If you havn’t already done so, please take the time to register for the CCLT next week.  Registration deadline is extended until 3pm on Friday April 25.  Please note the luncheon will be served starting at 12:00, so please arrive no later than 11:45 to the registration desk. 

 

Visit our website: www.cgygeosociety.org for more event information.

 

CALGARY GEOTECHNICAL SOCIETY

2007/2008 LECTURE SERIES

 

Date:                Wednesday April 30, 2008

 

Place:               Austrian Canadian Cultural Centre, 3112 - 11 Street NE, Calgary

 

Time:                12:00 pm - Buffet Lunch

                        12:15 to 1:15 pm – Lecture

 

Cost:                $20 per person

                        $10 full-time students

                         (pay at the door by cash or cheque only, pre-registration is required)

 

RSVP:              By email (CCLT@cgygeosociety.org) by Friday April 25 at 3pm.

                        Please include your company name, phone number and indicate any dietary restrictions.

 

Speaker:           Dr. Michel Aubertin, Ph.D., M.Sc.A., B.Eng.

                        Professor, École Polytechnique de Montréal

 

Topic:               The use of laboratory and field techniques with unsaturated flow modelling to assess coarse grained material behaviour: Application to waste rock piles

 

CCLT Sponsors:            The Canadian Foundation for Geotechnique, AMEC Earth & Environmental, EBA Engineering Consultants, Jacques Whitford, J.D. Mollard and Associates, and the Canadian Geotechnical Society (organizers).

 

 

Abstract:

Mining activities produce large volumes of waste rock, which are typically deposited in piles on the soil surface, above the water table. Such piles can cover areas of several tens of hectares and can reach over a hundred meters in height.

 

For hard rock mines, the waste rock grain size can vary from silty particles to metre-scale blocks. The internal structure of a pile constructed on a relatively flat surface typically includes two main zones. The first zone corresponds to the heart of the pile, and is formed by several sub-horizontal stratifications (with dense and loose layers) due to the heavy mine equipment traffic which induces local compaction and degradation of the waste rock. The second zone corresponds to regions where waste rocks are deposited by push-dumping or end-dumping close to the external flank of the pile, inducing grain size segregation along the slope. Depending on the deposition sequence, grain size distribution and bench height, a gradation may then be observed, with coarser particles (with cobbles and blocks) near the base and finer particles (silty sand and gravel) near the crest, together with inclined stratifications. These internal features affect the distribution and flow of water (and air) in the pile.

 

To assess the internal distribution of materials within the pile, a combination of several tools is usually required which can provide information on the hydrogeological and geochemical characteristics of the waste rock. In this regard, geophysical tools (particularly EM & GPR) are very interesting because they can lead to a three-dimensional mapping of property variations. The information gathered from a combination of appropriately selected techniques can be used to construct numerical models to further study unsaturated water flow and reactive transport. Such simulations help better understand the pile response in its actual and future states, which in turn provides input to adjust the deposition sequence, to plan for closure, and to select an in situ groundwater monitoring strategy.

 

The presentation will give an overview of techniques that have been developed to characterise material properties in the laboratory and in the field, and to obtain a general picture of a pile’s internal structure.  Additional results on unsaturated reactive transport modelling, obtained by the lecturer and collaborators, will also be shown to illustrate how the internal pile structure may influence its hydro-geochemical and environmental response.

 

About the Speaker:

After a few years with a consulting firm and more than 5 years at the Université du Québec in Abitibi-Témiscamingue (UQAT), Michel Aubertin joined École Polytechnique as Assistant Professor in 1989. He became Associate Professor in 1992 and a full Professor in 1996. From 1994 to 1999, he was in charge of the undergraduate program in mining engineering, a bilingual cooperative program jointly run with McGill University.  In June 2001, he was appointed to the Industrial NSERC Polytechnique-UQAT Chair in Environment and Mine Wastes Management. This Chair involves the participation of two universities (École Polytechnique and UQAT), as well as mining companies, specialized consulting firms and government agencies. The mandate of the Chair was renewed in June 2006 for five years.

 

Professor Aubertin’s teaching and research activities are focused on mining geotechnics and hydrogeology. Over the years, he has directed or co-directed more than 45 graduate students, including 14 PhD students and 6 post-doctoral fellows.  He was director of the rock mechanics division of the Canadian Geotechnical Society (CGS), going on to become one of the Society’s two vice-presidents (1997-1998). He co-edited the proceedings of the 1st Canadian Conference on Environmental Geotechnics (1991), and was President and Editor of the 2nd North American Rock Mechanics Symposium (NARMS ’96). He was Associate Editor of the Canadian Geotechnical Journal (1999–2004), and was on the editorial board of the Pergamon-Elsevier International Journal of Plasticity (1994–2002). He continues to be involved in the organization of a variety of congresses, seminars, and national and international conferences, and regularly acts as a reviewer for scientific committees, technical journals, and funding agencies such as the NSERC Civil Engineering Grant Selection Committee (GSC 06, member in 2001-2002 and Chair in 2003) and E.W.R. Steacie Grants (member 2006). He chaired the Canadian Geotechnical Research Board from 2003 to 2008.  He is now President-Elect of the Canadian Geotechnical Society.

 

M. Aubertin is a member of various professional associations, including the Ordre des ingénieurs du Québec, CGS, ASCE, CIM, CSCE, SME-AIME, and IAH. He has been awarded a number of prizes for his teaching and research activities.  These include Fellow of the Canadian Society for Civil Engineers (1999), the J.A. Franklin and T. Stermac prizes from the Canadian Geotechnical Society (1999), the R&D Award of Excellence from NAGS  (North American Geosynthetics Society, 1999), the ASCE Journal of Environmental Engineering Editor’s Award (2001), the Mérite géoscientifique du Québec (2001), and the Réseau Environnement Arnold Drapeau award (2001). In 2003, Professor Aubertin was named Fellow by the Canadian Academy of Engineering (FCAE) and the Engineering Institute of Canada (FEIC). In 2005, he received the John B. Sterling medal from the EIC for his leadership and professional contributions.  He was invited to give the Cross Canada Lecture Tour of CGS in the Spring of 2008.