Utilization of recycled carbon fiber reinforced polymer in cementitious composites: A critical review

The production and consequential waste of carbon fiber reinforced polymers (CFRP) is increasing owing to its utilization in various industries like automotive, aviation, electronics, military, sporting goods, etc. Likewise, the production of cementitious composites and related environmental concerns are also increasing. Therefore, research institutions and scientific groups are constantly looking for waste materials to be incorporated in cementitious composites to manage waste and promote sustainable development in the construction industry. Furthermore, conventional cementitious composites have low ductility, energy absorption capacity, and tensile strength. To counter these deficiencies, an alternative is to add steel rebars in cementitious composites, but it increases the risk of corrosion. As per the research studies, the incorporation of recycled CFRP (rCFRP) in cementitious composites can counter all the mentioned problems. Therefore, this study critically analyses the resourceful ways of recycling CFRP waste and the effect of rCFRP on the properties of cementitious composites. The properties discussed include workability, mechanical properties (i.e., compressive strength, flexural, strength, and tensile strength), impact resistance, electrical conductivity, and microstructure. Moreover, sustainability benefits and critical challenges of preparing rCFRP reinforced cementitious composites are also discussed comprehensively. The results reveal that the workability of cementitious composites decreases with increasing percentage incorporation of CFRP, thus, the suggested percentage addition is 0.25%. However, the addition of 0.25-1% rCFRP positively influences the mechanical properties and impact resistance of cementitious composites owing to the dense microstructure offered by rCFRP. In the case of electrical conductivity of cementitious compositions, the addition of 0.2-0.8% rCFRP is beneficial. It is also concluded that the addition of rCFRP promotes sustainable development, however, open issues and challenges related to the recycling of CFRP and properties of rCFRP modified cementitious composites (particularly durability properties) need further investigation.