Why Reading a Test Report Matters
With GFRP rebar, quality varies significantly between manufacturers. A test report is your only protection.
The 7 Parameters That Matter Most
1. Tensile Strength
What to look for: IS 18256:2023 minimums. Good quality: 1000–1200 MPa. Red flag: below 900 MPa.
2. Modulus of Elasticity
What to look for: 40–50 GPa. Below 35 GPa suggests poor fibre content.
3. Alkaline Conditioning Retention
What to look for: Minimum 85% tensile strength retention. Red flag: below 80%.
4. Transverse Shear Strength
What to look for: Minimum 150 MPa.
5. Bond Strength
What to look for: Minimum 10 MPa. Red flag: smooth bar with no surface deformation.
6. Fibre Volume Fraction
What to look for: 55–70% fibre by volume. Red flag: below 50%.
7. Water Absorption
What to look for: Less than 0.25% weight gain after 24 hours.
Checklist: What to Ask Your Supplier
- Is the test report from a NABL-accredited laboratory?
- Is tensile strength above 900 MPa?
- Is alkaline retention above 85%?
- When was the test conducted?
RN Elements provides complete NABL-accredited test documentation with every order.