Overview
EN ISO 13428:2024 - Geosynthetics: Determination of the protection efficiency of a geosynthetic against impact damage (ISO 13428:2024) describes a standardized index test (and optional performance test variant) to quantify how effectively a geosynthetic protects a hard surface from impact by a hemispherical object. The method measures the change in thickness of a thin lead plate placed between the geosynthetic specimen and a rigid support after a controlled impact. The standard applies to geosynthetics with apertures smaller than 15 mm.
Key topics and technical requirements
- Test principle: A hemispherical steel probe impacts a geosynthetic specimen lying on a rigid steel support with a thin lead plate between them; residual lead thickness indicates protection efficiency.
- Index test parameters:
- Probe: steel cylinder with a hemispherical head (20 ± 0.5 mm diameter).
- Index probe mass and drop height: (1 000 ± 2) g falling from (1 000 ± 10) mm (for index tests).
- Lead plate: standardized thin lead sheet (thickness updated to 2.0 mm in the 2024 revision).
- Specimens:
- Five specimens per face, square shape, minimum 60 mm × 60 mm.
- A single lead plate may be used for all five impacts.
- Conditioning: Specimens conditioned in the standard atmosphere for testing at (20 ± 2) °C and (65 ± 5) % RH (ISO 554); conditioning considered complete when successive mass changes ≤ 0.25%.
- Measurements and reporting:
- Initial and residual lead plate thickness measured (initial under 2 kPa).
- Impact energy calculated as E = F × h (weight × drop height).
- Test report includes specimen details, test parameters, residual thickness and calculated protection efficiency.
- Performance test option: Procedures can be adapted to use the real rigid surface and the actual geosynthetic sequence representative of in-service conditions (see Annex A).
Applications and users
- Practical for assessing protection of:
- Coatings on steel pipelines (geonets, geotextiles).
- Geomembranes behind concrete retaining walls (geocomposites, geospacers).
- Any installation where stone or debris may cause impact during backfilling.
- Typical users:
- Geotechnical and civil engineers, pipeline designers, geosynthetic manufacturers, quality control laboratories, and specification authors who need objective, repeatable data on impact protection performance.
Related standards
Normative references frequently used with EN ISO 13428:2024:
Keywords: EN ISO 13428:2024, ISO 13428, geosynthetics, impact damage, protection efficiency, index test, performance test, lead plate, geotextiles, geomembrane, geonets.