Selecting the correct geotextile is an engineering decision, not a commodity purchase. The product's geotextile specifications, detailed in a technical data sheet (TDS), are your blueprint for performance. Understanding these key properties ensures the fabric will function as intended throughout the design life of your project.
Here’s a breakdown of the most critical geotextile properties:
Physical Properties:
Mass Per Unit Area (Weight): Measured in g/m² or oz/yd². Generally indicates thickness and robustness. Heavier fabrics typically offer higher survivability.
Thickness: Measured under a specific pressure (mm). Important for cushioning and drainage capacity.
Mechanical Properties (Strength & Survivability):
Tensile Strength and Elongation: The force required to break a sample (kN/m) and the strain at break (%). Woven fabrics have high strength, low elongation. Nonwovens have lower strength, higher elongation.
Puncture Resistance (CBR or Pyramid): Measures resistance to penetration by a blunt or sharp object (N or lb). Critical for protection applications.
Tear Resistance: Resistance to propagating a tear (N). Indicates survivability during installation.
Grab Strength: A common tensile test method (ASTM D4632).
Hydraulic Properties (Flow):
Apparent Opening Size (AOS): The approximate largest soil particle that will effectively pass through the fabric (e.g., O95). Crucial for filter design to prevent soil loss (piping) or clogging.
Permeability (Water Flow Rate): The rate at which water flows perpendicularly through the fabric (l/m²/s). Must be greater than the soil's permeability.
Transmissivity (In-Plane Flow): The rate at which water flows within the plane of the fabric (l/m/s). Key for drainage geotextiles.
Endurance Properties:
UV Resistance: Indicates the retention of strength after a set period of UV exposure (e.g., 500 hrs). Important for exposed applications.
Other vital information includes roll size (width and length), relevant geotextile standards (ASTM, ISO, GRI), and installation guidelines. Always compare the project's design requirements against the TDS values, applying appropriate reduction factors for safety.
Partnering with a manufacturer that provides comprehensive, honest data sheets is crucial. At www.hzgeotextile.com, we provide detailed TDS for every product, allowing engineers and specifiers to make confident, performance-based selections. Our technical team is ready to help you interpret these geotextile specifications for your specific project conditions.
