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[Dr. N. Subramanian]

I read the following question in Quora and found it interesting and hence including it here with my response from a paper.

Is there any possibility of leaching heavy metals from fly ash blended cement concrete, when using for water retaining structures?

It is a very good question. I am giving below the following reply, based on the paper  "Toxicity and environmental and economic performance of fly ash and recycled concrete aggregates use in concrete: A review" by Rawaz Kurda, José D. Silvestre, and Jorge de Brito, Heliyon, 2018, 4(4), 2018[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5968176/ ]  

The leaching metals of FA decrease when they are incorporated in concrete. This reduction of the heavy metals' leaching between the FA powder and FA concrete may be related to the cement's ability to solubilize/stabilize the concentration of heavy metals due to chemical retention processes that allow the incorporation of the elements in the cement matrix, and physical retention by encapsulation. However, this study still suggests avoiding the use of FA concrete for drinking water tank and architectural concrete applications.


Anyone who has used FA concrete in water retaining structures may respond to this posting