Overall assessment of Alkali-Aggregate Reaction (AAR) in concretes presenting different strengths and incorporating a wide range of reactive aggregate types and natures

Abstract

It has been suggested that the Stiffness Damage Test (SDT) and the Damage Rating Index (DRI), mechanical and microscopic tools respectively, can reliably assess the condition of concrete affected by Alkali-Aggregate Reaction (AAR). However, a multi-level characterization of AAR damage through the coupling of the prior tools has never been evaluated so far. This paper presents the overall assessment of twenty concrete mixtures presenting different strengths and incorporating a wide range of aggregate types/natures. Evaluations on both AAR crack development and its influence on the mechanical properties of affected concrete are performed over a multi-level point of view. Results show that strong data envelopes are obtained from each of the test procedures, correlating various critical microscopic and mechanical output parameters with AAR expansion level. Moreover, such assessments allowed the development of comprehensive quantitative data which enables a better understanding/prediction of the material's properties degradation as a function of AAR development.