Dear Lidia Trusilewicz

thanks for the answer. I read the following paper, for determining the pozzolanic activity (as per EN 196-5 standard).

Article Comparison of Test Methods to Assess Pozzolanic Activity

In this paper they have calculated %CaO removal/pozzolanicity from theoretical maximum [CaO]. Negative value for % CaO removal refers to non pozzolanic material.

My experiments are showing negative value for fly ash. My doubts are:

thanks for your time.

(I have attached few screenshots from the same paper as reference)

Regards

Saurabh Khandelwal