Hydration and Microstructural Properties of Cement Paste Containing Nano and Microsilica

Abstract

<jats:p>The influence of nano-and microsilica addition on ordinary Portland cement (OPC) pastes has been studied in terms of hydration and microstructural properties. Three different combinations of nano-and microsilica mixes were used. A constant water-binder ratio of 0.35 was maintained throughout the experiment. All samples were tested for initial and final setting time and compressive strengths were determined at the age of 3, 7, 28, and 90 days of hydration. The hydration products were examined by SDT and XRD analysis at various curing ages. The inclusion of nano-and microsilica reduced the initial and final setting time significantly, increased the compressive strength of hardened cement paste after 7 days of hydration, and reduced the amount of calcium hydroxide in the hardened paste compared to mixes without these nanoparticles. </jats:p>

XRD analysis for hydration products of different lime-pozzolan systems

“…Two samples from mixes Lime-Silica fume-Fly ash and Lime-Metakaolin mixtures at the age of 90 days to study the difference in hydration products when using different binders. [5] Bottrill [9] and Bernd [10]. [11].…”

“…X-Ray Diffraction, XRD, is a technique used to determine the mineral properties of a crystalline solid. When a crystalline solid is exposed to X-Rays of a particular wavelength, layers of atoms diffract and produce a pattern of peaks, which characterize the minerals present in the material [5]. Powder XRD has numerous advantages like non-destructive nature, high sensitivity, reliability, easy sample preparation, system is user friendly, operational procedure is convenient, easy data interpretation that could be used for both qualitative and quantitative analysis, in wide range of applications.…”