Geonets

:"Also see Geosynthetics."

Geonets were originally developed by Sir Bryan Mercer, of Netlon, Ltd. in the United Kingdom. Mercer patented the machinery and processing methods for the lightweight plastic nets commonly seen in supermarkets for carrying produce, fruits and vegetables. Experimentation with gradually thicker ribs in various configurations led to robust drainage nets of the type used in geosynthetic engineering. The first known use of geonets was in 1984 for the environmental application of leak detection in a double lined hazardous liquid waste impoundment in Hopewell, Virginia. Geonets are indeed grid-like materials but their use dictates a separate identity. The reason for their separate treatment from geogrids lies not in the material or its configuration, but in its function. Geonets are used for their in-plane drainage capability, while geogrids are used for reinforcement. It should be stated at the outset, however, that geonets are not weak, flimsy materials. They have reasonable tensile strength, but are used exclusively in drainage applications. Note that geonets are generally used with one or two geotextiles on their upper and/or lower surfaces to prevent soil intrusion into the apertures which would tend to block the in-plane drainage function of the material. Hence, they are often manufactured as a composite and are then referred to as a geocomposite but in so doing are best referred to as a drainage composite. They certainly deserve mention in their own right. They can also be used by themselves—for example, when placed between two geomembranes.