Reinforcing steel (rebar) carries the tensile loads in concrete structures, so producers, buyers and testing laboratories check it carefully against product standards such as ASTM A615/A615M or BS 4449. Tests fall into three groups: geometry, mass and mechanical properties.
On this page
1. Rib geometry
The ribs (deformations) on a bar create the mechanical bond with concrete. Product standards control their geometry, which can include:
- Rib height and rib spacing.
- Rib inclination and the gap between rib ends.
- Relative rib area (fR) — a single parameter describing bond capacity, calculated from rib dimensions; test methods are given in ISO 15630-1.
Measuring these by hand with calipers and gauges is slow and operator-dependent. Automated systems such as Psaron’s RIB3D scan the bar and measure a large set of geometric parameters automatically, improving speed and repeatability.
2. Mass per metre
Bars are weighed and measured to calculate mass per unit length, which is compared with the nominal value and tolerance for the bar size. It confirms the effective cross-section of the bar.
3. Mechanical properties
- Yield strength — the stress at which the bar begins to deform permanently.
- Tensile strength — the maximum stress before failure.
- Elongation — ductility, often with limits on the ratio of tensile to yield strength.
- Bend or rebend tests — the bar is bent around a mandrel to check for cracking.
These require a universal testing machine with suitable grips and capacity for the largest bar diameter, plus bend testing fixtures.
Who needs rebar testing equipment?
- Rebar mills, for production control and certification.
- Construction laboratories and consultants, for acceptance testing.
- Contractors and government departments, for verification on major projects.
We supply metal testing equipment including Psaron’s RIB3D system in Pakistan. Contact us to discuss your rebar testing requirements.