Advances in Sustainable Composite Materials for Civil Infrastructure Applications

Abstract

Aging, corrosion-prone steel-reinforced concrete and the carbon footprint of conventional construction materials have pushed civil infrastructure toward an expanding family of composite alternatives: fiber-reinforced polymer (FRP) reinforcement, natural-fiber and bio-based composites, geopolymer binders, and the recycling and circularity technologies that increasingly surround all of them. This article synthesizes that literature across five themes: the material and mechanical foundations of glass, carbon, and basalt FRP composites; the multi-year durability evidence for FRP reinforcement in alkaline, marine, and acid concrete environments; structural applications spanning internal reinforcement, external strengthening, and integrated bridge deck systems; natural-fiber, bio-based, and geopolymer alternatives alongside self-healing composites that extend service life by design; and the life-cycle assessment and end-of-life recycling literature, including the quantified environmental and cost tradeoffs among mechanical, thermal, and chemical CFRP recovery routes and the emerging practice of repurposing decommissioned wind turbine blade composite into new civil structures. Read together, the evidence supports FRP and related composite technologies as an increasingly well-evidenced, appropriately bounded option for specific infrastructure problems -- corrosion-prone reinforcement, rapid deck replacement, retrofit strengthening, and circular reuse of composite waste -- while leaving geopolymer-FRP durability compatibility, multi-stressor exposure testing, natural-fiber's structural ceiling, and recycling economics as an open research and standardization agenda.