Acid Reactivity on Aggregates

[pelelo]

I am working on a Dam project in which fine and coarse filter layers will be placed.

The contractor, nearby the area, has a huge stockpile of rounded aggregates (from a river around the project). Engineering team decided to test aggregates, once they got crushed, in order to verify the Acid Reactivity percentage of the limestone portion.

According to results, there were more than 30 reactive particles (from a 20 grams sample), so these aggreates will not be allowed to be used as fine and coarse filter for the dam.

I was wondering, if anyone knows any reference which could provide an improvement of these aggregates to somehow reduce the acid reactivity level of the limestone portion. Probably by adding something.

Please let me know,

Thanks

 

[dik]

What is in contact with the aggregate that will create an acid background? Most limestone shows some degree of acid reaction... it's a consequence of the minerals that limestone is composed of.

Most concrete has a pH of 12 or so and is fairly alkaline... and most limestone works well with it. There are some aggregates that have an alkaline type of reaction; these don't normally work well.

Dik