SIST EN 13146-2:2012

SIST EN 13146-2:2012 is the SIST publication of EN 13146-2:2012, a CEN European Standard for railway applications. It specifies a laboratory test method for determining the torsional resistance of a complete rail fastening assembly by measuring the moment needed to rotate a rail through 1°, and the result is used in track stability calculations.

What does SIST EN 13146-2:2012 specify?

SIST EN 13146-2:2012 specifies how to test a rail fastening assembly in the laboratory to obtain a torsional resistance value. The test applies to a complete fastening assembly on a sleeper or half sleeper, and it is not applicable to embedded rails.

The document is organized into these main clauses:

• Scope
• Normative references
• Terms and definitions
• Principle
• Apparatus
• Test specimens
• Procedure
• Test report

This structure matters in practice because it tells a test laboratory what specimen to mount, what equipment to use, how to run the loading sequence, and what to report.

What are the key requirements of SIST EN 13146-2:2012?

Loading principle and result

Clause 4 states that a transverse load is applied to the foot of a rail fixed to one rail seat while the sleeper is restrained. The rail movement is recorded until the rail has rotated through at least 1.5°, and the moment needed to produce 1° of displacement is then read from the load-displacement graph. In practice, this gives a value that engineers can use in track stability calculations.

Rail, actuator and measuring equipment

Clause 5.1 requires a short length of the rail section for which the fastening assembly is designed, with the rail clean enough for repeatable contact. Clause 5.2 requires an actuator that can apply at least 25 kN at a controlled rate of (2 ± 1) kN/min, normal to the rail and parallel to the rail foot plane. This matters because the test depends on applying the load in a controlled and repeatable way.

Clause 5.3 requires displacement measurement to ± 0.1°; if linear measurement is used, the contact instruments must conform to EN ISO 9513:2002, Table 2, Class 2 and measure to ± 0.01 mm. Clause 5.4 requires force instruments conforming to EN ISO 7500-1:2004, class 1. Clause 5.5 requires periodic verification of calibration with traceable equipment using SI units.

Test specimens

Clause 6.1 requires the rail support to be a sleeper or half sleeper with cast-in fastening components or holes and rail seats, made as produced and without modification for the test. Clause 6.2 requires the fastening specimen to be the complete fastening assembly, including all components and the baseplate where relevant. In practice, the test is meant to reflect the fastening as it will be used, not a modified laboratory version.

Procedure and test arrangements

Clause 7.2 gives the loading sequence for fastenings in line, including loading from one side, then repeating from the opposite side after a minimum 3 min interval. Clause 7.3 says that if the fastenings are offset from the centre line, two tests are performed using the arrangements shown in Figure 2. The test also calls for continuous recording of moment and angular displacement, with the note that loading should stop as soon as contact is made that could damage the assembly.

Clause 7.4 points to Annex A for the graph used to extract the track-stability data. Clause 8 requires the report to identify the standard used, the laboratory, the test date, the fastening assembly and its components, the specimen origin, the rail section, the arrangement used, and the moment-versus-angle graphs for each loading direction.

What terms does SIST EN 13146-2:2012 define?

Clause 3 uses the terms and definitions from EN 13481-1:2012. Key terms in this document include:

• Fastening assembly - the complete set of components that secures the rail to the sleeper during the test.
• Sleeper - the rail support used with the fastening assembly in the test specimen.
• Rail seat - the support location on the sleeper where the rail is fixed.
• Rail support - a sleeper or half sleeper with rail seats and fastening provisions, used as the test base.
• Embedded rails - rails in an arrangement excluded from this test method.
• Track stability calculations - the downstream use of the torsional resistance value obtained from the test.

Who uses SIST EN 13146-2:2012?

SIST EN 13146-2:2012 is used by laboratories that test railway fastening systems, manufacturers of rail fastening components, and railway infrastructure organizations that need comparable data for design or assessment. It is also relevant to quality teams and buyers who need to verify that a complete fastening assembly has been tested by a defined method.

What changed in SIST EN 13146-2:2012 from the previous edition?

SIST EN 13146-2:2012 supersedes EN 13146-2:2002. The foreword states that detailed changes were made in this revision.

Which standards are used with SIST EN 13146-2:2012?

• EN 13481-1:2012 - provides the terms and definitions used in Clause 3.
• EN ISO 7500-1:2004 - sets the calibration and class requirements for the force-measuring system.
• EN ISO 9513:2002 - sets the calibration requirements for extensometers used when displacement is measured linearly.
• EN 13146 series - this part sits with the other fastening-system test methods, including longitudinal rail restraint, impact load attenuation, repeated loading, electrical resistance, severe environmental conditions, clamping force, in-service testing, and stiffness.
• EN 13481 series - these test methods support the performance requirements for fastening systems.

What does the SIST EN 13146-2:2012 document contain?

The document contains a defined laboratory method, equipment requirements, specimen requirements, a step-by-step procedure, and a reporting checklist. It also includes Figure 1 for the in-line test arrangement, Figure 2 for the offset fastening arrangement, and Annex A with a typical moment-of-load-displacement graph.

For testing, the important output is the graph of moment against rail angle, because that is where the 1° torsional resistance value is taken from. For engineering and product assessment, the report items and the controlled loading conditions make the results easier to compare across laboratories.