🔩 Reinforcing Steel Testing (Tensile, Bending)
In short
Test methods for reinforcing bars, rods and wire for concrete: tensile test, bend test, rebend test, as well as the fatigue test, measurement of rib geometry and of the deviation from nominal mass per metre. The test is performed according to PN-EN ISO 15630-1:2019-04; Standard methods: tensile, bend, rebend, axial fatigue, chemical analysis, geometrical characteristics, fR/fP, mass per metre (clauses 5–12). The procedure comprises 6 steps; it is used for: Testing of reinforcing bars, rods and wire for concrete by the standard methods of the standard (clauses 5–12), Checking the properties required by the product standard — the test standard gives the method, while the requirements and acceptance criteria are taken from the product standard, Specialized tests (clause 13) — only where the product standard specifies them: tensile tests at elevated and low temperature, cyclic inelastic load test.
At a glance
- Standard: PN-EN ISO 15630-1:2019-04
- Category: Construction
- Procedure steps: 6
- Standard methods: tensile, bend, rebend, axial fatigue, chemical analysis, geometrical characteristics, fR/fP, mass per metre (clauses 5–12)
- Testing machine: according to ISO 7500-1, at least class 1
- Extensometer: class 1 according to ISO 9513 for Rp0.2; class 2 permitted for Agt, gauge length at least 100 mm
Overview
STATUS (as of 06.11.2026). PN-EN ISO 15630-1:2019-04 “Stal do zbrojenia i sprężania betonu — Metody badań — Część 1: Pręty, walcówka i drut do zbrojenia betonu” (Steel for the reinforcement and prestressing of concrete — Test methods — Part 1: Reinforcing bars, rods and wire) — Polish version, published 06.07.2020, implements EN ISO 15630-1:2019 and ISO 15630-1:2019 [IDT]; it replaced PN-EN ISO 15630-1:2011 (Polish and English versions). The card has no withdrawal note — the standard is current. ISO 15630-1:2019 (third edition, 07.02.2019) replaced the 2010 edition; among other things, clause 4 (general provisions concerning test pieces), 5.3 (tensile test procedure) and 6.3 (bend test procedure) were changed and clause 13 with specialized tests was added.
SCOPE AND STRUCTURE OF THE STANDARD (introduction, table of contents). The ISO 15630 series aims to collect in one place the test methods for steels for the reinforcement and prestressing of concrete; part 1 covers reinforcing bars, rods and wire. The standard methods are: tensile test at room temperature (clause 5), bend test (clause 6), rebend test (clause 7), axial force fatigue test (clause 8), chemical analysis (clause 9), measurement of geometrical characteristics (clause 10), relative rib or indentation area fR, fP (clause 11) and deviation from nominal mass per metre (clause 12). Clause 13 collects specialized tests — tensile tests at elevated and at low temperature and the cyclic inelastic load test — used only where the product standard specifies them. For the testing of metals in general the standard refers to ISO standards (tensile testing — ISO 6892-1) and gives complementary provisions.
TENSILE TEST (clause 5). Testing machine verified and calibrated according to ISO 7500-1, at least class 1. Extensometer for determining Rp0.2 — class 1 according to ISO 9513; for the percentage total elongation at maximum force Agt a class 2 extensometer is sufficient, and the extensometer gauge length for Agt is at least 100 mm and is given in the test report. In the 2010 edition (5.3, changed in the 2019 edition — we do not know the new wording), the test was carried out according to ISO 6892-1; the strength was calculated on the nominal cross-sectional area unless the product standard specified otherwise; the elongation after fracture A was measured on a gauge length of 5 nominal diameters unless the product standard specified otherwise; Agt determined manually after fracture was calculated as Ag + Rm/2 000, with Ag measured on the longer broken part over a length of 100 mm at a distance of at least 50 mm or 2d from the fracture.
