Through the synergistic effects of reinforcement, separation, confinement, and drainage, geogrids significantly enhance subgrade bearing capacity, control differential settlement, and suppress reflective cracking. They are widely applied in soft soil, permafrost, saline-alkali ground, and widened road splice sections. This article systematically elaborates on the reinforcement mechanism, material selection, laying process, and quality control to provide technical support for long-term subgrade stability.

I. Reinforcement Mechanism

  • Friction and Interlock: Geogrid ribs interlock with soil particles, transferring stress and distributing loads.
  • Confinement Effect: Restricts particle displacement, enhancing overall rigidity and shear strength.
  • Separation and Uniformization: Separates soft and hard soil layers, preventing interlayer instability and uneven settlement.
  • Stress Dissipation: Reduces stress concentration at crack tips, suppressing reflective cracking in pavement surfaces.

II. Product Selection and Application Scenarios

  • Biaxial Plastic Geogrid: Suitable for soft foundation subgrades, abutments, and general embankments, with tensile strength of 20–80 kN/m.
  • Steel-Plastic Geogrid: Designed for heavy-duty roads, high fills, and tailings dams, with tensile strength of 80–200 kN/m.
  • Fiberglass Geogrid: Used for asphalt pavement crack prevention, featuring high modulus, low elongation, and high-temperature resistance.

III. Key Construction Processes

  • The base surface must be leveled and compacted, free of sharp hard objects. The geogrid shall be laid flat and taut, without wrinkles or distortion.
  • Overlapping: Longitudinal overlap ≥ 30 cm, transverse overlap ≥ 20–50 cm, secured with U-shaped anchors at 1.5–2.0 m intervals, with denser anchoring at edges.
  • Backfill must be completed within 48 hours after laying. The protective layer thickness shall be ≥ 20 cm. Direct vehicle rolling on the geogrid is prohibited. Fill material particle size shall be ≤ 6 cm.

IV. Engineering Performance

  • Soft foundation bearing capacity increased by 40%–100%, differential settlement controlled within ≤ 9 cm.
  • Reflective cracking reduced by 70%–90%, maintenance costs decreased by over 50%.
  • Improved integrity of splice sections in road widening projects, with post-construction settlement meeting specification requirements.

Geogrid reinforcement technology offers fast construction, low cost, and long service life, making it a standard solution for transportation infrastructure and site reinforcement, adaptable to various geological conditions both domestically and internationally.