Functions of geotextiles

Four discrete functions define the mode of functioning of a geotextile in any application;

1. Separation

Geotextiles are commonly used in road construction because of their separating properties. Geotextiles could prevent the intermixing of two neighbouring soils.  The geotextile, for example, retains the drainage and strength characteristics of the aggregate material by separating fine subgrade soil from the aggregates of the base course.

 Some of the applicable areas are:

• Between subgrade and stone base on unpaved and paved roads and airfields.

• Between subgrade in railroads.

• Between landfills and stone base courses.

• Between geomembranes and sand drainage layers.

2. Filtration

The geotextile-to-soil system equilibrium provides adequate liquid flow with little soil loss across the geotextile’s plane. The key features of geotextiles that involve infiltration action are porosity and permeability.

3. Reinforcement

In the same way that steel raises the tensile strength of concrete, geotextile increases the tensile strength of the soil. The following three mechanisms account for the increase in soil strength as a result of the installation of geotextiles.

• Interfacial friction between the geotextile and the soil/aggregate provides lateral constraint.
• Forcing a greater shear strength surface to grow on the possible bearing surface failure plane.
• Membrane type of support for the wheel loads.

4. Sealing 

A layer of non-woven geotextile is placed between the existing and new asphalt layers. The geotextile absorbs asphalt and transforms into a waterproofing membrane, preventing water from flowing vertically into the pavement structure.

Wall Tag is one of the leading suppliers of various types of geotextile membranes in Singapore with a strong sales and service network availability to cater to their clients.