Dhers, S, Freimut, D, Martic, Z & Salter, R 2024, 'Admixture impact on rheological properties of a calcined clay binder for cemented paste backfill', in AB Fourie & D Reid (eds), Paste 2024: Proceedings of the 26th International Conference on Paste, Thickened and Filtered Tailings, Australian Centre for Geomechanics, Perth, pp. 131-138, https://doi.org/10.36487/ACG_repo/2455_09
(https://papers.acg.uwa.edu.au/p/2455_09_Dhers/)
Abstract: Calcined clays appear to be one of the most promising supplementary cementitious materials to reduce the CO2 footprint of cement, in particular the limestone calcined clay combination known as limestone calcined clay cement (LC3). New and improved admixtures with tailored properties are necessary to ensure a broad implementation of LC3 in the mining industry, to reach net zero. This study investigates the time-dependent rheological behaviour of cemented paste backfill (CPB) that contains calcined clay as a binder, using three admixtures, amongst which one is part of the Intelligent Cluster System (ICS) for low-clinker concrete technology. Yield stress and plastic viscosity have been reported and highlights the impact of the admixtures. A cradle-to-gate lifecycle assessment comparison between CEM I and the LC3-35 binder (LC3-35, containing 40% calcined clay, 20% limestone) is also detailed in this work. This study evidences the readiness of calcined clay binders for CPB, using the adequate high-performing admixtures. 

Keywords: cemented paste backfill, superplasticiser, calcined clay, LC3, rheology, compressive strength