In projects such as subgrade reinforcement, slope protection, retaining wall construction and asphalt pavement reinforcement, geogrid sizes directly determine reinforcement performance, construction efficiency and cost control. Many engineers and purchasers struggle with matching standard apertures, roll widths and lengths to actual applications. Based on industrial standards and practical experience, this article systematically explains the geogrid size system, classified specifications and selection methods to help you quickly choose the suitable model.
Key Geogrid Size Terminology
Geogrid size consists of three major dimensions: aperture size, roll dimensions and rib specifications, which are also related to tensile strength and serve as core parameters for engineering design and procurement.
Aperture size refers to the internal opening dimensions, which directly affect soil interlock and drainage performance.
Roll width and length determine the coverage area per roll and influence joint quantity and construction efficiency.
Rib width and thickness are related to tensile strength; wider ribs deliver higher bearing capacity.
Clear understanding of these terms prevents potential engineering risks caused by incorrect size selection.
Standard Sizes of Different Geogrid Types
Geogrids are divided into five categories: biaxial plastic, uniaxial plastic, fiberglass, steel-plastic composite and polyester warp-knitted. Each type follows universal industrial standard sizes for different loads and scenarios.
Biaxial plastic geobiaxial geogridgrid
Made of PP or PE, it is widely used for subgrade reinforcement. Common apertures include 25.4mm, 50.8mm and 125mm. Standard roll width is 2–6m, length 50–100m, tensile strength 15–50kN/m. Suitable for municipal roads, parking lots and soft ground improvement.
Uniaxial plastic geogrid
Made of HDPE with high unidirectional tensile strength. Typical apertures are 76.2mm and 101.6mm. Roll width 1–4m, length 50–100m, tensile strength up to 80–320kN/m. Designed for reinforced retaining walls, high-fill slopes and steep slope protection.
Fiberglass geogrid
Features high temperature resistance and low deformation. Small apertures of 12.7mm, 25.4mm and 40mm are common. Roll width 1–6m, length 50–100m, tensile strength 30–120kN/m. Mainly used for asphalt pavement crack resistance, road reconstruction and airport runway reinforcement.
Steel-plastic comcomposite geogridposite geogrid
Composite of steel wire and plastic, with high strength and low creep. Apertures 25.4mm and 50.8mm. Roll width 1–6m, length 50–100m, tensile strength 30–120kN/m. Suitable for heavy-duty projects including highways, railway subgrades and large retaining walls.
Polyester warp-knitted gepolyester geogridogrid
Acid and alkali resistant with high durability. Apertures 12.7mm, 25.4mm and 50.8mm. Roll width 1–6m, length 50–100m, tensile strength 15–800kN/m. Applied in dams, tailings ponds and coastal anti-corrosion projects.
3-Step Geogrid Size Selection Guide
Step 1: Determine Aperture Size by Project Scenario
Small apertures (≤25.4mm) are ideal for asphalt pavements and airport surfaces to lock fine aggregates and prevent cracking.
Medium apertures (25.4–50.8mm) suit municipal roads and subbase layers, balancing interlock and drainage.
Large apertures (≥76.2mm) are used in retaining walls, slopes and gravel layers for better permeability and stability.
Step 2: Select Roll Dimensions by Construction Conditions
For large areas such as subgrades and dams, 4–6m wide rolls are preferred to reduce joints.
For narrow spaces like tunnels, 1–2m narrow rolls are easier to handle and install.
Standard roll length is 50–100m, customizable for transportation and construction schedules.
Step 3: Match Sizes to Design Tensile Strength
Light-duty projects (residential roads, yards): 15–30kN/m.
Medium-duty projects (urban arterial roads, general slopes): 30–80kN/m.
Heavy-duty projects (highways, railways, high retaining walls): over 80kN/m with matching rib width.
Frequently Asked Questions
1. What is the most commonly used standard geogrid aperture?
25.4mm is the universal industrial size, suitable for most roads, subgrades and slope projects.
2. Can geogrid sizes be customized?
Yes. Roll width can be adjusted between 1–6m, apertures can be customized for specific soil particle sizes. Custom lengths are also available with minimum order quantity and lead time.
3. How does aperture size affect geogrid performance?
An overly small aperture hinders drainage and may soften the subgrade. An overlarge aperture reduces soil interlock and weakens reinforcement. A general rule is that soil particle size ≤ 1.5 × aperture size.
4. What is the difference between size and specification?
Size refers to physical dimensions including aperture, width and length. Specification includes complete parameters: size, material, tensile strength and standard, e.g. biaxial plastic geogrid 30kN/m.
Conclusion
The core logic of geogrid size selection is:
Aperture matches soil and scenario, roll dimensions fit construction conditions, strength meets load requirements.Following standard size specifications and project-based matching ensures optimal reinforcement performance, construction efficiency and cost control.
For precise selection, refer to standards such as GB/T 17689 and JT/T 1432.1, or consult professional manufacturers for customized solutions based on geological conditions, design loads and construction requirements.
References
- GB/T 17689-2008 Geosynthetics–Plastic Geogrids: This standard specifies the terminology, dimensions and properties of plastic geogrids.
- JT/T 1432.1-2022 Geosynthetics for Highway Engineering–Part 1: Geogrids: This standard specifies the selection and dimension application of geogrids in highway engineering.
- QB/T 2854-2007 Test Method and Evaluation for Creep of Plastic Geogrids: This standard provides the test method for creep performance of geogrids.
- GB/T 15788-2017 Geosynthetics–Wide-Width Tensile Test Method: This standard defines the unified test method for tensile strength.
