A discussion of the paper 'Characteristics of pastes from a Portland cement containing different amounts of natural pozzolan' by Adnan Colak

摘要

The paper by Colak [1] examines the influence of natural pozzolan on the physical, mechanical and durability properties of blended Portland cement pastes. I like to celebrate the study on the use of natural pozzolans that are the more extended source of mineral admixtures in the developed countries. I agree with some parts of the paper, but I have some commentaries that I would like to point out. From the experimental procedure, it is understood that the author has used paste specimens to determine the compressive strength on cement, although it is not a usual practice in cement standard around the world (i.e., ASTM C 109, EN 196-1). In addition, the author has tested the specimens in wet and in dry conditions. To determine the compressive strength, the specimens should be saturated in water according to standard.