Drainage is the collection of precipitation, groundwater and other liquids or gases which have to be discharged. Drainage systems are supplied as single elements or composites consisting of at least one filtering layer and one percolation layer. The latter takes up the liquid and discharges it with a minimum loss of pressure. Surface
drainage systems are frequently combined with sealing systems, e. g. in landfills, and waterproofing applications, like underground car parks or tunnels. Geosynthetic drainage systems substitute expensive mineral
drainage layers.



In order to allow long-term drainage performance of the percolation
layer, filter geotextiles are deployed to transmit shear stress on the
percolation layer. Mechanically bonded nonwovens (see filtration) are
especially suitable for filtration functions. Randomly entangled mesh
matrices are especially suitable as drainage layers since they have a
stable three-dimensional static structure. Shearing stresses can be
transferred without damage, and thus the long-term hydraulic performance
is maintained.

IVG logo Interessenverband Geokunststoffe