Grant: Discovery Launch Supplement

Ontario's Ring of Fire region is one of the province's most promising mineral development opportunities, which could support the transition to a more sustainable global economy and meet Canada's net-zero goal by 2050. However, the potential impacts on the environment from mining in the Ring of Fire are substantial, specifically on the remote Northern communities living nearby, as mining generates a vast amount of waste (mine tailings) during and after operations. This problem became on top of housing-related challenges experienced by such communities, which stemmed from the high cost of transporting construction materials, the harsh climate, and the short construction season. In addition, the utilization of the traditional construction methods is often time-consuming (exceeding the time available) and relies on the supply of various materials that must be transported long distances (high cost), often via the south-north corridor. A possible solution is to apply an optimized construction method (3D concrete printing technology), which will alleviate the preceding challenges. However, this technology needs a high cement content, which is not only unsustainable due to the detrimental impacts of cement production on the environment but also compromises the structural integrity of the 3D printed element due to issues such as volume instability. Replacing part of the cement in the 3D printed concrete with regionally sourced materials such as the waste mine tailings would not only attenuate the burden of waste disposal in the mining industry but would help progress towards safer and more resilient houses in Northern Canada. The proposed research program will (i) develop innovative concretes incorporating waste mine tailings and investigate their early-age and long-term properties under simulated field conditions, (ii) optimize the developed concretes and assess their readiness for field applications, and (iii) satisfy the requirements of 3D printed concrete in terms of the pumpability, extrusion, and buildability. The originality of this work lies in capturing the role of mine tailings in modifying cementitious systems and testing their stability under harsh service conditions, which typically aggravate the decay of transportation infrastructure in Canada, thereby enhancing the reliability of assessment to optimally select materials for field applications. The outcome of this research program is expected to provide a robust, sustainable, and affordable solution for the irritating housing problems for the Northern communities using an optimized construction method while reducing the load on landfills and GHG emissions accompanied by the operation of the Ring of Fire project and contribute to preserving natural resources. The program will effectively contribute to the wider acceptance and use of innovative concretes with less cement and with industrial waste in various infrastructural applications.