Influence of Microwave Curing on the Compressive Strength of Cement Based Mortars

Abstract

Cement based concretes are the most widely used materials in the construction industry. A higher rate of strength development in concrete can greatly facilitates and accelerates several important processes in the construction industry. Accelerated strength development in concrete can be reached by different methods. Recently and on varying scales, alternative techniques for rapid heating, drying and curing have been experimented for cement-based materials. One of those is the microwave heating technique, which is the technique of our concern in that research.

An experimental program was conducted to study the effect of microwave curing on the mechanical properties of based cement mortar specimens compared with a number of different curing regimes, The effect of adding mineral admixtures (silica fume, fly ash), The effect of changing cement to sand ratio (CIS), the effect of changing cement type, The effect of adding poly propylene fibers, and the effect of changing delay time (time before specimens are subjected to microwave) were the main factors studied in that research.

Experimental results revealed that, the presence of silica fume enhanced early strength gain significantly for all mixtures especially for the microwave/water cured specimens. For specimens cured at day 7 from mixing, microwave/water curing is beneficial for achieving high early strengths for most of mixtures presented. Furnace/water curing is required for achieving high late strengths for most of mixtures presented.