Effect of the marble fineness on the rheological characteristics of concrete

Abstract

The objective of this experimental work is to study the effect of the marble fineness on the rheological behavior of ordinary concrete at fresh and hardened states. Five (5) types of concrete were made: a control concrete with cement CEMI/42.5 and four other concretes where CEMI cement was partially replaced by marble powder at the rate of 5% and 10% with two Blaine finesses: 2400cm²/g and 7000cm²/g. The rheological parameters of the concrete were measured using the ICAR rheometer and the compressive and flexural strengths were determined on 10x10x10cm³ cubic specimens and on 7x7x28cm³ prisms, respectively at different times (3, 7, 28 and 60 days). The results obtained showed that the optimum in marble powder should be equal to 5% and without a high grinding (2400cm²/g); the concrete retains its rheological characteristics at fresh state and its mechanical properties at hardened state. For a replacement rate of 10% and a fineness of 7000cm²/g, the yield stress of the concrete increases considerably, although the mechanical strengths are important.