Early age observations by SEM o f the changes to hardened cement paste

ABSTRACT. The changes to the micro-structure of hardened cement paste by the partial replacement with silica-fume at 5, 10 and 20% levels have been studied using Scanning Electron Microscopy (SEM). It was found that the silica-fume reduced the capillary void space by filling of the larger pores. Further, silica-fume provides additional hydration products which themselves contain a refined pore structure, thereby changing the pore size distribution of the paste.