FRP reinforcement includes GFRP and BFRP rebar, mesh, and rock bolting systems. These products provide non-metallic reinforcement and ground-support components for applications where corrosion of conventional metal reinforcement is a consideration. Design of concrete elements with FRP bars references ACI 440.1R. Ground-support applications require evaluation of ground conditions and project-specific installation requirements.
What is FRP Reinforcement
FRP reinforcement uses continuous glass or basalt fibers embedded in a thermosetting resin matrix. Many linear FRP reinforcement products, such as rebar and rock bolts, are manufactured by pultrusion. Product forms include rebar, mesh, and rock bolts. FRP reinforcing bars are generally linear elastic and do not exhibit steel-like yielding, so their design requires different considerations from steel reinforcement. Surface deformations and coatings are used to modify the bond characteristics of FRP bars with concrete. Specific mechanical properties depend on fiber type, resin system, product form, and geometry.
Typical Environments
FRP reinforcement is used in two broad areas. In concrete construction, it is commonly considered for marine structures, bridge decks exposed to de-icing salts, chemical containment structures, and electrical substation foundations. In ground support, FRP products such as rock bolts and anchors are used in tunnels, slope stabilization, and other ground-support applications. Selection depends on the project environment, structural or ground conditions, installation method, and product configuration.
Frequently Asked Questions
Can GFRP rebar be bent on site?
GFRP reinforcing bars are generally not field-bent like conventional steel rebar. Bent shapes are typically produced during manufacturing, while any field modification should follow the product-specific installation requirements.
Does GFRP rebar corrode?
GFRP rebar is non-metallic and does not undergo the electrochemical corrosion mechanism associated with steel reinforcement. Long-term performance can nevertheless depend on factors such as sustained loading, alkaline exposure, temperature, and the specific product configuration. These factors should be considered during design.
