Alkali–silica reaction

High school (ages 12+)
Science & Technology

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/alkali-silica-reaction

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the primary reactants?Alkali hydroxides (from cement) and reactive silica (from aggregates)
2. What is alkali-silica reaction?It is a chemical process that happens inside concrete when the alkaline cement mixes with certain kinds of silica in the stones, causing damage over time.
3. Why does concrete crack because of ASR?The reaction makes a sticky gel that absorbs water and swells, pushing the concrete apart and creating cracks.

Pore Solution: The liquid phase within the pores of hardened cement paste, containing dissolved ions and alkalis.
Supplementary Cementitious Materials (SCMs): Materials like fly ash or silica fume added to concrete to improve its properties and reduce alkalinity.
Aggregate Reactivity: The tendency of aggregates to undergo deleterious chemical reactions, such as ASR, with cement paste.