Geosynthetics drainage

A 0.3-m-thick granular LDS drainage layer with a minimum hydraulic conductivity of 1 x 10 2 cm/s or a geosynthetic LDS drainage layer with a minimum hydraulic transmissivity of 3 x 10 3 m2/s. 

Lafleur J, Savard Y (1996) Efficiency of geosynthetic lateral drainage in northern climates. Transp Res Rec 1534 12... 

Palmeira EM, Gardoni MG. The influence of partial clogging and pressure on the behaviom of geotextiles in drainage systems. Geosynthetics International 2000 7 403-431. 

Similar to the filtration function, the requirements for drainage are soil retention, adequate flow capacity, and long term soil-to-geotextile flow equilibrium, in respect of minimum clogging of the pore spaces. Apart from the flow capacity within the plane of the geosynthetic material, the other aspects have been dealt with above. We will therefore now consider the inplane flow characteristics. 

Backfills for geosynthetic reinforced walls should be free draining,because unexpected failure of these structures can be caused by lack of control of groundwater or seepage. An appropriate geocomposite can therefore be incorporated horizontally and/or vertically to provide adequate drainage. 

Zhao, A and Montanelli, F. (1999), Effect of soil presence on flow capacity of drainage geocomposites under high normal loads Geosynthetics 99, Conference Proceedings, Vol. 2, pp. 783-798. 

The fields of application of geosynthetics can be eharacterised by the terms separation, protection, filtration, drainage, reinforcement, containment and sealing. 

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