Utilization of Perlite Rock in Blended Cement-Part I: Physicomechanical Properties

Abstract

The influence of 0, 5, 15 and 25 wt. % natural perlite (PT) on the specific properties of Ordinary (OPC) and Slag (SPC) Portland cements was studied. The results showed that the water of consistency was increased with the increase of PT content and also the setting times were elongated, but they were higher with SPC than with OPC. The combined water content, bulk density and compressive strength were increased with curing time up to 28 days and then became nearly stable at 90 days, but only increased with PT content up to 15 wt. % and then decreased. The apparent porosity decreased with curing time, but only decreased up to 15 wt. % PT and then increased. The free lime content of the OPC pastes increased gradually up to 90 days, while those of SPC pastes and those mixed with PT decreased gradually. According to the results of the free lime, the PT possessed high pozzolanic activity as confirmed by the FT-IR spectra and SEM images. The addition of higher amounts of PT (25 wt. %) has affected adversely on all properties of both cements.