Reliability of chemical index model in determining fly ash effectiveness against alkali-silica reaction induced by highly reactive glass aggregates

• Validation of Malvar and Lenke [1] chemical index model for recycled glass aggregate.
• Model revisions predict fly ash dosages necessary to control the alkali-silica reaction.
• Allows concrete material suppliers blueprint for implementation of glasscrete in the field.

This study investigates the ability of six fly ashes to control ASR (alkali-silica reaction) generated by recycled glass sand. Specifically, this study evaluates the chemical index model’s (Malvar and Lenke, 2006 [1]) capacity to accurately predict the fly ash dosage necessary to mitigate ASR. Results show the current model is conservative for low lime (CaO <10%) ashes (∼9% greater dosage than experimental results) and quite conservative for higher CaO (>10%) ashes (∼36% greater dosage than experimental results). Conclusions suggest revising model parameters can provide accurate predictions for low CaO ashes and moderately conservative predictions for higher CaO ashes.