Thermogravimetric analysis of limestone aggregates for portland cement concrete

Durability of coarse aggregate has a major impact on the durability of portland cement concrete. Over the past years, there has been an increasing interest in developing and improving test techniques that provide a more accurate durability assessment, which ultimately leads to a better prediction of pavement performance. Thermogravimetric analysis is a relatively rapid technique that has shown good potential for use in the analysis of carbonate aggregates. Thermogravimetric technique (TG) was used to analyze 31 limestone aggregates. The specimens were heated to temperatures above 1000 degrees C using two rates of temperature increase. The weight loss and the change in weight loss as a function of temperature were recorded. Results show a correlation between the slope before calcite transition and some durability aspects of limestone. Moreover, the TG output can be used to calculate the percent acid insoluble (AI) and the pavement vulnerability factor (PVF). Therefore, TG may be considered as a rapid method for AI and PVF determination.