Packing density and reactivity of waste quarry dust as a supplementary cementitious material

In response to concerns about global warming, the construction industry is actively seeking to reduce CO2 emissions linked with the production and use of Ordinary Portland Cement (PC). While the use of conventional supplementary cementitious materials (SCMs) can help reduce the amount of PC used in construction, this well-established practice faces challenges due to evolving energy policies and scarcity of materials. This study explores the potential of waste quarry dust as a sustainable alternative, aiming to recycle waste and minimize the environmental impact of construction.
The research focuses on utilizing milled waste quarry dust in cementitious mixtures, exploring its role as a filler or SCM. Investigating particles ranging from 0.24µm to 250µm, the study aims to understand their impact on packing density, formation of cement hydration products, and reactivity in cementitious mixtures.
The research enhances the theoretical 2-parameter packing model, incorporating particle size distribution for more accurate predictions of blended cement density. Findings indicate that milled quarry dust enhances early-stage hydration and contributing to new hydrate development in the cement matrix. The study also explores the absorption characteristics of cement-based composites with quarry dust, revealing a 10% increase in water absorption and a 20% rise in pore phase area fractions, indicative of altered material porosity. Findings also include the predictable nature of capillary absorption across different QD types and the identification of factors such as hydration heat and pore structure influencing absorption rates. Overall, this research provides experimental evidence that supports the use of quarry dust as a viable and sustainable alternative to cement, paving the way for more environmentally friendly construction practices.