How Moisture Cracks Alkali-Reactive Concrete

Alkali-aggregate reaction in concrete can weaken a structure when siliceous minerals in the aggregate react with alkaline hydroxides from cement. The reaction makes an alkali-silica gel, which pulls in water and swells. As the gel expands inside the rigid cement paste, it creates pressure that can crack and disrupt the concr...

Aggregates naturally contain siliceous minerals that react with the alkaline hydroxides from cement alkalis.

The alkali-silica gel formed attracts water and swells, which is constrained by the cement paste around it, leading to internal pressure, causing the cement paste to crack and disrupt, evidenced by expansion.

Expansion is pa...