Modelling a geosynthetic clay liner in a centrifuge and its application to the dynamic stability of small-sized earth-fill dams

Abstract

This study proposes a centrifuge modelling method for geosynthetic clay liners (GCLs). The development of such a centrifuge model has been challenging due to the complex hydraulic and mechanical behaviour of GCLs and their interface with the soil. Additionally, the proposed method was applied to the seismic stability of an earth-fill dam. Impermeable sheets were selected as the GCL model based on validation using finite element seepage analysis and similarity laws. Dynamic centrifuge model experiments were conducted on a 10-m-high embankment with a high phreatic line to visually verify the failure mechanism, as previous full-scale tests did not provide clear visualisation. A transparent plate imaging confirmed upstream translational failure of the GCL, which was installed in a staircase shape. With regard to improving the seismic resistance of the embankment, it was found that cement-stabilisation of the lower half of the water level upstream side of the GCL significantly reduced deformation.