Fig. 1

The use of a GCL to prevent water loss in these applications is shown in Fig. 1. Since the confining stress is typically low (less than in 50 kN/m²) in these applications the GCL performance is dominated by the hydraulic water head. The stability of the GCL is influenced by the slope angle , the normal load gradients, and the interface friction angle , with adjacent layers. The erosion stability of the bentonite layer (during wave action of the water) as well as the bentonite piping (affected by the high hydraulic water head and the subsoil conditions) are main issues to consider during these applications. Freeze/thaw effects are typically only to be considered in areas of concern. Dry/wet effects are in this application not of a large issue since the bentonite of the GCL has a high suction capacity and is wet in areas which lay above the water level and therefore over the area to be sealed.

Bentofix® GCLs with one woven and nonwoven component are best suited for this application if the cover material and subsoil are sandy. In other cases more robust geotextile components may be suitable such as double sided nonwovens. Bentofix® GCLs with a nonwoven on both sides typically allows steeper designs than with woven components, due to an increase of the interface friction angle and Bentofix® with a nonwoven/woven composite as carrier perform best against bentonite erosion.