Functions and Applications of Geotextiles

Geotextile is a multifunctional geosynthetic material whose core functions are isolation, filtration, drainage, reinforcement, and protection. It is often used in conjunction with geomembranes to achieve seepage prevention and is widely used in water conservancy, transportation, environmental protection, geotechnical and other engineering projects.

I. Core Role

Isolation: Separating soil, gravel, roadbed and ballast of different particle sizes/materials to prevent mixing, maintain structural integrity, and improve bearing capacity.

Filtration (reverse filtration) is permeable to water but impermeable to soil, allowing water to flow through while trapping fine particles, thus preventing soil erosion, piping, and blockage of drainage holes.

Drainage: Forms internal drainage channels to quickly drain water accumulated in the soil/structure, reducing pore water pressure and preventing softening and instability.

Reinforcement improves the tensile and shear strength of the soil, reduces uneven settlement, and enhances the stability of slopes, roadbeds, and embankments.

Seepage prevention (composite use) When combined with geomembrane, it not only protects the membrane but also forms a highly efficient seepage prevention system, which can be used for landfill, water conservancy seepage prevention, etc.

II. Typical Use Scenarios

1. Water Conservancy Projects

Dikes/Reservoirs: Dam body filtration, drainage, and reinforcement; composite seepage prevention on the water-facing side to prevent seepage and piping.

Rivers/Channels: Slope protection filtration, erosion prevention, and reduced seepage; bank reinforcement.

Seawalls/Reclamation Areas: Soft soil foundation reinforcement, wave protection, isolation, and drainage.

2. Transportation Engineering

Highways/Railways: Subgrade isolation, reinforcement, and drainage; ballast-subgrade isolation; anti-reflective cracking in existing road reconstruction.

Airport Runways: Foundation isolation, drainage, and reinforcement to improve pavement stability.

Slopes/Retaining Walls: Reinforcement and stabilization, reverse filtration and drainage, and erosion and landslide prevention.

3. Environmental Protection and Municipal Engineering

Landfill Sites: Forms an impermeable liner with HDPE membranes, filtering leachate and protecting the membrane.

Wastewater Treatment/Tailillation Dams: Impermeable liner, filtration, and prevention of pollution spread.

Underground Engineering/Tunnels: Drainage, isolation, support reinforcement, and leak prevention.

4. Geotechnical Engineering and Construction

Soft Soil Foundation Treatment: Reinforcement + Subbase Composite Layer, significantly improving bearing capacity and reducing settlement.

Rooftop Greening / Artificial Lakes: Isolation, drainage, seepage prevention, water retention, and soil protection.

Ecological Restoration: Slope stabilization, moisture retention, and assisted vegetation restoration.