Influence of Curing Conditions on Lime-metakaolin Mortars

This study analyzed the influence of curing conditions on air lime mortars with two types of metakaolin which were used as partial substitutes for lime mass (10%). Flexural strength and compressive strength tests, as well as mineralogical composition ones by X-ray diffraction (XRD), were carried out in specimens after having been cured for 28 and 180 days indoors, at constant temperature and humidity, and outdoors, with no direct exposure to rain. Analyses of microstructure and chemical composition were conducted by scanning electron microscopy (SEM) and by energy-dispersive X-ray spectroscopy (EDS), respectively, in 180-day-old specimens, which were cured outdoors. Comparisons of results of the experimental analysis showed that substitutions were less efficient in environments with low relative humidity.