University of Illinois at Chicago

Department of Civil and Materials Engineering

Seminar:

October 22, 2010, Friday, 11 am – 12 pm

Room 1047 ERF

Physical response of landfill geosynthetics

Dr. Richard Brachman, P.Eng.

Associate Professor, GeoEngineering Centre at Queen’s-RMC

Queen’s University, Kingston, ON, CANADA

Contaminant release from modern landfills can be reduced to environmentally acceptable levels with a base liner system involving geosynthetic liners. A typical barrier system may consist, from the top down, of a coarse gravel layer (for leachate collection), a geosynthetic protection layer (to minimize damage to the underlying liner due to the gravel), and a geosynthetic composite liner (to minimize the escape of contaminants from the landfill) over a foundation layer. The geosynthetic composite liner involves a geomembrane (1.5-2 mm thick high-density polyethylene plastic sheet) overlying a geosynthetic clay liner (10 mm thick layer of low permeability bentonite (clay) typically encased between two geotextiles) and/or a compacted clay liner (600-1000 mm thick). Books have been written detailing the short-term response of these materials and government regulations requiring their use have been developed. The presentation will examine the physical response of these geosynthetics, with emphasis on the need to adequately asses their physical response in order to attain very long service lives (up to hundreds of years).

Dr. Brachman is an Associate Professor of Civil Engineering at Queen’s University in Canada. The phrase ‘buried but not forgotten’ captures his focus on measuring the physical response of landfill geosynthetics using innovative large-scale experiments and field studies. Dr. Brachman has made significant contributions on the assessment of long-term strains in geomembranes (GMs). He has recently completed studies on geosynthetic clay liner (GCL) hydration, dimensional stability of GCLs and field performance of exposed composite GM/GCL liners. He is a co-author of the prominent book Barrier Systems for Waste Disposal Facilities. His research on geosynthetic liners has been recognised with three Best Paper Awards in the leading journals Geotextiles and Geomembranes (2006 and 2008) and Geosynthetics International (2007).