Assessing the Variability of Laboratory Test Procedures for Predicting Concrete Field Performance Against Alkali-Aggregate Reaction (AAR)

Alkali aggregate reaction (AAR) affected structures show reduced serviceability and premature distress in over 50 countries worldwide. Several approaches have been proposed to evaluate the reactivity potential of aggregates by varying the conditions known to trigger and sustain the reaction. Among them, the most popular methods are the accelerated mortar bar test (AMBT) and the concrete prism test (CPT). Nevertheless, exposed site data has increased considerably in recent years, showing significant discrepancies between laboratory results and actual concrete field performance. In this study, the variability of laboratory performance methods was explored indicating low and moderate accuracy in predicting field performance for AMBT and CPT, respectively. While it provides initial insights on the recalibration of the methods outcomes, advanced analysis methods are suggested to enhance such predictions. Therefore, such measures can enhance the safety of concrete infrastructures by accelerating the identification of risks associated with incorporating AAR-prone aggregates into new structures.