Field evaluation of hydraulic performances of geosynthetic clay liners by small and large-scale tests

This paper describes some devices to assess hydraulic performances of geosy nthetic clay liners and presents the results of field tests in different de sign configurations. Some large- and small-scale experiments are presented hereby in order to characterise these products under real condition of soli citations. This approach contrasts with traditional laboratory tests perfor med for construction quality management. Three main methods are presented. The first method consists of a field hydraulic conductivity test comparable to those made for clay liners. This short-term/short-scale device is adapt ed for thin liners mainly for quality control purposes. The second method w as developed to follow quite long-term performances of GCL against water in take. A last method, based on lysimeter technology, allows a long-term and large-scale monitoring of GCLs with leakage collecting system. Many results obtained from field experimentation managed in France are presented and co mmented. (C) 2000 Elsevier Science Ltd. All rights reserved.