Recycled Glass and PET Waste as Aggregates Replacement in Eco-Innovative Concrete for Alveolar Concrete Blocks

This paper presents the results of a research project focused on prevention of environmental degradation by developing ecological concrete by simultaneously integrating two types of recycled wastes, namely glass waste (GW) and PET (Polyethylene Terephthalate) waste, as high percent of natural aggregate substitution. After initial analysis, both in fresh state and hardened state as well, of the eco-concrete resulted by considering several substitution possibilities, a possible direct domain of applicability is considered in terms of Lego type alveolar concrete blocks. The direct beneficiary of the research outcomes is a private company, SC NEW NCR RECYCLING SRL, which has both, the collection and recovery of waste on one hand, and concrete products manufacturing, on the other hand, as main activity domains. The company initially owned significant waste disposal facilities with relatively limited possibilities for final disposal. Limits are imposed by end-of-life recyclers due to waste quality requirements: one single type of waste, no blend of color, high purity, etc. Hence, the project main goal was to innovatively capitalize these existing, available waste stocks of Glass and PET, for which the current recycling possibilities were limited, by integrating them as raw materials in concrete and further on in concrete construction products. Therefore, the considered wastes, glass, and PET, were correspondently processed to transform them into viable raw materials for concrete, as natural aggregate substitution. Several concrete mixes were designed and comparatively analyzed, followed by their effective use for precast concrete products for the construction industry, in full agreement to Circular Economy principles.