Quick Determination of Freeze–Thaw Durability of Concrete Aggregates Using the Indiana Department of Transportation Hydraulic Fracture Test Equipment

Abstract

The freeze–thaw durability of carbonate aggregates can vary greatly, from durable to highly susceptible to freeze–thaw distress. Using nondurable aggregate in concrete pavement exposed to freeze–thaw cycles may lead to serious distress and greatly decrease the pavement's service life. The testing needed to identify freeze–thaw durable aggregates can take several months to complete. The main objective of this study was to develop a reliable, quick test method for determining the freeze–thaw resistance of carbonate aggregates quarried in Indiana by using the hydraulic fracture test (HFT) equipment. Aggregate samples collected from 18 quarried carbonate sources that represented a range of freeze–thaw performance were subjected to HFT with the modified Indiana Department of Transportation (Indiana DOT) HFT equipment. Aggregates from the same sources were also used to produce concrete beams that were subjected to the Indiana DOT-modified AASHTO T161-B freeze–thaw test. This test evaluated the dilation of beams exposed to freeze–thaw cycles. The experimental data were analyzed statistically, and a linear regression model was developed to predict the average percent dilation of freeze–thaw test beams using parameters obtained from HFT results. Comparing the predicted dilations to the measured dilations gave an adjusted R2 value of .85 and indicated that the model has a high degree of certainty. The modified Indiana DOT HFT equipment, refined test procedures, and data analysis developed during this study are recommended as screening tools for predicting AASHTO T161–ASTM C666 test results in 8 days. However, further testing is necessary to refine and validate the model before it is fully implemented as an accepted standard.