Influence of Brazilian fly ash fineness on the cementing efficiency factor, compressive strength and Young's modulus of concrete
Margareth da Silva Magalhães, Bruna Figueiredo Cezar, Pedro Rodrigues Lustosa
Abstract
This work investigates the cementing efficiency, determined by the k-value, of a Brazilian fly ash. The analyzed variables are the fly ash fineness and content, the water content in the mixtures and age of concrete. Further, the influence of the fineness of fly ash on the Young's modulus was also investigated. The results indicate that the k-values evaluated for Brazilian fly ash are higher than the one recommended by European standard for concrete, EN 206. Furthermore, k-value depends on fly ash content and decrease when the content in the mixture is raised. Water/binder ratio and hydration time significantly influence the k-value, too. The results also indicate an improvement of k-value and relationship between compressive strength, Young's modulus and the fly ash amount in the mixture with an increase in fly ash fineness. New relationships between compressive strength and water/effective cementitious materials ratio, considering the k-values, are proposed for fly ash-concretes.