Performance Of Concrete Containing HighVolume Coal Fly Ash - Green Concrete

Concrete is usually the most common element in a building and over the years, many solutions were developed in order to improve its qualities. We conducted a comparison between ordinary Portland cement concrete and high volume coal fly ash concrete, with the fly ash used as a substitute for the cement. Generally accepted, the total binder in a green concrete is composed of 50% cement and 50% fly ash, which is less than 200 kg/m in our case (P. Kumar Mehta – High Performance, high-volume fly ash concrete for sustainable development. University of California, Berkeley, USA). We investigated concrete mixes containing 40% and 50% fly ash as partial replacements of the cement. A C20/25 class concrete was tested at 7, 28, 90 and 365 days of age for: compressive and tensile strength, modulus of elasticity, freeze thaw resistance, water permeability, and shrinkage and bond strength. We found that concrete made with fly ash is a good choice for a medium concrete class with increased durability properties.