AgNO3 solution spray method, Corrosion of steel
Experimental study on the chloride ion concentration (Cbw) in concrete at the
boundary of the colored zone by spraying of AgNO3 solution was carried out. In
ranges of water-cement ratio (W/C) and sand-coarse aggregate ratio (s/a) of normal
concrete, it is found that Cbw strongly depends on changes in W/C but hardly depends
on changes in s/a. At each W/C, Cbw and the limit chloride ion concentration for
corrosion initiation of steel in concrete (Clim) was compared. Then, Cbw and Clim was
found to become about the same for concretes with W/C range of 0.50~0.55.
However, Cbw was found to become higher than Clim for concrete with W/C of about
0.4, and become lower than Clim for concrete with W/C of about 0.6.