Geosynthetics

Geosynthetics are produced in different shapes and materials, each of which is used for almost the same use. The word geosynthetics is used for a group of products that are commonly used to solve geotechnical problems. The word is generally used for eight products: geotextiles, geogrids, geomembranes, geontsgeofoams, geocells and geocomposites. Their polymeric nature makes them suitable for use on the ground, where they are expected to be very durable. These products have a wide range of applications and are currently used in many civil applications, geotechnical, transportation, environmental, hydraulic, and private development applications such as roads, airports, railroads, earth dams, retaining walls, Water storage pools, dams, canals, erosion control, sediment control, landfill bedding, landfill cover, mines, aquaculture and agriculture are used.

Geosynthetics are divided into several general groups:

Geotextiles

For reinforcement, separation, proper drainage, increasing the bearing capacity of asphalt and soil, increasing the useful life of asphalt, protection of structures from shores and ports, homogeneous subsidence in marine structures such as breakwaters, protection of eroding ground, protection of ballast layer in railways, it is used to increase the bearing capacity of the railway track, protect the geomembrane layers and many other things. Geotextiles are usually produced in the form of woven or non-woven fabric. Woven geotextiles are made by weaving vertical and horizontal strands, the end result of which is the creation of a durable layer, something like fabric. Nonwoven geotextiles are produced in different ways. Common methods include heat bonded, needle punched (mechanically shaped or needle-shaped) and chemically bonded (chemically shaped). Woven and non-woven geotextiles are generally composed of filamentary fibers and fibers, which are composed of polypropylene, polyester, polyethylene and polyamide. There is a small group of geotextiles that are composed of fibrous fibers and are mainly used in the field of erosion control.

Geogrid

They are used for soil reinforcement and construction of retaining walls, and etc. Geogrids are lattice grids that are used as horizontal columns to hold walls in place. Geogrid is like a shield to withstand the vibrations of the outer surface of the soil. The geogrid keeps the soil constant so that the strength of the walls built on it is increased. This product is mostly used in retaining walls and road construction and is produced from materials such as polyethylene, polyester, fiberglass and … with different properties.

Geomembrane

Geomembrane is a sheet made of polyethylene, PVC, etc., which has the property of insulating all types of surfaces without the need for special substructure. They are impermeable to a variety of fluids (eg water, chemicals and petroleum) and are used for sealing, artificial lakes, fish ponds and industrial ponds, sewage lagoons and water and sewage pipes. Geomembrane can be installed alone or with a variety of coatings, such as concrete slabs or gravel. Among the applications of this product, it is used to improve the quality of old dams, insulation, prevent leakage in the floor of tanks, water structures, etc. The life of uncoated geomembranes is slightly shorter than that of coated geomembranes because they are exposed to UV, but on the contrary, they are easier to repair than coated ones. On the other hand, coated geomembranes are more at risk of perforation. Geotextiles are usually placed below and above the geomembrane to protect it from perforation. It also strengthens the load-bearing capacity of the structure and the geomembrane. In this case, the geotextile acts as a shock absorber, reducing the concentration of stresses on the geomembrane layer.

Geonts

They are suitable for preventing erosion of slopes and drainage. Geonts are a class of geosynthetics produced by the continuous injection of polymeric strips at a precise angle to each other. They are usually made of polyethylene. The distance between the disciplines of this class of geosynthetics has created very favorable conditions for the use of geonts as an optimal means of drainage. Geotns are available in different pore sizes and are selected according to the size of soil particles to allow drainage without moving the soil particles. Hence, the main function of the junction is drainage. However, according to studies, due to the lower price of geotextiles for drainage, geotextiles are more used than geonts.

Geocomposites

They are a combination of different geosynthetic sheets such as geotextile-geont, geotextile-geogrid, geotextile-geocell, etc. and in many cases are used as filters-drainage. Popular types are commonly used to drain sports fields and retaining walls and tunnel roofs.

GCL

GCL or general liner geosynthetics according to the definition of geocomposite is actually a type of geocomposite, but due to its widespread use and similar function, geomembranes are considered separately and consist of geosynthetic sheets with interlayer (bentonite) and to prevent Water leakage and sealing are used. The common type consists of a layer of bentonite between two sheets of geotextile or between a layer of geotextile and geomembranes. The special advantage of GCL is its self-healing and fusion properties.

Geocell

These materials are made of a three-dimensional network of non-woven polyesters and are used to prevent erosion and control the erosion of slopes.

Geomat

This product, which is very similar to geocell in terms of application, is made of polypropylene and is used to prevent soil erosion, soil leaching by water and sloping soils.