Fiber-reinforced polymer (FRP) composites have been used for structural strengthening in the U.S. since the 1990’s. The use of FRP in lieu of steel for strengthening and repair of concrete is gaining acceptance among engineers and owners due to a number of factors, including strength, speed and cost.
FRP composite systems are made up of high strength continuous fibers, such as carbon or glass, embedded in a polymer resin matrix. The fibers provide the main reinforcing strength while the polymer matrix (usually epoxy or MMA) acts as a binder, protects the fibers, and distributes the load.
FRP composites have been successfully used to strengthen buildings, bridges, tanks, and pipes. The FRP raw material costs are sometimes higher but are frequently offset by reduced labor, equipment, and downtime costs, often making FRP more cost-effective than strengthening with steel.