Title:
Measuring Chloride Concentrations for Various Cement-Based Materials Systems
Author(s):
Ceki Halmen and David Trejo
Publication:
Materials Journal
Volume:
104
Issue:
6
Appears on pages(s):
567-574
Keywords:
chloride concentration; durability; grout
DOI:
10.14359/18960
Date:
11/1/2007
Abstract:
Measurement of the chloride concentration of cement-based materials is an important issue because chlorides are known to cause corrosion of metals embedded in these cement-based materials. Chloride concentrations of grout, low-strength flowable cement-based mixtures, and normal-strength concrete samples were measured using the standard potentiometric titration method (ASTM C 114) and a faster and less expensive method developed under the Strategic Highway Research Program (SHRP). The rapid method was used with 1.5 and 3.0 g (0.053 and 0.106 oz) samples. Results indicate that, for grout and normal-strength concrete samples, both methods are very well correlated for both 1.5 and 3.0 g (0.053 and 0.106 oz) samples. Although the results of both methods were also very well correlated for low-strength cement-based mixture samples, findings indicate that the slope of the linear regression equation to estimate the results of the standard ASTM method was significantly different and less than unity and that the intercept was not statistically significantly different from zero. Results of this study indicate that the use of the faster method developed as part of the SHRP can result in accurate and reliable estimates for the chloride concentration of various cement-based material systems.