Influence of metakaolin and silica fume on the mechanical properties of high performance mortar

Abstract EN

This work include an activation of locally kaolin clay by thermal process, at different temperatures up to 800ºC and comparision between metakaolin (MK) and silica fume (SF) used as mineral admixtures in high performance mortar (HPM).

Cement was replaced with 10% MK or 10% SF.

Such mortar mixes were examined in density, absorption, compressive, flexural, tensile and bond strengths.

The results show that the calcination of 10% MK up to 750°C boost the strength activity index up to 148.5%.

However, such index is 80.25% due to 10% SF replacement.

Besides, the slant shear strength of HPM incorporated with 10% MK increased by about 88.7% higher than that of reference mix.

Whereas, the remarked percentage increase is 50% for HPM containing 10% SF.

The inclusion of 10% MK in mortar mix fosters the tensile strength by about 20.3% compared to reference mix.