Alkali-silica reaction (ASR) mitigation involves strategies to prevent or minimize the deleterious expansion and cracking in concrete caused by the reaction between alkaline cement paste and reactive silica in aggregates. Effective mitigation includes using low-alkali cement, incorporating supplementary cementitious materials, and controlling the moisture exposure of the concrete structure.

Alkali-silica Reaction Mitigation

The Alkali-Silica Reaction (ASR) is a chemical reaction that occurs in concrete between the alkaline pore solution and reactive silica found in certain aggregates, leading to the formation of a gel that expands upon absorbing water and causes cracking and deterioration of the concrete. This reaction is a significant concern in the durability and longevity of concrete structures, especially in environments with high moisture levels.

Alkali-Silica Reaction

ASR mitigation

Strategies to prevent expansion

Cracking in concrete

Alkaline cement paste

Reactive Silica

Reactive silica in aggregates

Low-alkali Cement

Supplementary cementitious materials (SCMs) are used in concrete to enhance its properties, such as strength, durability, and sustainability, by partially replacing Portland cement. These materials, including fly ash, slag, and silica fume, contribute to the reduction of carbon emissions associated with cement production and improve the performance of concrete in various environmental conditions.

Supplementary Cementitious Materials

Moisture exposure

Concrete structure

Concepts

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