Rapid estimation of natural pozzolan dosages for mitigating ASR using the innovative chemical screening tool (CST)

Our research aimed to validate a previously developed chemical screening tool (CST) for estimating the dosage of natural pozzolans (NPs) in mitigating alkali-silica reaction (ASR) in concrete. Experimental evaluation showed that NPs contribute low soluble alkalis into pore solution despite their high bulk alkali contents. Consequently, CST predicted a 28-30 % dosage of NPs to mitigate ASR for a highly reactive fine aggregate satisfying concrete pore solution alkalinity <= aggregate threshold alkalinity criterion. CST-based estimations were favorably validated through ASR tests. Overall, the effectiveness of CST for rapid estimation of NP dosages for ASR mitigation with acceptable accuracy was successfully validated.