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195290 https://hdl.handle.net/2286/R.2.N.195290 http://rightsstatements.org/vocab/InC/1.0/ All Rights Reserved 2024 248 pages Doctoral Dissertation Academic theses Text eng Simon, Aswathy Neithalath, Narayanan Mobasher, Barzin Hoover, Christian Hernández-Cortés, Danae Rajan, Subramaniam Arizona State University Partial requirement for: Ph.D., Arizona State University, 2024 Field of study: Civil, Environmental and Sustainable Engineering The non-conventional waste particulates and fibers to develop sustainable concrete mixtures, emphasizing their mechanical and durability properties, life cycle impacts, and cost-benefit analysis, is explored. The introductory sections provide a comprehensive background and literature review on sustainable construction materials. The characterization of post-consumer carpet fibers and optimization of concrete mixtures with high fiber volumes (2.5% and 5%) are explored in depth. Using Fourier transform infrared (FTIR) spectroscopy, different fiber types in carpet bales are identified, and their tensile strengths are assessed. A cradle-to-gate life cycle analysis demonstrates that incorporating carpet fibers and fly ash reduces CO2 emissions by ~12.5% with a compressive strength > 40 MPa compared to conventional concrete and lessens other environmental impacts, making carpet fiber-reinforced concrete a sustainable alternative. To evaluate the potential of applications in real-world scenarios and address the widespread disposal problem of carpets, the study evaluates the durability of post-consumer carpet fibers in concrete under various alkaline conditions. The findings show that moderate-strength concretes (~40 MPa) with 2.5% carpet fibers attain performance comparable to control mixtures, suggesting a sustainable use for these fibers in construction. Additionally, the research examines cement-free binders using mine tailings (MT) and slag. FTIR and thermogravimetric analysis (TGA) were used to assess the reaction products formed. It is also observed that mine tailing-slag (MT-S) blends significantly reduce heavy metal leaching, demonstrating their potential as a environmentally viable strategy to upscale MT wastes. Further investigation into the mechanical (compressive and flexural strengths), and the durability (Rapid chloride permeability (RCP), non-steady state migration (NSSM), length andstrength variations in alkaline environment) properties of MT carpet fiber blends, provides a comparison to the cement-based carpet fiber blends. A cradle-to-gate life cycle assessment compares the sustainability aspects of the conventional mortars, cement-based carpet fiber mixtures, alkali-activated MT-S blends, and MT carpet fiber blends. This analysis is complemented by a cost-benefit evaluation. Overall, this thesis thoroughly analyses innovative and sustainable concrete alternatives, highlighting the environmental and economic benefits of incorporating MT and carpet fibers into construction materials. The findings suggest promising pathways for reducing landfill waste and greenhouse gas emissions while maintaining or enhancing concrete performance, paving the way for more sustainable building materials in the industry. Civil Engineering Sustainability Capet fiber concrete Durability of concrete life cycle assessment Mine tailing binder Performance cost and sustainability index Sustainable concrete Non-Conventional Binder Components and Fiber For Sustainable Concretes