The role of FRP composites in a sustainable world

Abstract

Use of fiber reinforced polymer (FRP) composites for construction of new structures and rehabilitation of existing structures has increased significantly over past decades. FRP composites are lightweight, noncorrosive, exhibit high specific strength, and specific stiffness, are easily constructed, and can be tailored to satisfy performance requirements. For structural applications, FRP composites are typically fabricated using a polymer matrix, such as epoxy, vinylester, or polyester, and reinforced with various grades of carbon, glass, and/or aramid fibers. Due to its advantageous characteristics, FRP composites have been included in new construction and rehabilitation of structures through its use as reinforcement in concrete, bridge decks, modular structures, formwork, and external reinforcement for strengthening and seismic upgrade. While the mechanical advantages of using FRP composites are widely reported in literature, questions remain in regards to the feasibility of FRP composites within the framework of a sustainable environment. The fabrication of constituent materials for FRP composites, namely matrix and fiber, are areas of concern especially when considering that the primary resources from which polymers (excluding biopolymers) are produced are crude oil, natural gas, chlorine, and nitrogen (Gerdeen et al. 2006). The most commonly used fiber reinforcements in structural applications, glass and carbon fibers, require high temperatures (1,400 C for glass; 1,200–2,400 C for carbon) during production and in some cases require petroleum by-products as precursors. When considering only energy and material resources it appears, on the surface, the argument for FRP composites in a sustainable, built environment is questionable. However, such a conclusion needs to be evaluated in terms of potential advantages present in use of FRP composites related to considerations such as: