Lavallee, J & Van de Sande, J 2024, 'Efficiency of accelerator atomisation in mechanised applications of sprayed concrete', in P Andrieux & D Cumming-Potvin (eds), Deep Mining 2024: Proceedings of the 10th International Conference on Deep and High Stress Mining, Australian Centre for Geomechanics, Perth, pp. 643-656, https://doi.org/10.36487/ACG_repo/2465_39
(https://papers.acg.uwa.edu.au/p/2465_39_Van_de_Sande/)
Abstract: Due to the numerous complexities involved with sprayed concrete operations, determining methods for savings and efficiencies that provide several benefits throughout the value chain can allow for product viability across a wider range of use cases. Mechanised sprayed concrete is essential for a wide range of construction activities, with the leading sectors being civil tunnelling, slope stabilisation, and mining.
The operational costs associated with sprayed concrete can become significant due to the wide range of requirements involved, including batched material components, admixture chemicals, re-entry or set times, rebound, etc. Therefore, finding solutions to provide savings and efficiencies while improving the final quality of the process is crucial to improving operations and making the process more technically  economically viable to an expanded range of use cases. Additionally, solutions that allow for a reduction in the carbon footprint associated with sprayed concrete, as well as improving operations, make the prospect enormously more valuable. This paper discusses how a system designed to reduce the amount of set accelerator chemical consumed by using an efficient accelerant dispersal method can provide improved strength development characteristics while also providing savings and efficiencies throughout the process. Key areas addressed include how atomisation of aluminium–sulphate-based accelerator impacts initial early-age strength development while allowing for a reduction in dosage or consumption of accelerator, increased strength development at reduced time intervals that can allow for decreased re-entry times, and effectively optimising sprayed concrete mix designs.
Utilising a passive solution that does not require additional procedures or changes to the sprayed concrete process administers numerous benefits that impact initial and final strengths, as well as operational efficiencies and cost improvements, and adds value throughout the process, is a true leap forward for the sprayed concrete industry.

Keywords: equipment technology, strength generation, low-carbon solutions, quality control, accelerator, savings, cost reduction