Geomembrane patching? Landfill cooling?
Puncture protection?

Questions and answers from the GMA Techline

Geotextile filter
Are there any papers done on the use of a geotextile filter layer below a GCL or CCL? Your assistance in this regard will be much appreciated.

(Tian | South Africa)

Dear Tian,
Thank you for your question. I will answer in two parts:

(1) For a geotextile under a GCL, it is for no good reason that I can see because the lower component is already a geotextile. This geotextile can be as the designer desires and many types are available. The exception is
the product that has bentonite adhered to
the lower side of a geomembrane. If one
were concerned of it becoming fugitive,
a geotextile could be used, but not in the context of a filter. It is then functioning as a separator only.

(2) For a geotextile under a CCL, this last statement applies as well. For example: if a drainage layer was under the CCL (as in a double-lined system) and one was concerned with fugitive silt/clay particles contaminating it, a geotextile could certainly be beneficial but will function as a separation layer.

For me to go further, I would need the actual cross section you are considering.

Bob Koerner | GMA Techline