R.M. Hardy Address by Dr. Murray Fredlund
Movement Towards 3D Stability Analysis and Digital Twins
Monday October 2nd
Dr. Murray Fredlund
Murray Fredlund completed B.E.and Ph.D. degrees in Civil Engineering at the University of Saskatchewan. He was the founder of SoilVision Systems Ltd., which was acquired by Bentley Systems Inc. in 2018. He has spent much of his time over the past 24 years guiding the development of geotechnical software development and being involved in slope stability consulting projects. His work continues in providing strategic advice to guide software development at Bentley.
Since the first analysis of a slope failure in Goteborg harbour in 1915 the geotechnical profession has been utilizing numerical analysis to determine the stability of earth slopes. The 1950s to 1980s witnessed the refinement of 2D methods associated with the limit equilibrium method (LEM) of analysis. The use of strength reduction techniques along with finite element analysis (FEM) was introduced in the early 1980s and has been gaining support in the industry. 1990s to 2010s saw the introduction of 3D analysis techniques in both FEM and LEM methodologies. Geotechnical engineers have relied heavily on software in order to analyze embankment dams and tailings storage facilities (TSFs) due to the complex nature of the physics of a slope failure. 2D analysis methods are a common method of estimating the performance of proposed designs but are they adequate?
In spite of improvements in the software packages available for stability analysis, the rate of failure of TSF failure has remained relatively constant from 1965 to the present. It is intuitively expected that with advancements in our ability to analyze geotechnical structures our ability as geotechnical engineers to design structures which endure the test of time would improve.
What has happened in practice is that our ability to BUILD advanced geotechnical structures has outpaced our ability to ANALYZE the performance of these construction and engineering marvels. This issue is particularly troublesome given the significant pressure to build larger and more complex geotechnical structures with decreasing budgets. This dynamic can be seen demonstrated especially in the mining market area where the pressure to dig deeper or build higher is enormous in order to supply the modern appetite for minerals. This presentation examines the use of 3D methodologies and digital twin technologies in slope stability analysis as a method to improve our collective ability to estimate the long-term performance of earth dams and TSFs.
IGS-NA Keynote by Dr. Jorge G. Zornberg
The Quest for Properties Governing the Geosynthetic Stabilization of Roadway Bases
Monday October 2nd
Jorge G. Zornberg, Ph.D., P.E., F. ASCE
Professor and Joe J. King Chair in Engineering,
The University of Texas at Austin
Past-President, International Geosynthetics Society
Prof. Zornberg has over 35 years of experience in practice and research in geotechnical and geosynthetics engineering. His research focuses on transportation geotechnics, geosynthetics, unsaturated soils, expansive clays, and environmental geotechnics. He served as president of the International Geosynthetics Society (IGS). He has authored over 500 technical publications, written several book chapters, and been awarded three patents. Prof. Zornberg received numerous prestigious awards, including the Presidential Early Career Award for Scientists and Engineers (PECASE), awarded by the President of the United States. The IGS recently established the “Zornberg Lecture,” an honorary lecture recognizing his contributions to the geosynthetics discipline.
Lateral restraint is the governing mechanism associated with stabilizing unbound aggregate layers in pavements. Reproducing this mechanism in the laboratory may be challenging because, while the original loading source is cyclic (traffic), lateral restraint develops through interlocking and interfacial friction between the geosynthetic and the aggregate to restrain the development of permanent lateral strains. Considering lateral restraint’s relevance in quantifying the benefits of geosynthetics embedded within (or adjacent to) unbound aggregate layers, this presentation focuses on two experimental approaches to quantify this mechanism.
The first experimental approach aims at defining a design parameter, identified as the Stiffness of the Soil-geosynthetic Composite (KSGC), which is obtained from Soil-Geosynthetic interaction (SGI) tests and is practical for use in specifications and design. The second experimental approach that quantifies the lateral restraint mechanism involves one-third scale accelerated pavement tests performed on pavement test sections stabilized with various geosynthetics. The performance of these sections was compared to that in the non-stabilized (control) section to evaluate the Traffic Benefit Ratio (TBR) at failure rut depth for each geosynthetic. The TBR obtained showed a strong linear correlation to the KSGC of the corresponding geosynthetic determined by SGI tests. Overall, the KSGC parameter was found to represent a suitable indicator of the performance of pavements with unbound aggregate layers stabilized using geosynthetics.
