Improvement on the Performance of Geosynthetic Clay Liners Using Polymer Modified Bentonite

Abstract

Polymers have been added to improve bentonite swelling capacity with the view of improving the hydraulic performance of GCLs. This paper presents an on-going study in which three bentonites were polymer-treated (0.5%, 1%, 2% by weight) and polymerincluded changes to swell index and Atterberg limits were determined. The liquid limit values generally increased with polymer content, although a decrease appeared at higher concentration of some polymers. However, polymer addition had only slight effects on plastic limits. Higher polymer concentration, regardless of type, generally resulted in higher swell index values and swell percentages. Different response of bentonites to polymers occurred which is mainly due to the individual characteristics of bentonites, such as chemical composition, type of gel formation etc.