Laboratory evaluation of mechanical properties and noise absorption in magnetite-enhanced concrete for pavement applications

This paper aims to evaluate the effects of incorporating magnetite as an aggregate in concrete mixtures and as a partial replacement for Portland cement in standard mortar mixtures, focusing on performance and mechanical properties. Noise pollution from cement concrete pavements has become a significant concern for residents, making it a priority to implement effective measures to reduce traffic noise pollution. The primary goal of this research is to explore the relationship between mixture design variables with magnetite aggregates as a partial replacement for Portland cement in concrete pavement and the mixture's acoustic performance. Samples with 0, 10, 20, 30, 40, and 50 % replacement of aggregates with magnetite sand were prepared initially. Subsequently, Portland cement was replaced with 0, 1, 2, 3.5, 5, 7.5, 10, 15, and 20 % magnetite concentrate powder in standard mortar. Routine tests, such as slump, density, and flow table, were conducted on fresh concrete and mortar. Additionally, compressive strength, flexural strength, water absorption, electrical resistance, and impedance tube tests were performed on the concrete and mortar mixes. The impedance tube measurements demonstrated an increase in the sound absorption coefficient for concrete incorporating magnetite compared to the reference concrete. Among the tested concrete samples, the one containing 50 % magnetite as aggregate exhibited the highest sound absorption coefficient, reaching a maximum value of 0.1 within the frequency range of 315–400 Hz. This value was 2.5 times higher than the maximum sound absorption coefficient of the reference concrete.