Physical and Mechanical Properties of Geosynthetic Clay Covers

Öz

Geosynthetic Clay Liners (GCL); is a material consisting of a fine granular powder or sodium bentonite placed between
two layers of a geosynthetic material, usually a geotextile or geomembrane. GCLs; The bentonite contained in the
geotextiles on both sides is bonded with an adhesive, needle punch or suture bonding. Needle punching causes some
fibers in the upper geotextile to extend into the bentonite and lower geotextile, binding the entire structure together. Fibers
pierced in the lower geotextile either rely on natural entanglement and friction to hold the GCL together, or are heated
and fused to the underlying geotextile, potentially creating a stronger bond between the two geotextiles and bentonite.
Bentonite is the most important component of GCLs and is a granular clay composed of highly adsorbing volcanic ash
(usually sodium bentonite). This material has high water retention and swelling potential. The hydraulic properties and
conductivity of GCLs vary depending on the quality of the clay used. The properties of bentonite clay can be enhanced
by adding other additives. In this paper, the physical and mechanical properties of GCL has been studied.

Anahtar Kelimeler

• Geosynthetic Clay Liners (GCL)
• Geocomposite
• Compressed Clay Layers (CCL)
• Geotextile (GT).

Geosentetik Kil Örtülerin Fiziksel ve Mekaniksel Özellikleri

Öz

Geosentetik Kil Örtüleri (GCL); genellikle bir geotekstil veya geomembran olan bir geosentetik malzemenin iki katmanı
arasına konan ince bir granüler toz veya sodyum bentonitten oluşan malzemedir. GCL’ler; her iki taraftaki geotekstillerin
içerdiği bentonit ile bir yapıştırıcı, iğneyle delme veya dikiş bağlama ile yapıştırılır. İğne delme işlemi, üstteki
geotekstildeki bazı liflerin tüm yapıyı birbirine bağlayarak bentonit ve alt geotekstile uzanmasına neden olur. Alt
geotekstilde delinen lifler ya GCL'yi bir arada tutmak için doğal dolanma ve sürtünmeye dayanır ya da ısıtılarak alttaki
geotekstile kaynaşarak potansiyel olarak iki geotekstil ve bentonit arasında daha güçlü bir bağ oluşturur. Bentonit
GCL’lerin en önemli bileşenidir ve yüksek oranda adsorbe eden volkanik küllerden oluşan (genellikle sodyum bentonittir)
granüler kildir. Bu malzeme yüksek su tutma ve şişme potansiyeline sahiptir. GCL’lerin hidrolik özellikleri ve iletkenliği
kullanılan kilin kalitesine bağlı olarak değişmektedir. Bentonit kilinin özellikleri başka katkı maddeleri de eklenerek
güçlendirilebilir. Bu makale kapsamında, geosentetik malzeme türlerinden olan Geosentetik Kil Örtüsü malzemesinin
fiziksel ve mekaniksel özellikleri ele alınmıştır. 

Anahtar Kelimeler

• Geosentetik Kil Katmanlar (GCL)
• Geokompozit
• Sıkıştırılmış Kil Katmanlar (CCL)
• Geotekstil (GT).

Kaynakça

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