New eco-sustainable construction materials derived from industrial wastes

"Managing waste is equivalent to addressing the problems of our time." This phrase resonated throughout the entire PhD period. Waste management is necessary for every industrial activity nowadays, but it begins with awareness of the community and everyone. Over time, this awareness helps us recognise the value of what we have, rather than seeking it elsewhere. The research project emerged from the need of local industries to manage their waste, aiming to find potentially feasible applications that could give new life to materials previously considered burdensome both economically and socially. Indeed, the waste treated in this thesis has a high impact, posing a constant challenge for local companies, with whom a close collaboration has been established to meet their needs as effectively as possible. Notably, construction and demolition waste (CDW) from the earthquake that devastated Central Italy in 2016 plays a central role. The study of the CDW also aimed at the study of other types of CDW coming from different geological and construction contexts, showing how an accurate characterisation of this material is crucial to understanding its recycling potential and limits. Other waste investigated beyond CDW included organic resin-based materials, such as wind blade scraps from the management of wind turbine blades that have reached the end of their life cycle. Their in-depth characterisation was conducted to explore the best applications in the construction context, investigating both Portland cement (PC) and geopolymer. The latter was scrutinised for its potential to accommodate a greater volume of waste materials, to exhibit reduced CO2 emissions compared to traditional ordinary Portland cement (OPC), and for its remarkably high mechanical properties and durability. Using geopolymer has allowed the production of binders with a very high waste content, with both fly ash and volcanic ash used, demonstrating the enormous potential this type of binder can provide in designing eco-sustainable building materials. The findings shed light on the physical and mechanical properties of cementitious materials, contingent upon the constituents and their respective quantities. Specifically, construction waste has proven to be exploitable for the formation of interlocking brick, while resin-based materials have offered a broad range of applications given their remarkably high mechanical performance. Throughout, the research keeps in mind economic feasibility, waste content optimisation, and suitability for intended applications, with a steadfast commitment to sustainability encompassing social, environmental, and economic considerations.