The Endurobar range.
Straight bars, custom bends, mesh and fabricated composites — all corrosion-free, all engineered to the same IS 18256 standard.
GFRP Rebar
Straight, sand-coated bars in IS 18256 sizes G4 to G32 — coils or cut lengths up to 12 mm, 8 m / 12 m bundles above. The corrosion-free alternative to steel rebar.
Bent Bars & Stirrups
L-bends, U-bends, links and stirrups pre-formed to your bar-bending schedule — no site fabrication needed.
GFRP Mesh
Pre-tied reinforcement mesh for slabs, screeds, pavements and industrial floors. Lightweight and fast to place.
Gratings & Manhole Covers
Load-rated FRP gratings and covers that never rust, never get stolen for scrap, and never need repainting.
Cable Trays
Non-conductive, corrosion-proof cable management for industrial, chemical and coastal installations.
Precast Cages
Prefabricated GFRP cages and assemblies built to your drawings for precast and modular construction.
Sizes & Guaranteed Strength
Standard sizes G4 to G32
Each size carries a minimum guaranteed tensile force under IS 18256. Bar size and spacing are designed from your loads — never swapped one-for-one with steel.
| Size | Ø mm | Nominal area mm² | Min. tensile force kN | Min. bend radius mm |
|---|---|---|---|---|
| G4 | 4 | 12.6 | 11 | 12 |
| G6 | 6 | 28.3 | 23 | 18 |
| G8 | 8 | 50.3 | 40 | 24 |
| G10 | 10 | 78.5 | 60 | 30 |
| G12 | 12 | 113.1 | 80 | 36 |
| G16 | 16 | 201.1 | 130 | 48 |
| G20 | 20 | 314.2 | 190 | 60 |
| G25 | 25 | 490.9 | 270 | 100 |
| G32 | 32 | 804.2 | 420 | — |
Source: IS 18256:2023, Table 1. Full material limits, handling rules and standards are on the Technical Data page.
Mechanical Properties
Endurobar GFRP vs. metal rebar
| Property | Metal Rebar | Endurobar GFRP |
|---|---|---|
| Tensile strength (MPa) | 500 – 600 | Guaranteed per size — IS 18256 Table 1 |
| Shear strength (MPa) | 120 | ≥ 130 |
| Bond strength to concrete (MPa) | 14 | ≥ 7.6 |
| Modulus of elasticity (GPa) | 160 – 200 | ≥ 45 |
| Ultimate strain / elongation (%) | 25 | ≥ 1.1 |
| Glass transition temp. Tg (°C) | — | ≥ 100 |
| Alkali resistance (90 d, 60 °C) | Corrodes in aggressive env. | ≥ 80% strength retained |
| Density (t/m³) | 7.8 | 1.9 |
| Corrosion resistance | Rusts in aggressive env. | Inert in alkaline concrete |
| Electrical conductivity | Conductive | Dielectric |
Engineered Attributes
Eighteen reasons engineers switch
Frequently Asked
Answers for spec engineers
GFRP is designed for, not swapped one-for-one — its stiffness and failure behaviour differ from steel. Our engineers work from your design loads to specify bar size and spacing, and diameters are never substituted on site.
Absolutely. Endurobar is BIS-licensed and manufactured to IS 18256:2023 and IS 18255:2023, with ASTM D7957 conformance and NHAI approval for infrastructure work.
Bends are formed during manufacture — GFRP cannot be bent on site like steel. Send us your bar-bending schedule and we deliver ready-formed bent bars, stirrups and links.
IS 18256 sizes G4 to G32. Bars up to 12 mm come in coils or straight lengths; larger bars ship in 8 m or 12 m bundles. Custom lengths and bent shapes to order.
There is no steel to corrode, so the reinforcement is not attacked by moisture, chlorides or alkalis. IS 18256 requires no creep rupture at a sustained 35% of ultimate load and ≥ 80% alkali-strength retention — the basis for long-term durability.