Recycled Fibers in Reinforced Concrete: a systematic literature review

Concrete is one of the leading composite materials for construction, therefore the identification of strategies aimed at reducing its environmental impact is crucial for greening the building industry and achieving the Sustainable Development Goals set by the United Nations. One way to reduce this impact involves the opportunity to recycle waste materials as fiber in concrete reinforcement, thus following the circular economy principles. The feasibility of using different waste materials in Recycled Fiber Reinforced Concrete (RFRC) is attracting practitioners’ attention. Through a systematic literature review, the paper analyzes the academic literature on concrete reinforcement using recycled fibers. The main goal is to provide an exhaustive analysis of the phenomenon with rigorous and reproducible research criteria. Eventually, 194 articles were analyzed. RFRC is a research topic, which is rapidly growing over the last years and scholars’ attention is focused both on engineering aspects, through experimental studies testing the composite mechanical properties, and environmental sustainability considerations. From the analysis, emerged that even though the relevance of the construction industry and, as a consequence, of concrete in the global transition toward sustainability it is widely recognized, there is a gap in investing the potential of RFCR in addressing the triple bottom line of it. Finally, it emerged a great research potential in exploring how recycled fibers may be part of a construction industry-oriented and inspired to circular economy principles.