IAH-CNC Keynote by Dr. Stephanie Wright
Past and Future Directions of Cold Regions Hydrogeology in a Warming World
Tuesday October 3rd
Dr. Stephanie Wright, Ph.D.,
Dr. Wright is an Assistant Professor in the Department of Civil Engineering at Queen’s University with a background in environmental and geological engineering. Her expertise is in fractured rock hydrogeology, cryo-hydrogeology, and environmental/isotope tracers. She works closely with First Nations and Indigenous communities to study the impacts of climate change on groundwater resources in cold regions across Canada. She was an NSERC Postdoctoral Fellow at Wilfrid Laurier University and is an Associate Editor for Hydrogeology Journal.
Climate warming is driving unprecedented changes to cold regions globally. In seasonally frozen environments, warming winters are altering the patterns of infiltration and recharge, placing uncertainties on already vulnerable groundwater supplies. In the Circumpolar North, rapid warming is leading to permafrost thaw that is activating groundwater systems, offering opportunities for new drinking water resources, while increasing the risk of contaminant mobilization and impacts to critical infrastructure. To collectively manage and protect groundwater resources, it is imperative to develop community-partnered research that leverages bilateral knowledge exchange and focuses on the needs and priorities of those most affected by climate change.
CGS Colloquium 2023 by Dr. Pooneh Maghoul
Role of Geotechnical Engineering in Human Settlement on the Moon and Beyond: Challenges and Opportunities
Tuesday October 3rd
Dr. Pooneh Maghoul, Ph.D., P.Eng.
Dr. Pooneh Maghoul is an Associate Professor of Geotechnical Engineering and the Director of the Sustainable Infrastructure and Geomechanical Research Laboratory at Polytechnique Montréal. She is also VP Finance of the Canadian Geotechnical Society (CGS), a Director at the Mars Society of Canada, and co-Chair of the Geotechnical Engineering and Foundation group of the American Society of Civil Engineers (ASCE) Lunar Engineering Design, Analysis, and Construction. Dr. Maghoul’s research interests focus primarily on sustainable development of infrastructure which is resilient to climate change and harsh environments in Space. This includes permafrost engineering, smart mining, energy transition, low carbon materials for ground improvement, geo-structural health monitoring, and In-Situ Resource Utilization (ISRU) on the Moon and beyond. She is a recipient of several international and national awards such as the Outstanding Young Geotechnical Engineer award of the International Society for Soil Mechanics and Geotechnical Engineering. Her research has resulted in + 13 patents and software licenses and the creation of several startup companies.
The Moon has become a renewed focus of interest for exploration in recent years, with multiple space agencies and private companies planning lunar exploration activities. Canada has joined humanity’s return to the Moon, through the Lunar Exploration Accelerator Program (LEAP) of the Canadian Space Agency (CSA). The main goals of the 2025 lunar landing are to achieve sustainable exploration by 2028 via collaboration with commercial and international partners, construct a sustainable, long-term human base camp, and lay the foundation for eventual crewed trips to the ultimate human-spaceflight destination, Mars, sometime in the 2030s.
The success of every ground-based construction project, whether on Earth or on the Moon, strongly depends on the robust foundation design and the capacity of foundation soils to withstand external loads in the short-, mid-, and long terms. Considering uncertainties and unknown unknowns in an unknown world in the geotechnical design of lunar infrastructure is of paramount importance. Hazards are inevitable, however building substantial infrastructure without understanding the physical and mechanical properties of lunar regolith can result in structural failure due to soil failure.
In this presentation, Dr. Maghoul will discuss the strategic importance of Canada’s presence on the Moon. The state-of-the-art technologies and their limitations in the lunar conditions will be presented. Then, the ongoing research activities in Dr. Maghoul’s research lab regarding lunar geotechnics and known-unknowns, geophysics, space mining and automated prospecting of water-ice, and instrument development will be presented.
Heritage Luncheon by Delwyn G. Fredlund
Journey into Unsaturated Soil Mechanics
The Heritage Talk summarizes the progress made in understanding and applying Unsaturated Soil Mechanics as witnessed over the lifetime of research by Del Fredlund.
Delwyn G. Fredlund has spent over 40 years conducting research into the behavior of unsaturated soils. Most of his career was spent at the University of Saskatchewan, Saskatoon, where he organized the Unsaturated Soils Group for the study of all areas of unsaturated soil behavior. Del Fredlund obtained his B.Sc. degree from the University of Saskatchewan, Saskatoon in 1962. In 1966 Del Fredlund joined the Department of Civil Engineering at the University of Saskatchewan, Canada. In 1973 he obtained his Ph.D. from the University of Alberta. Dr. Fredlund’s research studies have resulted in the authorship of two books, namely, “Soil Mechanics for Unsaturated Soils”, and “Unsaturated Soil Mechanics in Engineering Practice” published by John Wiley & Sons. Dr. Fredlund published approximately 500 journal and conference research papers and has delivered many keynote lectures at conferences. He has been the recipient of numerous awards