Geomembrane liners at the base of solid waste landfills must be protected from stones and other sharp objects to properly act as liquid barriers. In Germany, a special protection efficiency test was developed for the assessment of the anticipated performance of protective layers.
At the LGA-Geotechnical Institute, the efficiency of six different geosynthetic protective layers was studied by large scale performance tests. The basal liner system, consisting of a compacted clay liner, a 2.5 mm thick HDPE-geomembrane, the protective layers and 0.3 m drainage stone of 16 to 32 mm were submitted to a uniformly distributed load increased stepwise up to 800 kPa. After more than nine months loading, the geomembrane was exhumed and the deformations were examined by laser-measuring technique. The six protective layers lead to different results. All systems tested functioned successfully.
A comparison of the observed and the anticipated performance allows conclusions concerning the German protection efficiency test. The paper will briefly introduce the German protection efficiency test, describe the large scale tests and discuss the results.
Menu