Geotextiles and related products may be used in a wide range of applications where they may be required to perform one, or a combination, of design functions. Different functions, and different operational environments, will make different demands on the geotextile.
In general the two broad requirements of a geotextile are that it must be robust enough to survive short term environments as well as maintaining adequate properties in the long term to fulfill the required design function .
In civil engineering structures a geotextile performs mechanical functions such as separation and reinforcement and hydraulic functions such as drainage and filtration either separately or simultaneously. Beside these functions there are two other functions ,these are water proofing and protection.