BEND TEST (clause 6). The test piece is bent over a mandrel — in a device with mandrel, support and carrier, or in a device with supports and a mandrel (e.g. according to ISO 7438). The angle of bend and the mandrel diameter D are specified by the relevant product standard. The result is interpreted according to the requirements of the product standard; if these are not specified, the absence of cracks visible to a person with normal or corrected vision means that the test piece has withstood the test. A superficial ductile tear at the base of the ribs or indentations is not a failure — when its depth is not greater than its width. In the 2010 edition the test was carried out at a temperature between 10 °C and 35 °C unless otherwise agreed by the parties (6.3 was changed in the 2019 edition).
REBEND TEST (clause 7, according to the 2010 edition). The test has three steps: bending over a mandrel (angle and diameter according to the product standard, inspection for cracks and fissures), artificial ageing (temperature and time according to the product standard, and if not given — according to the general provisions of the standard) and bending back by a specified angle after free cooling in still air to a temperature between 10 °C and 35 °C. The result is interpreted as in the bend test.
MASS PER METRE (clause 12, according to the 2010 edition). The test piece has square-cut ends; length and mass are measured to an accuracy of at least ± 0.5 %. The deviation is determined from the difference between the actual mass per metre (from the mass and length of the test piece) and the nominal mass per metre given in the product standard.
WHAT WE DO NOT GIVE HERE. Requirements for steel grades (yield strength, ratio Rm/Re, Agt, mandrel diameter, angle of bend, number of test pieces per batch) — these are set by the product standard, not by the test method standard. Loading rates in the tensile test — they are given by ISO 6892-1 (separate Knowledge Base entry). The new wording of clause 4 and of 5.3 and 6.3 of the 2019 edition — the available preview of the standard ends with the introduction, and the description of these clauses comes from the 2010 edition; where the 2019 edition changed them, this is indicated in the text.
Method principle
Tensile test: a test piece of bar, rod or wire is pulled according to ISO 6892-1 with the complementary provisions of the standard (machine at least class 1, extensometer for Agt with a gauge length of at least 100 mm), and the yield strength (ReH or Rp0.2), tensile strength Rm, elongation after fracture A and percentage total elongation at maximum force Agt are determined.
Bend and rebend test: the test piece is bent over a mandrel of the diameter and to the angle given in the product standard (in the rebend test — bending, artificial ageing and bending back), and the result is interpreted according to the product standard, or, if it gives no requirements, by the absence of cracks visible to the naked eye.
Applications
- Testing of reinforcing bars, rods and wire for concrete by the standard methods of the standard (clauses 5–12)
- Checking the properties required by the product standard — the test standard gives the method, while the requirements and acceptance criteria are taken from the product standard
- Specialized tests (clause 13) — only where the product standard specifies them: tensile tests at elevated and low temperature, cyclic inelastic load test
Key parameters
| Parameter | Value |
|---|---|
| Standard methods | tensile, bend, rebend, axial fatigue, chemical analysis, geometrical characteristics, fR/fP, mass per metre (clauses 5–12) |
| Testing machine | according to ISO 7500-1, at least class 1 |
| Extensometer | class 1 according to ISO 9513 for Rp0.2; class 2 permitted for Agt, gauge length at least 100 mm |
| Determined in the tensile test | ReH or Rp0.2, Rm, A, Agt |
| Bend test | angle of bend and mandrel diameter according to the product standard; interpretation according to the product standard, and if no requirements — no cracks visible to the naked eye |
| Mass per metre (2010 edition) | length and mass of the test piece to an accuracy of at least ± 0.5 % |
Standard
- Standard number
- PN-EN ISO 15630-1:2019-04
- Title (PL)
- Stal do zbrojenia i sprężania betonu — Metody badań — Część 1: Pręty, walcówka i drut do zbrojenia betonu
- Title (EN)
- Steel for the reinforcement and prestressing of concrete — Test methods — Part 1: Reinforcing bars, rods and wire
Step-by-step procedure
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Test piece
The test piece is taken from the bar, rod or wire in the as-delivered condition unless the product standard specifies otherwise; a test piece taken from a coil is straightened before testing, and the method of straightening and any artificial ageing are given in the test report (clause 4 according to the 2010 edition — changed in the 2019 edition).
