pozzolanic cement

cement

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July 23, 2026

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Pozzolanic cement is a type of hydraulic cement that utilizes finely divided siliceous or aluminous materials. These materials react chemically with slaked lime in the presence of moisture to create a strong, slow-hardening cement. The Romans perfected this type of cement, traditionally made by grinding volcanic material (pozzolan) with powdered hydrated lime.12

This cement was crucial for the strength of Roman mortar and concrete used in structures like bridges and buildings. The term "pozzolana" or "pozzolan" refers to either the cement itself or any finely divided aluminosilicate that reacts with lime and water to form cementitious compounds. Modern pozzolanic cements are typically mixtures of portland cement and a pozzolanic material, which can be natural (like volcanic ash) or artificial (like fly ash).234

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concrete
…continued to be the primary pozzolanic, or cement-forming, agent until the early 1800s. In 1824 an English inventor, Joseph Aspdin, burned and ground together a mixture of limestone and clay. This mixture, called portland cement, has remained the dominant cementing agent used in concrete production.
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…continued to be the primary pozzolanic, or cement-forming, agent until the early 1800s. In 1824 an English inventor, Joseph Aspdin, burned and ground together a mixture of limestone and clay. This mixture, called portland cement, has remained the dominant cementing agent used in concrete production.
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cement
Slag cements
Pozzolanic cements are mixtures of portland cement and a pozzolanic material that may be either natural or artificial. The natural pozzolanas are mainly materials of volcanic origin but include some diatomaceous earths. Artificial materials include fly ash, burned clays, and shales. Pozzolanas are materials that,…
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Pozzolanic cements are mixtures of portland cement and a pozzolanic material that may be either natural or artificial. The natural pozzolanas are mainly materials of volcanic origin but include some diatomaceous earths. Artificial materials include fly ash, burned clays, and shales. Pozzolanas are materials that,…
Read More