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How to Solve Alkali-Silica Reaction in Concrete Having Glass Sand Aggregates? (Part-1)

Dear reader, at first, we want to discuss about alkali-silica reaction in concrete. Now-a-days engineers are concerned with number of chemical reactions that produce effect on concrete. Of these most common is alkali silica reaction which defines chemical reaction between reactive silica in aggregates and alkalis present in cement.

Dear reader we have discussed about such reaction in our previous posts and more elaborate discussion are coming. Here we would like to include why is this reaction harmful for understanding our present topic about application of glass as aggregate?

Scanning under electron microscope of concrete section: Cracks due to ASR
Under this reaction a gel of alkali-silicate product is formed which can take place in following locations:

a. Within weak planes

b. Pores in aggregates

c. Over the surface of aggregates.

The gel have swelling property and when found water, results an increase in volume thus producing expansion resulting cracks and we have learnt how much deterioration can take place under cracks in concrete.

So our topic was about replacing natural aggregates with glass. Glasses are inspecting for applying in concrete as replacement of fine aggregates, coarse aggregates and as cement replacement for many years. But most of the experiments produced unsatisfactory yields due to alkali-silica reaction as discussed above.

Now some researchers are introducing some suppressors of alkali silica reaction (ASR) to mitigate such problem and achieved some satisfactory results. Dear reader we will learn all these suppressors and results against ASR in next part of this topic; please stay with us.

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