What is a Biaxial geogrid?
Biaxial geogrids are grid-like geosynthetics made from polypropylene (PP), high-density polyethylene (HDPE), or other polymers through processes such as extrusion, punching, and biaxial stretching.
"Biaxial" means:
It possesses high and similar tensile strength in both the longitudinal (warp) and transverse (weft) directions.
Structural Features
Composed of regular square or rectangular meshes with strong nodes and evenly spaced ribs, this grid structure creates an interlocking effect with soil particles, preventing lateral displacement of soil particles. The combined action of the nodes and ribs enhances the integrity and bearing capacity of the foundation soil.
Functional Positioning
Biaxial geogrids are often used in combination with fillers (sand, gravel, etc.) to form a "grid-soil" composite structure, significantly improving overall performance.
Typical Performance Parameters
Tensile Strength: 20–50 kN/m (some high-strength types can reach over 80 kN/m)
Elongation at Break: ≤13%
Joint Strength: Close to or equal to the parent material strength
Durability: Acid, alkali, UV, and aging resistant, with a service life of decades
Performance characteristics of biaxial geogrid
High Tensile Strength
Balanced Longitudinal and Transverse Directions: High tensile strength in both the warp and weft directions, typically 20–50 kN/m, with some high-strength products reaching 80–100 kN/m.
Strong Mechanical Stability: Capable of withstanding bidirectional loads and stress distribution under complex working conditions, preventing uneven deformation of the foundation soil.
Low Elongation
The elongation at break is typically ≤ 13%, meaning the material deforms minimally when subjected to stress.
Strong interlocking and restraining effects
The biaxial geogrid has a regular mesh structure that creates an interlocking effect with soil and rock particles.
It effectively restrains the lateral displacement of soil particles;
It improves the integrity and friction of the filler;
It enhances the bearing capacity of the composite.
Durability and Environmental Adaptability
Chemical Corrosion Resistance: Excellent resistance to acids, alkalis, salts, and various underground chemicals.
UV-Resistant: Suitable for long-term exposure.
Low-Temperature Resistance: Maintains stable performance in temperatures ranging from -50°C to +60°C.
Long Service Life: 30–50 years of stable use under normal operating conditions.
Function and effect of biaxial geogrid
Reinforcement
Biaxial geogrids significantly enhance the overall strength of the fill and soil.
The interlocking effect constrains lateral displacement of soil particles, improving the bearing capacity of the foundation.
They are commonly used for soft soil foundation treatment, roadbed filling, and piled slope reinforcement.
Load Distribution
The grille mesh distributes concentrated loads from vehicles and structures over a wider area.
This prevents sinking or cracking caused by excessive localized stress.
Settlement Control
Using biaxial geogrids on soft foundations can significantly slow settlement.
Laying multiple layers of geogrids can also control differential settlement and ensure roadbed flatness.
Improving Slope and Embankment Stability
By strengthening soil integrity and shear strength, this improves slope stability.
This helps prevent embankment slippage and riverbank collapse.
Application Areas
Highway and railway engineering: roadbed reinforcement, roadbed stabilization, and settlement control.
Water conservancy and port engineering: embankment reinforcement, revetment protection, and port yards.
Municipal and construction engineering: parking lots, plaza foundations, and underground engineering excavations.
Mining and energy engineering: mining roads, slag dams, and tailings ponds.
Ecological and environmental protection engineering: landfills, river management, and mountain stabilization.
Biaxial geogrids have high bidirectional strength, low elongation, excellent interlocking effect and long-term durability. They play an irreplaceable role in the construction of infrastructure such as roads, railways, water conservancy, municipal administration, and mining. Biaxial geogrids are an effective tool for solving foundation stability and bearing capacity problems, and are an important part of future green infrastructure and smart projects.
