Title: SEM Analysis of the Paste-Aggregate Interface in Concrete Containing Silica Fume

Author(s): J.B.L. Liborio, I.J. da Silva, and A.B. de Melo

Publication: Symposium Paper

Volume: 207

Issue:

Appears on pages(s): 245-262

Keywords: C-S-H; calcium hydroxide (CH); microstructure; paste-aggregate interface; scanning electron microscopy; silica fume

DOI: 10.14359/12394

Date: 10/7/2002

Abstract:
In this study, an analysis of the region of the paste-aggregate interface is carried out by means of scanning electron microscopy. A microanalysis of the Ca/Si ratio in and outside this region is also performed. The images suggest that the presence of silic;r fume produces a more homogeneous interface and outlines the synergetic effect of silica fume and slag, decreasing the CH quantity in concrete or changing the crystals morphology. This influences the development of concrete strength, since the absence of the transition zone compressing the CH crystals facilitates the formation of a better connection of the paste-aggregate system.