2023 NSW Research Award Night
As part of their ongoing support of academic institutions and students, the Sydney and Newcastle Chapters of the Australian Geomechanics Society are offering the prestigious AGS NSW Research Award for research in Geotechnical Engineering or Engineering Geology. The award aims to provide a forum for research students from NSW universities to showcase their research to the wider Geotechnical Community.
Tailings, being mixtures of water and soil-sized particles, are waste products generated by mining and mineral extraction. Large volumes of tailings are stored on sites, often contained by embankments, forming what are known as tailings storage facilities (TSFs). TSFs fail catastrophically far too often. In many cases the tailings inside a TSF reduces in strength without the addition of significant external disturbances or loads. They may change from a soft/firm solid-like material to a lower strength, almost fluid-like, material (a phenomenon called ‘static liquefaction’) that can overload the embankment, exit the TSF through a breach and spread many kilometres, destroying lives, property and the environment. Examples of static liquefaction related TSF failures include the 2019 Brumadinho failure (Robertson, 2019; Arroyo & Gens, 2021), the 2015 Fundão failure (Sadrekarimi & Riveros, 2020) and the 1994 Merriespruit failure (Fourie et al., 2001).
Australian iron ore is mined across the Hamersley Province, Western Australia, from open pit mines composed of mineralised interlayered strong Banded Iron Formations (BIFs) and weaker shales. Mine wall failures most commonly occur in weaker shale units with low shear strengths. However, the principal controls on shale shear strength are poorly constrained. This study shows that shale geochemistry, particularly alumina content, is a good proxy for shear strength. The metasomatism that enriched iron in the BIFs has variably strengthened or weakened the interbedded shales. This study finds alumina, silica, and iron oxide (III) to be the dominant element oxides in the shales, where shales with an alumina content <10 wt% Al2O3 N are likely to be strong and those >16% wt% Al2O3 N are likely to be weak. The alumina content of the shales better correlates with shear strength than with defect surface conditions, previously thought to be the controlling factor on strength. This research permits shale shear strength to be estimated in a field environment by using a portable X-ray fluorescence analyser to determine the alumina content, helping to narrow the selection of shale samples in need of direct shear testing.
The current approach for infrastructure projects constructed above landfills is heavily reliant on adopting waste properties from literature, however landfill material is known to be heterogenous and its properties vary significantly depending on factors such as age, climate and waste type. This research is focussed on developing a practical and consistent approach utilising site investigation techniques and geotechnical laboratory testing to reasonably predict landfill settlement. The research is supported by a case study at a landfill in Sydney. The key field investigations undertaken included the collection of over 90 m of 100 mm diameter sonic drilling cores, test pitting over 5 tonnes of landfill, plate load testing, multi-channel analysis of surface waves, LIDAR and vertical seismic profiling. Laboratory tests undertaken included drained and undrained multistage triaxial tests for waste material in reconstituted and undisturbed states as well as UCS tests with small strain gauges on relatively undisturbed material from varying landfill depths.
Settlement predictions were undertaken using existing 1D settlement prediction models and PLAXIS 2D. Validation was completed over 2 years with an instrumented landfill embankment using settlement cells and extensometers. Satellite monitoring using INSAR was also undertaken and showed good correlation with the settlement cells. Back calculated field settlement corresponded well with creep from laboratory tests. Comparison of the settlement predictions using the field monitoring data and laboratory testing data exhibited a sound correlation with field monitoring data when initial settlement was corrected.
Closing date for submissions 26th June 2023
Selection of Three Finalists 12th July 2023
Finalists Presentation (Sydney) 18th October 2023
The award is open to:
- Research students
- Enrolled in any New South Wales university
- Undertaking research in Geotechnical Engineering or Engineering Geology
- Former PhD candidates already graduated within 18 months of the event date
Candidates must preferably be current research students (i.e. No PhD awarded at the time of the application) or research students that have been awarded their PhD within a year of the event. Also, they must not have applied for the AGS YGP award in the current year. However, unsuccessful candidates who have previously applied for this award and remain to be current research students are eligible to reapply for the current Research Award.
The submission for the Award shall comprise a report, with a geotechnical engineering or engineering geology theme, of no more than 3,500 words, giving a broad summary of the research. The report shall cover the research questions and rationale, the scope of the thesis, the most important results, and conclusions. The submission must be detailed enough to convey the full impact and significance of the research and should be accompanied by selected tables and figures. The student must be the sole author of the submitted report. The AGS may request supporting documentation from the candidate’s supervisor, and the supervisor’s details must be provided in the submission. The finalists will be expected to provide a written paper (with any co-authors as appropriate), which complies with the editorial requirements of the Australian Geomechanics journal (obtainable from the Australian Geomechanics Society website). The written paper must be substantially new, encompassing unpublished material, and a statement of this must accompany the written paper.
The finalists will be required to give a special presentation of their work to members of the AGS Sydney Chapter. The presentations need to be targeted at the audience – geotechnical professionals working in the industry.
The AGS will pay the reasonable out-of-town transport and accommodation costs of the finalists.
Evaluation of submissions
Written submissions will be assessed by a Review Panel. The Review Panel will select up to three finalists, who will be invited to present their submissions at AGS technical meetings in Sydney. The winner will be selected by the Review Panel at the end of their presentation on the basis of the selection criteria below. The decision of the Review Panel will be final, and no correspondence will be entered into.
The Review Panel will consist of:
- Three senior academics from NSW universities; and
- Two AGS committee members from the Sydney Chapter
- Technical content 20%
- The originality of content 15%
- Industry relevance 20%
- Clarity of written submission 10%
- Clarity of verbal communication 35%
It is expected that written papers will be prepared by the finalists for publishing in Australian Geomechanics.
The event organisers would welcome a company to sponsor the event. Expressions of interest can be made to Stefano Pirrello via [email protected]
Engineers Australia members participating in AGS technical sessions can record attendance on their personal CPD logs. Members should refer to Engineers Australia CPD policy for details on CPD types, requirements and auditing guidelines.