scope:

This report provides a review of the state-of-the-art use of raw or processed natural pozzolans in concrete and an overview of the properties of natural pozzolans and their proper use in the production of hydraulic-cement concrete. Natural pozzolans mixed with lime were used in concrete construction long before the invention of portland cement because of their contribution to the strength of concrete and mortar. Today, natural pozzolans are used with portland cement not only for strength, but also for economy and beneficial modification of certain properties of fresh and hardened portland-cement concrete.