Improving the Process for Cold Weather Concreting: Novel Concrete Mixtures and Innovative Curing Methods

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In cold climate countries, freezing temperatures impede construction activities or put them on hold until warmer seasons, as concreting activities under such conditions are quite challenging. This leads to considerable socioeconomic losses. Ready-mix concrete suppliers have to frequently conduct exhaustive trial batches with heated constituents and multiple admixture systems to produce winter concrete, resulting in technical issues such as high internal temperatures of concrete or loss of target fresh, mechanical and durability properties of this concrete. Moreover, contractors have to implement thorough heating and hoarding practices at job sites to heat-cure concrete elements and their surrounding areas in winter, which entail additional materials, energy and labor resources with associated delays in productivity and extra costs. This Discovery Grant proposal aims at utilizing nanoparticles (size scale of 1-100 billionth of a meter) and phase change materials (thermal storage/release reservoirs) to mitigate challenges of cold weather concreting. This research program will: i) develop innovative concrete mixtures for cold weather that incorporate nanoparticles with antifreeze admixtures and test their fresh, hardened and durability properties, ii) investigate the functionality of phase change materials as a novel protection method for mitigating the effects of freezing temperatures on these concretes, iii) build intelligence-based models for predicting their behavior under field conditions, and iv) conduct verification studies on large-scale elements to pave the way for field applications. This novel research program stems from a paradigm shift, which employs nanotechnology to engineer the next generation of concrete. The originality of this work lies in elucidating the interactive roles of nanomaterials, antifreeze admixtures and phase change materials in modifying cementitious systems produced under low/freezing temperatures and rigorously testing their stability under harsh conditions of transportation and wastewater infrastructure, with predictive modeling. This research will advance the current knowledge on cold-weather concreting, which is a critical issue for Canada and other cold regions. It will mobilize novel projects on the use of innovative materials and protection methods for concreting at a range of low and freezing temperatures, which is envisioned to enable longer construction and maintenance of concrete elements/structures in late fall, winter and early spring with better productivity rates and offer developmental solutions to northern parts of Canada. Throughout the course of this research program, practical outcomes (e.g. innovative concrete mixture designs for cold weather and associated protection requirements) can be incorporated in construction and maintenance specifications for concrete in Canadian jurisdictions and standards for concrete, with a measurable impact on the construction industry in Canada and elsewhere.