Title:
Application of Rapid Chloride Permeability Test to Evaluate the Chloride-Ion Penetration Into Concrete
Author(s):
K. Torii, T. Sasatani and M. Kawamura
Publication:
Symposium Paper
Volume:
170
Issue:
Appears on pages(s):
421-436
Keywords:
Chlorides; electrical properties; environments; exposure; mineral
admixtures; permeability; tests
DOI:
10.14359/6834
Date:
7/1/1997
Abstract:
This paper presents the data on the application of the Rapid Chloride Permeability Test (RCPT) to the evaluation of chloride-ion penetration into the concretes with and without mineral admixtures. OPC concretes, fly ash 30 % concretes, blast-furnace slag 50 % concretes and silica fume 10 % concretes were prepared. The concrete blocks, 240 by 240 by 210 mm, were initially cured for 28 days, and then exposed to the three different environments : in water at 20 oC, in dry room at 20 oC and 60 % R.H. and on the roof of a building at Kanazawa University. After 5 years of exposure, five cores of 50 or 100 mm in diameter were taken from each concrete block. Physical and chemical properties of the surface and the synopsisnterior of the concretes were investigated. Changes in the chloride permeability of the concrete with the depth from the exposed surface were determined using the RCPT. Both the electrical resistivity test and the measurement of chloride-ion penetration into the concrete were also carried out. The results of the RCPT showed that both the surface and the interior of the concretes with mineral admixtures were much less permeable to chloride ions than the corresponding OPC concretes under all curing and environmental conditions. Furthermore, it was found that there was a good correlation between the charge passed in the RCPT, the initial direct current and the electrical resistivity, which also correlated well with the chloride-ion penetration depth into the specimens after the RCPT. It was concluded that the charge passed in the RCPT was an effective indicator to evaluate the chloride permeability of a large variety of concrete mixtures.