SIMULTANEOUS INFLUENCES OF MICROSILICA AND LIMESTONE POWDER ON PROPERTIES OF PORTLAND CEMENT PASTE

摘要

The purpose of this work is to study simultaneous influences of both microsilica and limestone powder, i.e. pozzolanicityand plasticity respectively, on important physicomechanical properties of fresh and hardened Portland cement paste.Different ternary mixes were prepared and studied by determining their relative workability, 7- and 50-day compressivestrengths, water absorption, bulk specific gravity, and volume of permeable pore space. The obtained results confirm that theplasticizing effect of limestone powder makes it possible to replace Portland cement by a proportioned mixture of microsilicaand limestone powder for improving the strength behavior at a constant W/C-ratio without any dispersing agent. It is alsopossible to produce ternary composite cements containing relatively high contents of microsilica and limestone powder withno considerable loss in both workability and compressive strength compared to plain Portland cement paste.