This standard outlines the general characteristics and standardized laboratory test methods for evaluating geogrids used in geotechnical applications. It provides procedures for determining key performance indicators such as wide-width tensile strength, junction strength, installation damage resistance, and creep. This code is essential for quality assurance, product comparison, and providing input data for geotechnical design.
Specifies general characteristics, terminology, sampling and methods of test for geogrids.
Quick Reference Values
Standard conditioning temperature27 ± 2 °C
Standard conditioning relative humidity65 ± 5 % RH
Specimen width for wide-width tensile test200 mm
Strain rate for wide-width tensile test10 ± 3 %/min
Minimum specimens for wide-width test5 per direction
Minimum gauge length for tensile test100 mm
Key Formulas
Tensile Strength (T) = F_peak / W — where F_peak is peak load, W is initial specimen width
Strain (ε) = (ΔL / L₀) × 100% — where ΔL is extension, L₀ is initial gauge length
Practical Notes
The wide-width tensile test (Annex A) is critical as it better represents in-situ stress conditions for geogrids compared to narrow strip tests.
Ensure proper specimen clamping to prevent slippage, a common source of error that yields artificially low strength results.
Installation damage resistance (Annex C) is a vital test simulating the effect of backfill placement and compaction, which directly impacts the geogrid's long-term design strength.