Evaluation of Thermal Properties of Early-Age Concrete Containing Fly Ash

Abstract

Fly ash, a by-product of burning pulverized coal in electrical generating stations, is used as a supplementary pozzolanic material in the production of Portland cement concrete. It improves, e.g., workability of a concrete mixture, suppresses bleeding, reduces the rate of production of hydration heat and delays finishing operations. Consequently experimental research, theoretical analysis, incorporating available microstructural data, and efficient numerical simulations are needed to understand the influence of early-age curing on later macroscopic mechanical, thermal, etc. material properties. This paper presents a proper experimental and computational approach to the evaluation of time-variable thermal characteristics of a hardening mixture, based on the weak formulation of the evolution problem and on the least squares optimization. Results of such types are necessary for reliable prediction of behaviour, performance and durability of buildings and engineering structures.