Accelerated test for assessing the potential risk of alkali-silica reaction in concrete using an autoclave

Abstract

To rapidly assess the potential risk of alkali-silica reaction (ASR) in concrete, an accelerated test using an autoclave by adopting multi-cycle 80 °C steam warming at atmospheric pressure is proposed. The influence of autoclave steam warming temperature, cycles/duration, and alkali dosage on expansion of mortar bars and concrete prisms was evaluated. Mechanical properties of concrete under accelerated ASR test were investigated. Furthermore, SEM-EDS analysis confirmed ASR products and indicated that the expansion is caused by ASR. The expansion limits considered for classifying aggregates were discussed. The experimental results demonstrated that the period required for assessing the potential risk of ASR in concrete (dacite aggregate in this study) can be shortened to 37 days.