MICROSTRUCTURE AND DURABILITY OF MORTARS MODIFIED WITH MEDIUM ACTIVE BLAST FURNACE SLAG,

Ahmed HADJ SADOK, S. KENAI, L. COURARD, A. DARIMONT

Résumé


Abstract:
Mechanical characteristics and durability properties of blast furnace slag cement composites
largely depend on the hydraulic activity of the slag. In this paper, a Granulated Blast Furnace
Slag with a low reactivity index is used in modifying mortar composition. Microstructure and
durability of mixes containing 0%, 30% and 50% of slag as substitution to OPC are
respectively compared and analyzed. Water porosity, Mercury Intrusion Porosity and pore
size distribution are studied after 28, 90 and 360 days of wet curing. A qualitative
microstructure analysis of mortars is proposed with Scanning Electron Microscope (SEM).
The durability of mortar is evaluated through capillary water absorption and chloride
diffusion tests. The results indicate a finer porosity and lower water absorption for slag
mortars at old ages (90 and 360 days). Moreover, lower chloride diffusion for 50% blast
furnace slag substitution is observed.

Mots-clés


Environment; Mortar; Blast furnace slag; Hydraulic activity; Pore structure; Microstructure; Durability; Chloride diffusion

Texte intégral :

PDF