Overview
EN ISO 22074-8:2024 - "Railway infrastructure - Rail fastening systems - Part 8: Test method for vertical stiffness" (identical to ISO 22074-8:2022) specifies laboratory test procedures for measuring the static and low‑frequency dynamic vertical stiffness of rail pads, baseplate pads and complete rail fastening assemblies. Published by CEN in March 2024 and adopted from ISO, the standard is part of the ISO 22074 series for rail fastening systems and defines methods, apparatus checks and reporting requirements for laboratory evaluation.
Key topics and requirements
- Scope and definitions: Clear terminology for static stiffness and low‑frequency dynamic stiffness, and reference to ISO 22074‑1 for vocabulary.
- Verification of calibration: Requirements to verify force and displacement measuring systems using relevant calibration standards (normative references include ISO 7500‑1 and ISO 9513).
- Test procedures for pads (Clause 6):
- Static test procedure: principle, required apparatus, stepwise test procedure and mandatory elements of the test report.
- Low‑frequency dynamic procedure: frequency‑based measurement approach, apparatus and report format.
- Test procedures for complete rail fastening assemblies (Clause 7):
- Static and low‑frequency dynamic procedures tailored to assemblies, including specimen preparation, apparatus and reporting.
- Symbols and measurement parameters: Standardized notation for forces, displacements and stiffness (e.g., F, d, k) to ensure consistent data exchange.
- Frequency limitation: Methods cover static and low‑frequency dynamic tests only; frequencies above 30 Hz are excluded (see other standards for high‑frequency testing).
Practical applications and users
EN ISO 22074‑8:2024 is intended for:
- Manufacturers of rail pads, baseplate pads and fastening assemblies - for product development, design validation and quality control.
- Independent testing laboratories - to perform standardized vertical stiffness measurements and generate traceable test reports.
- Railway infrastructure owners and operators - to assess component performance, support procurement specifications and ensure interoperability.
- Track engineers and consultants - to select and validate fastening systems that meet vertical stiffness requirements for track design and maintenance.
- Regulatory and conformity assessment bodies - for verification and certification of fastening components.
Practical uses include comparative product testing, acceptance testing during procurement, research on track dynamic behavior, and inputs to track design models.
Related standards
- ISO 22074‑1 (vocabulary for rail fastening systems)
- ISO 7500‑1 (calibration and verification of force measurement)
- ISO 9513 (extensometer calibration)
- For higher‑frequency stiffness testing: EN 15461 and EN 17495
Keywords: EN ISO 22074-8:2024, rail fastening systems, vertical stiffness test, rail pads, baseplate pads, static stiffness, low-frequency dynamic stiffness, railway infrastructure standard.
