Challenges and solutions in using geosynthetic clay liners exposed to thermal desiccation risks

Abstract

Geosynthetics Clay Liners (GCLs) are widely used in geoenvironmental engineering as part of groundwater protection barrier systems. The dehydration and desiccation of bentonite in the GCLs under high temperatures, together with its suppressed self-healing when exposed to aggressive chemicals, has led to concerns about its performance and the durability of engineering barriers in these environments. In this paper, key parameters influencing chemo-thermo-hydro-mechanical behavior of GCLs under high temperature and salinity are reviewed, based on experimental evidence generated by the authors over the last four years. Next, a thermo-hydro-mechanical model is used to analyze the effects of subsoil characteristics on GCL dehydration. Finally, a new concept (I-GCLS), is proposed and experimentally investigated with the aim of preventing dehydration and desiccation cracking.