Geosynthetic Clay Liner (GCL) Overview

In construction, it is common to build containment areas. These containment areas may hold liquids, gases or solids, either to store the material or to prevent it from polluting the surrounding environment. In Indonesia, containment projects generally use a geosynthetic product called geomembrane, although a GCL (geosynthetic clay liner) is an increasingly popular alternative.

Geomembrane is impermeable, which makes it well suited to containment and to preventing seepage on construction sites. However, geomembrane also has a weakness in these conditions. The most common weakness of geomembrane is that it is prone to puncture.

Geomembrane will be punctured and start leaking when it comes into contact with sharp materials, so it is usually used together with geotextile. The geotextile resists these punctures so that they do not directly damage the geomembrane.

Geosynthetic Clay Liner Overview

Besides geomembrane, there is another geosynthetic product that can be an alternative for containment areas: the Geosynthetic Clay Liner (GCL). A Geosynthetic Clay Liner works as a waterproof layer like geomembrane, offers puncture resistance and has self-repair capability. A Geosynthetic Clay Liner is a geosynthetic made from two geotextiles: a woven geotextile and a non-woven geotextile.

Between these two geotextiles is a layer of bentonite powder. The bentonite only works once it has absorbed water and swelled. Swollen bentonite becomes a waterproof layer with self-repair capability. This self-repair function comes into play when the bentonite layer is damaged: the bentonite swells and fills the damaged spot.

Installing a Geosynthetic Clay Liner is not much different from installing geomembrane. An anchor area of about 2 meters and an overlap area for joining the Geosynthetic Clay Liner panels must be prepared. Unlike geomembrane, which needs welding rod and a geomembrane welding machine to make seams, a Geosynthetic Clay Liner only needs bentonite powder mixed with water into a clay-like paste, which is used to bond the panels together. This makes the Geosynthetic Clay Liner simpler to install and join.