Fiber-reinforced polymer waste in the construction industry: a review

Fiber-reinforced polymer composites, reaching a production of approximately 2.56 million tons in 2023 in Europe, display unique properties, yet they are disposed of at their end of service by conventional methods such as landfill and incineration. Here, we review the recycling of fiber-reinforced polymer wastes in the construction industry, with emphasis on fiber-reinforced polymer composites, recycling methods, and applications of carbon and glass fiber polymer composites in civil engineering. Recycling methods include mechanical, thermal, and chemical techniques. Applications comprise the use in fine fillers, coarse and fine aggregates, macro-fibers, alkali-activated materials, geopolymers, asphalt composites, and cement composites. We discuss workability, mechanical properties including compressive, flexural and tensile properties, durability, and surface modification. Future applications include three-dimensional concrete printing, self-sensing cement composites, self-heating and energy harvesting cement composites, and electromagnetic shielding. We propose a waste management hierarchy, considering the source of composites and their intended applications, to improve circularity.