Overview
EN ISO 10468:2023 / ISO 10468:2023 specifies standardized test methods to determine the ring creep properties of glass‑reinforced thermosetting plastics (GRP pipes) under wet or dry conditions. The standard defines how to measure key long‑term mechanical behaviours – notably the creep factor and the long‑term ring creep stiffness – using ring‑type test pieces subjected to vertical compressive loading. Wet testing is performed by total immersion in water to simulate in‑service conditions; dry testing is typically used for raw material consistency and quality control.
Key topics and technical requirements
- Measured properties
- Creep factor (αx,creep): ratio of long‑term ring creep stiffness to initial ring stiffness at a defined reference position.
- Long‑term ring creep stiffness (Sx,1,creep): extrapolated ring stiffness at a reference position (position 1) for a defined exposure time x.
- Test conditions
- Wet testing: total immersion in water to simulate long‑term service exposure.
- Dry testing: controlled dry environment for material consistency checks.
- Apparatus and test set‑up
- Compressive loading machine, specified force application surfaces (plates or beam bars), water container for immersion, and precision measuring devices for deflection/time or stiffness/time.
- Specimen preparation and conditioning
- Requirements for test piece dimensions, number of specimens, and pre‑conditioning prior to testing.
- Procedure and calculations
- Defined test procedures for constant load testing, measurement of deflection or stiffness over time, extrapolation methods for long‑term performance, and reporting requirements (option to plot deflection vs time or stiffness vs time).
- Reference measurements
- Initial ring stiffness is determined in accordance with ISO 7685, and regression/extrapolation methods reference ISO 10928.
- Reporting
- Mandatory test report items include specimen details, test conditions (wet/dry), measured data, extrapolation method, and calculated creep factor and long‑term stiffness.
Applications
- Performance verification and lifetime assessment of GRP pipes in potable water, wastewater, irrigation, industrial fluid transport, and buried piping systems.
- Quality control and raw material consistency checks during manufacturing (dry creep tests).
- Design input for structural and hydraulic engineers assessing long‑term deformation under external loads.
- Product certification, procurement specifications, and compliance testing for standards and regulations.
Who should use this standard
- GRP pipe manufacturers and R&D laboratories
- Independent testing and certification bodies
- Civil, mechanical and pipeline design engineers
- Quality assurance teams, procurement officers, and regulators
Related standards
- ISO 7685 - Determination of initial ring stiffness (referenced for S0)
- ISO 3126 - Dimensional determination of plastic piping components
- ISO 10928 - Regression analysis methods for extrapolation
Keywords: GRP pipes, ring creep properties, creep factor, long‑term creep stiffness, EN ISO 10468:2023, wet and dry creep testing, ring stiffness, testing methods, quality control, pipe design.
