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Why do high-slag cements have greater resistance to chemical attack?

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Cement The cement-making process, from crushing and grinding of raw materials, through roasting of the ground and mixed ingredients, to final cooling and storing of the finished product.

High-slag cements, such as portland blast-furnace cement, exhibit greater resistance to chemical attack primarily due to their specific chemical composition compared to standard portland cement.1

These cements are characterized by a lower lime content and a higher concentration of silica and alumina. In standard portland cement, the hydration process releases calcium hydroxide, which is vulnerable to chemical degradation. By incorporating slag, which contains reactive silica and alumina, the cement chemistry is altered to mitigate these vulnerabilities.123

Furthermore, the alumina compounds present in cement are generally the most susceptible to attack from agents like sulfate salts or seawater. The specific formulation of high-slag cements helps improve durability against these environmental factors, providing enhanced protection against many forms of chemical deterioration.31