Complex Systems in Slope Engineering
Tim Sullivan
All slope design relies heavily on scientific theory and practice. Much of this is strongly influenced by the expertise and experience of the individual practitioner and in part there are also specific generic and or company specific approaches. More recently specific guidelines have been developed to link mining geomechanics research with best practice. The aim being to provide practitioners with the tools to try and ensure that slopes are stable and if not, the expected economic returns are achieved without economic losses, injury or death. These approaches and the guidelines are generally focussed on the immediate slopes themselves. However, many sites are large or particularly complex, they can span many different geographic and geological settings, entail many different engineering structures, and importantly often encroach on other natural infrastructure. In this situation the slope may no longer be isolated, decoupled from its surrounds. The total design problem then becomes not the stability of the slope itself, but how slope could interact with the natural and man-made infrastructure to form a complex system. A characteristic feature of complex systems is that they are self-organising, with potentially adverse interactions and emergent outcomes. In complex systems the clues are often subtle, the interactions of the technical components can be very difficult to predict, they can develop over a long period and then only manifest themselves as small changes before a much larger adverse event occurs. Then the design, slope management, understanding and monitoring systems, focussed on the slope, are insufficient to preclude adverse outcomes. This is an empirical paper based on the author’s 50 years of experience with investigation and design in small and large complex systems. The focus is on understanding and awareness of this rather unique sub-set of slope design problems.
Tim Sullivan Director, PSM (Pells Sullivan Meynink)
Mr. Sullivan graduated from Macquarie University in 1973 with a degree majoring in geology. He joined Coffey’s in 1974 and was employed with them till 1993. While at Coffey’s Mr Sullivan was a Director of the firm and established the Mining Geotechnics Group. In 1979-80 Mr Sullivan undertook postgraduate studies in London and was awarded an MSc from the University of London and a DIC from the Imperial College of Science and Technology. From 1992-1993, he was a Visiting Professor at the School of Mines, UNSW. From 2002 to 2007 Mr Sullivan was Adjunct Professor of Geotechnical Engineering, UNSW. From 1997 to 2000 Mr Sullivan was also the NSW Coroner’s adviser on the Thredbo Landslide. In 1993 Mr Sullivan established his own firm Pells Sullivan Meynink. Mr Sullivan has been a geotechnical consultant for some of the world’s largest mining operations and companies; including BHP Billiton, Rio Tinto, Xstrata, Glencore, Newmont, Anglo Gold, Pilbara Iron and Newcrest. In addition to all the states and mainland territories of Australia, major projects have been located in India, Papua New Guinea, Indonesia, Thailand, Laos, Africa, South America, Chile, Philippines, Mexico, New Zealand and Fiji. Mr Sullivan has worked on over 400 mining projects at all stages from planning to operating.
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