| Property | GFRP rebar | Steel rebar |
|---|---|---|
| Corrosion | Does not rust or corrode from chlorides | Corrodes; the main cause of concrete deterioration in marine and de-icing salt settings |
| Density | about 2.0–2.2 g/cm³ (about a quarter of steel) | 7.85 g/cm³ |
| Tensile strength | High in tension; depends on bar diameter and manufacturer | Yields at a defined strength |
| Modulus of elasticity | about 40–60 GPa | about 200 GPa |
| Behaviour at failure | Linear elastic until rupture; no yielding | Ductile yielding |
| Electrical and magnetic | Non-conductive, non-magnetic | Conductive, magnetic |
| Bending on site | Not possible; bends are made in the factory | Easy |
| Cost per kg | Higher | Lower |
How the design differs
- Serviceability governs: with a lower modulus, crack width and deflection limits decide how much GFRP is needed.
- No ductility: design for failure that is concrete crushing rather than bar rupture, as guidance documents recommend.
- Different design codes: use an FRP-reinforcement guide or standard for the project (for example ACI 440.1R, CSA S806 or the local equivalent) and a product specification such as ASTM D7957.
- Detailing: bend radii and hooks are made to order; lap lengths and cover differ from steel.
Where it makes sense
- bridge decks, sea walls, marine and coastal structures;
- parking structures and slabs exposed to de-icing salts;
- tunnels (temporary or soft-eye zones), water treatment and chemical plants;
- MRI rooms, substations and rail where non-magnetic, non-conductive reinforcement is needed.
Cost: compare per function
GFRP costs more per kilogram, but it is about a quarter of the weight and does not need extra cover or later repair in corrosive settings. Compare on the cost of the whole member and its maintenance, not on price per kg: see life-cycle cost.
Residential use
Check that your local building authority accepts GFRP reinforcement and the design method. For ordinary dry house foundations steel is cheaper and fully covered by codes; GFRP is worth considering for basements, pool decks and coastal homes. Limits and handling: GFRP rebar limitations. How it is made: GFRP rebar manufacturing.
Frequently asked questions
How do I choose a rebar supplier?
Ask for the product specification and test reports (tensile, bond, glass content, cure), batch traceability, and samples; compare them with the standard named in your project.
Send us your requirement
Guangdong Haikuo Composite Materials Co., Ltd. (Huizhou, Guangdong) designs pultrusion moulds in-house and produces custom FRP profiles. Send a drawing, a sample or just the application and the environment, and we will tell you what is feasible.
Email: helena@frphk.cn | Phone: +86 189 5198 8522