Fiber reinforced polymer (FRP) composites are thin laminates that are externally bonded to structural members using epoxy adhesive. The FRP significantly increases the members' load carrying capacity.

These structural strengthening systems are made of high strength fibers (such as glass, kevlar, and carbon) embedded in a resin matrix. The resin protects the fibers, maintains their alignment, and distributes the loads evenly among them.

FRP's, which have been extensively used in industries such as aerospace, automotive, and sport equipment, are now becoming a mainstream technology for the structural upgrade of concrete structures. In addition to their high-strength and lightweight properties, important characteristics of FRPs for structural repair and strengthening applications are their non-corrosive properties, speed and ease of installation, lower cost, and aesthetics. FRP fabrics may be adhered to beams and slabs to increase their shear and flexural capacity, and can be wrapped around columns to increase their load carrying capacity and ductility for seismic events.

FRP systems may also consist of pre-cured bars and plates that are bonded to structural elements using epoxy adhesive. Pre-cured FRP elements are more suited for flexural upgrade of columns, beams, and slabs. As with any other externally bonded system, the bond between the FRP system and the existing concrete is critical to achieve a composite behavior with the existing member. Accordingly, proper surface preparation is a key process for ensuring a successful FRP strengthening application.

FRP Advantages

• High tensile strength
• Lightweight and thin
• Corrosion resistant
• Lower construction costs
• Can be applied to non-flat shapes