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Tensile test
Carry out according to ISO 6892-1 with the provisions of clause 5: machine at least class 1, class 1 extensometer for Rp0.2 (class 2 permitted for Agt, gauge length at least 100 mm). Determine ReH or Rp0.2, Rm, A and Agt; in the 2010 edition — on the nominal cross-sectional area, A on a length of 5d.
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Bend test
Bend the test piece over a mandrel in the device of Figure 2 of the standard or on supports with a mandrel; angle of bend and mandrel diameter according to the product standard (clause 6).
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Interpretation of the bend test
Interpret according to the product standard; if there are no requirements — absence of cracks visible to a person with normal or corrected vision. A superficial ductile tear at the base of the ribs with a depth not greater than its width is not a failure (6.4).
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Rebend test
Bend the test piece over a mandrel, subject it to artificial ageing according to the product standard, let it cool freely in still air to a temperature between 10 °C and 35 °C and bend it back by the angle given in the product standard; interpret as in the bend test (clause 7, according to the 2010 edition).
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Test report
According to the 2010 edition: reference to the standard, identification of the test piece with the nominal diameter, free length of the test piece, type of test and results, the product standard (where applicable) and other information on the test piece, equipment and procedure.
Required equipment and apparatus
| Equipment | Example | Indicative price |
|---|---|---|
| Testing machine | verified and calibrated according to ISO 7500-1, at least class 1 (5.2) | — |
| Extensometer | class 1 according to ISO 9513 for Rp0.2; class 2 permitted for Agt, gauge length of at least 100 mm given in the test report (5.2) | — |
| Bending device | mandrel, support and carrier (Figure 2 of the standard) or supports and mandrel, e.g. according to ISO 7438 (6.2) | — |
| Rebending device | the bending device or another rebending device (7.2) | — |
| Instruments for measuring length and mass | measurement of the length and mass of the test piece to an accuracy of at least ± 0.5 % for the deviation from mass per metre (12.2, 2010 edition) | — |
Health and safety (OHS)
- The standard gives no safety requirements — the rules for working at the testing machine and bending devices are set by the laboratory on the basis of a risk assessment
Frequently asked questions
Which standard describes this test?
The test is performed according to PN-EN ISO 15630-1:2019-04 — “Steel for the reinforcement and prestressing of concrete — Test methods — Part 1: Reinforcing bars, rods and wire”.
How does this method work?
Tensile test: a test piece of bar, rod or wire is pulled according to ISO 6892-1 with the complementary provisions of the standard (machine at least class 1, extensometer for Agt with a gauge length of at least 100 mm), and the yield strength (ReH or Rp0.2), tensile strength Rm, elongation after fracture A and percentage total elongation at maximum force Agt are determined.
What is the measuring range and accuracy?
Standard methods: tensile, bend, rebend, axial fatigue, chemical analysis, geometrical characteristics, fR/fP, mass per metre (clauses 5–12); Testing machine: according to ISO 7500-1, at least class 1; Extensometer: class 1 according to ISO 9513 for Rp0.2; class 2 permitted for Agt, gauge length at least 100 mm; Determined in the tensile test: ReH or Rp0.2, Rm, A, Agt.
How long does the test take?
The procedure comprises 6 steps. The standard does not give a duration for every stage — the laboratory's own procedure decides.
What equipment is required?
Testing machine, Extensometer, Bending device, Rebending device, Instruments for measuring length and mass.
Where is this test used?
Testing of reinforcing bars, rods and wire for concrete by the standard methods of the standard (clauses 5–12); Checking the properties required by the product standard — the test standard gives the method, while the requirements and acceptance criteria are taken from the product standard; Specialized tests (clause 13) — only where the product standard specifies them: tensile tests at elevated and low temperature, cyclic inelastic load test.
What safety precautions apply?
The standard gives no safety requirements — the rules for working at the testing machine and bending devices are set by the laboratory on the basis of a risk assessment.
Which laboratory can perform this test?
The test is performed by laboratories accredited to ISO/IEC 17025. On LabCoda you can find them by the standard number PN-EN ISO 15630-1.