Influence of Prehydration Without Load on The Hydraulic Performance of Geosynthetic Clay Liners

Geosynthetic clay liners (GCLs) are used in a variety of geoenvironmental applications to ensure lining. In order to properly function GCLs have to be confined and hydrated. It is usually recommended that load be applied on top of the GCL immediately after installation. The question that arises is related with the potential impact of the hydration without load on the final hydraulic performance of the GCL as compared to a situation where it would have been hydrated under load. The paper will thus describe the impact of various hydration modes of a GCL. Flow rates measurements were performed for virgin GCL samples and following the different modes of hydration. 5 different GCL coming from different manufacturers were used. The best performance was obtained with needle punched GCLs but the influence of prehydration without load was only significant for one of the two stitched GCLs tested.