Geosynthetics form a family of many different products widely used in civil engineering projects. They are defined in an international standard, EN ISO 10318 [1], as “a product, at least one of whose components is made from a synthetic or natural polymer, in the form of a sheet, a strip or a three-dimensional structure, used in contact with soil and/or other materials in geotechnical and civil engineering applications”. In other words, they are special types of textiles being used in civil engineering projects for different purposes that this note will cover.

They are divided into two large families:

• geotextiles and geotextile-related products, which are permeable products (ie water can flow thru them). Geotextiles are further defined as “planar, permeable, polymeric (synthetic or natural) textile material, which may be nonwoven, knitted or woven” [1]. They represent the main class of geosynthetics because they are by far the mostly used products in terms of surface covered. Geotextiles were also the first member of the family and appeared in the 1960s, with renowned products such as BiDim (for bi-dimensional) developed by Rhone-Poulenc in France.
• geomembranes and bentonitic geosynthetics, which are essentially waterproof.

Geosynthetics can also be geocomposites, meaning they are “manufactured, assembled material using at least one geosynthetic product among the components” [1].

Many different products are therefore part of the large family of geosynthetics; geotextiles, geosynthetic barriers (including clay geosynthetic barriers), geomembranes, geogrids, geonets, geocells and geomats are all examples of geosynthetics (Figure 1 - [2]).