Functions of geosynthetics containment fluid barrier and protection

7 Functions of geosynthetics containment (fluid barrier) and protection 

The % Strain(y.axis) is determined similarly and the average of two percentage strains is taken as the % strain of the indentation. It is recommended that the average % strain should be determined for each of the three largest identifiable indentations in the lead sheet. For effective protection of a geomembrane the average % strain for each of the three selected indentations should be less than 0.25%.  

The above test is a direct assessment of the likely performance of a geotextile with limestone aggregate. Other soils can be used for assessment relevant to the installation site. An alternative approach used as a comparative measure of geotextile protectors is to replace the soil layer with a layer of 20 mm diameter steel ball bearings. In this test the geomembrane is omitted from the arrangement in Fig. 8.14a, since the objective is to determine the resistance to a uniformly localised compression. 

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