Proposing a New Approach for Qualification of Natural Pozzolans

Recognizing natural pozzolans and their qualities is one of the most important dilemmas in the field of cement and concrete. Although di erent methods have been published towards this aim, research shows some anomalies between the judgments of these methods. This paper aims to compare evaluation methods of natural pozzolans by considering their performance in concrete as a decision criterion in order to develop a guideline for their quali cation. Therefore, rstly, the main available methods are described. Then, the pozzolanic activity of natural pozzolans is investigated using these methods and compared with the performance in concrete. Finally, a guideline is proposed, based on the discussed methods.