Utilisation of waste marble dust for improved durability and cost efficiency of pozzolanic concrete

This study demonstrates that the incorporation of waste marble dust to pozzolanic concrete improves the long-term mechanical properties and durability characteristics. A comprehensive study utilising specimens containing a cement and silica fume binder were manufactured with incremental levels of marble dust fine aggregate. Important physical properties including compressive strength, water penetration depth, porosity, resistance to sulphate attack and resistance to freeze/thaw cycling were evaluated over a period of 1 year. Microstructural development attributed to cement hydration and pozzolanic reaction was imaged at 28 days and 1 year using scanning electron microscopy. The inclusion of marble dust greatly improved the salt crystallization and freeze and thaw resistance of the concrete over the long-term with only a small decrease in compressive strength observed. Importantly this highlights the beneficial properties of marble dust on durability. Additional advantages were shown through cost efficiency analysis which revealed that utilisation of marble dust and silica fume in concrete can reduce the embodied CO2 emissions improving the economic credentials and environmental impact. Marble dust not only improves the physical characteristics but also provides an environmentally friendly route for waste disposal and creation of a more