INFLUENCE OF SOLUTION CHARACTERISTICS ON SWELLING AND HYDRAULIC PERFORMANCE OF GEOSYNTHETIC CLAY LINERS

摘要

The influence of solutions with different valence, concentration of cation and hydrated ionic radius on swelling characteristics and hydraulic properties of geosynthetic clay liner (GCL) were explored by free swell tests and hydraulic conductivity tests. The mechanical analyses on swelling and hydraulic performance of GCL were carried out.It is found that cation valence, concentration and hydrated ionic radius all have impacts on swelling and hydraulic performance of GCL. Test results indicate that the free swell of bentonite decreases and the hydraulic conductivity of GCL gradually increases with the increase of cation valence and concentration. Monovalent cation concentration can greatly influence the swelling amount and hydraulic conductivity of the GCL, however, the influence of the concentration of divalent and trivalent cations is negligible. As the radius of the hydrated ionic increases, the free swell of bentonite in monovalent cation solutions grows, and the hydraulic conductivity of GCL gradually decreases.