Title: A Method toTest the Alkali Reactivity of Siliceous Aggregates: Infrared Spectroscopy

Author(s): Alessandro Bachiorrini

Publication: Symposium Paper

Volume: 100

Issue:

Appears on pages(s): 1821-1832

Keywords: aggregates; alkali-aggregate reactions; evaluation; infrared spectroscopy; siliceous aggregates; Materials Research

DOI: 10.14359/2235

Date: 4/1/1987

Abstract:
The alkali reactivity of siliceous aggregates depends on the microstructural disorder of the aggregate, plus further factors that can increase the phenomenon. The use of infrared (IR) spectroscopy to quantify this disorder is suggested. A simple graphic elaboration of an IR spectrum allows one to determine a disorder coefficient Cd. This allows one to compare rapidly and with assurance the different degrees of disorder for a number of siliceous minerals. Using as reference some samples whose alkali reactivity has been determined in a different way, a Cd limit value has been fixed. For this Cd value, the disorder is such as to raise no doubt about the aggregate susceptibility to alkali-silica reaction. This method can also be applied to calcareous aggregates that include siliceous minerals; if these inclusions are more than 10 percent, it is possible to use the sample without exclusion of the calcareous matrix phase.