Technical specification.
The complete engineering data for Composite Group GFRP rebar — mechanical, composition, durability and sustainability — with the certified diameter range. Values are substantiated by ETA 23/0523; mill test certificates and the data sheet ship on request.
The material in numbers.
The values below are independently verified. Mill test certificates, the European Technical Assessment and the EPD are available on request.
- Tensile strength σₜ
- 940 – 1,200 MPa (B500B steel: 500 MPa) — lower at larger diameters
- Modulus of elasticity E
- ~ 52 GPa (B500B steel: 205 GPa)
- Strain at failure
- εₜ₀ₖ ≈ 0.02 (B500B steel: > 0.05) — linear-elastic to failure, no yielding
- Compressive strength
- 280 – 450 MPa, varies with diameter
- Transverse shear τ
- 145 – 200 MPa, decreases with diameter
- Density
- ~ 2.0 g / cm³ — 1/4 the density of steel
- Bond β
- ≈ 1.0 — comparable to ribbed steel
- Process
- Nidletrusion — 2nd-generation continuous winding
- Reinforcement
- Continuous E-glass fibre, 80 %+ by mass
- Matrix
- Nano-epoxy resin
- Surface
- Sand-coated + continuous helical wrap
- Properties
- Non-magnetic · non-conductive · radio-transparent
- Thermal exp. α
- 4.8 – 5.4 × 10⁻⁶ /°C (axial) · ~ 17 × 10⁻⁶ /°C (transverse)
- Corrosion
- Free — chlorides, salts, moisture, alkalis, acids
- Service life
- 80+ years in alkaline concrete (pH 9 – 13)
- Working temp.
- up to ≈ 65 °C (max. service temp · ETA) · T_g ≈ 90 °C
- UV exposure
- Protect during transport and storage; site-shaded use after pour
- Fatigue
- Lower than steel — not ideal under cyclic loads; design measures required
- Fire
- Limited combustibility — driven by resin Tg, for buried / encased use
- CO₂ in production
- Up to 70 % lower than equivalent steel rebar (EuCIA verified)
- Truck ratio
- 1 GFRP truck ≈ 7–8 steel trucks (1/4 density, 2.4× strength)
- Recyclability
- Cement-bound aggregate route + mechanical grinding
- EPD
- EN 15804 +A2 compliant
- Sourcing
- European supply chain · single-site manufacturing
- Constitutive law
- Linear-elastic to failure — no yielding, different from steel
- Compensation
- Confinement, higher strength reserve, or hybrid with steel rebar in compression
- Standards
- ACI 440.11-22 · CSA S806/S807 · fib Model Code 2020 · ISO 10406-1
- EU certification
- ETA 23/0523 (EAD 260023-00-0301) — first ETA for GFRP rebar in Europe
- product.spec.g4.r4.k
- product.spec.g4.r4.v
Certified
Ø 6 to 16 mm.
Composite Group GFRP rebar is ETA-certified in Ø 6, 8, 12 and 16 mm. Smaller diameters ship in continuous coils for slab and deck work; larger diameters as straight bars cut to length. Characteristic tensile strength decreases with diameter, as recorded in ETA 23/0523.
| Diameter | Cross-section | Mass / m | Tensile (char.) |
|---|---|---|---|
| Ø 6 | 28.3 mm² | 0.06 kg | > 1,100 MPa |
| Ø 8 | 50.3 mm² | 0.10 kg | > 1,100 MPa |
| Ø 12 | 113 mm² | 0.23 kg | > 1,050 MPa |
| Ø 16 | 201 mm² | 0.40 kg | > 880 MPa |
Characteristic values per ETA 23/0523. Stirrups, links and custom shapes are factory pre-formed.
Installation notes.
GFRP installs with the kit a site team already owns — with two differences from steel that matter on the drawing.
Cut on site with a standard diamond or carbide blade. No welding and no heat.
GFRP cannot be bent on site. Stirrups, links and custom shapes are factory pre-formed to the bending schedule — order them to drawing.
Concrete cover follows EN 1992 for the exposure class. Corrosion is no longer the driver, but the cover still does its structural and bond job.
Four times lighter than steel — manual handling, fewer lifts. Protect from prolonged UV in storage; site-shaded after the pour.
Data sheet
and certificates.
The full data sheet, ETA 23/0523, the EPD (EN 15804 +A2) and per-diameter mill test certificates are available on request.