Overview
EN ISO 22074-2:2024 - “Railway infrastructure - Rail fastening systems - Part 2: Test method for longitudinal rail restraint” is the CEN-adopted version of ISO 22074-2:2021. This laboratory test standard defines how to measure the maximum longitudinal force a rail fastening can resist without non‑elastic displacement, the longitudinal stiffness of embedded (adhesive) rail systems, and the shear displacement / slip data needed for track‑bridge interaction calculations.
Key topics and requirements
- Test objectives
- Determine the maximum axial load before non‑elastic displacement (slip) occurs.
- Measure longitudinal stiffness for embedded/adhesive fastenings.
- Provide shear displacement and slip parameters required for track‑bridge interaction models.
- Test specimens
- Surface‑mounted rails (approx. 0.5 m length) or embedded rails with specified embedment length and spacing representative of the fastening category.
- Complete fastening assemblies (including baseplates and components) fixed to sleepers, bearers or ballastless elements.
- Apparatus and measurement accuracy
- Actuator capable of applying at least 25 kN axial force (higher for dual fastenings or embedded rails).
- Displacement sensors per ISO 9513 class 2, capable of ±0.05 mm resolution.
- Force measuring system meeting ISO 7500‑1 class 1.
- Calibration traceable to SI units.
- Procedure essentials
- Tests performed at (25 ± 5) °C, with components conditioned for ≥4 hours.
- Load vs displacement recorded; longitudinal restraint and stiffness derived from the load–displacement curve (including bilinear approximations where applicable).
- Visual inspection and standardized test report requirements.
Practical applications
- Provides standardized laboratory methods for:
- Product validation and type testing of rail fastening systems.
- Supplying input data for track‑bridge interaction and structural models (shear/slip behaviour).
- Comparing performance across fastening designs (mechanical, adhesive, continuous support).
- Useful for manufacturers, independent test laboratories, railway infrastructure managers, track designers and bridge engineers who require validated longitudinal resistance and stiffness data for design, specification and safety assessments.
Who should use this standard
- Rail fastening manufacturers (type approval and R&D)
- Accredited test laboratories and standards bodies
- Infrastructure owners and maintenance authorities (track and bridge interface)
- Track and bridge designers performing interaction analysis
Related standards
- ISO 22074‑1 (Vocabulary for rail fastening systems)
- ISO 7500‑1 (Calibration/verification of force measurement)
- ISO 9513 (Calibration of extensometer/displacement systems)
- Other parts of the ISO 22074 series for complementary test methods
Keywords: EN ISO 22074-2:2024, longitudinal rail restraint, rail fastening systems, test method, longitudinal stiffness, track‑bridge interaction, railway infrastructure.
