Wollongong, Australia
Wollongong, Australia

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Oliveira D.,Coffey | Arndt S.,Coffey | Cota R.,AngloGold Ashanti
ISRM Conference on Rock Mechanics for Natural Resources and Infrastructure, SBMR 2014 | Year: 2014

This paper describes a multi-scale approach used to study the Cuiaba Mine in Brazil. In such approach, a three-dimensional mine-scale or global model is used to model the mine behaviour through its entire Life of Mine. Sub-models, with finer meshes sub-models used to target specific areas. The boundaries of the sub-models are controlled by the mine-scale model to ensure compatibility of displacements and stress between the different scales. The results illustrate how such an approach is capable of representing the observed mine behaviour, including falls of ground observed during operation. In addition, it is also discussed how the results of such an approach can be used in mine planning with significant potential savings arising from the avoidance of high stress zones or zones of significant rock damage. © CBMR/ABMS and ISRM, 2014.


Patent
Ott, Moura, Stanley Inc., Stempinski, Coffey, Rup, Schirtzinger and Kironn | Date: 2015-11-11

A method is provided involving an additive manufacturing system. This method includes a step of forming a first fluid conduit (38) using the additive manufacturing system. The method also includes a step of providing a fluid coupling (32, 33, 34). The fluid coupling (32, 33, 34) includes the first fluid conduit (38) and a second fluid conduit (40). The first fluid conduit (38) is connected to and fluidly coupled with the second fluid conduit (40). The first fluid conduit (38) has a first configuration. The second fluid conduit (40) has a second configuration that is different than the first configuration.


Patent
Ott, Moura, Stanley Inc., Stempinski, Coffey, Rup, Kironn and Schirtzinger | Date: 2015-11-11

A shrouded conduit (38) is provided for arranging, for example, in a gas path (122) of a turbine engine (94). The shrouded conduit (38) includes a tubular shroud extending longitudinally along a centerline. The shrouded conduit (38) also includes a fluid conduit (40) extending longitudinally in the shroud (42). A first portion (66) of the fluid conduit (40) is connected laterally to and may be formed integral with a first portion (68) of the shroud (42).


Indraratna B.,University of Wollongong | Kianfar K.,Coffey | Rujikiatkamjorn C.,University of Wollongong | Perera D.,University of Wollongong
Australian Geomechanics Journal | Year: 2014

Application of vacuum pressure with prefabricated vertical drains in soft clays is a popular and effective ground improvement method. Application of vacuum pressure via vertical drains generates a negative excess pore water pressure (PWP) resulting in an immediate increase in effective stress. This paper summarises the recent advancements in vacuum preloading based on laboratory studies, using the conventional and modified Rowe cells. Location and the magnitude of the average PWP and degree of consolidation during vacuum preloading are investigated. Based on the laboratory experiments a new radial consolidation model is proposed for vacuum preloading incorporating non-Darcian flow.


Winter M.G.,TRL Inc | Winter M.G.,University of Portsmouth | Smith D.M.,Coffey | Eldred P.J.L.,ESG | Toll D.G.,Durham University
Geotechnical Engineering for Infrastructure and Development - Proceedings of the XVI European Conference on Soil Mechanics and Geotechnical Engineering, ECSMGE 2015 | Year: 2015

The XVI European Conference on Soil Mechanics and Geotechnical Engineering was held in Edinburgh, the capital of Scotland in September 2015. It was hosted by the British Geotechnical Association (BGA), the United Kingdom (UK) member society of the International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE). The UK has a long history of pioneering geotechnical engineering and is home to Géotechnique, the birth place of critical state soil mechanics and the venue for the prestigious Rankine Lecture. This conference and the written proceedings that this paper introduces showcased geotechnical engineering in the UK, the rest of Europe and, indeed, many other parts of the World. This paper outlines the brief history of this series of conferences and of UK Geotechnical Engineering. It also describes some key parts of the organisation of the conference and highlights some key data relating to the submission of abstracts and papers that the authors hope will be of value to organisers of future such events. © The authors and ICE Publishing: All rights reserved, 2015.


Oliveira D.A.F.,Coffey | Oliveira D.A.F.,University of Wollongong
Australian Geomechanics Journal | Year: 2014

Bertuzzi (2014) presented an update of the geotechnical design parameters previously proposed by Bertuzzi and Pells, (2002). The updated parameters focused on tunnel design with two sets of parameters introduced to cater for different design approaches dependent on the scale of the assessments. The proposed parameters provide a useful starting point and reference for practitioners working on tunnel design. However, Bertuzzi (2014) provides no guidance on the appropriate use in a model which may, in some cases, result in discrepancies between the two different design approaches and expected range of ground behaviour. This paper, provides additional comments on the differences between the two design approaches and guidance on the use of updated design parameters: The objective is a compatible behaviour independent of design approach chosen. In addition, design parameters may vary dependent on different interpretations and new sets of parameters based on the discussions in this paper are suggested as an alternative reference.


Oliveira D.A.F.,Coffey | Oliveira D.A.F.,University of Wollongong | Pells P.J.N.,Pells Consulting
Australian Geomechanics Journal | Year: 2014

The design of semi flat-roofed tunnels, i.e. with a high arch radius to roof span ratio, in Sydney has been proven successful over time. The horizontally bedded nature of Sydney's Hawkesbury Sandstone draws designers to the voussoir beam theory. Such analogy and the associated method of analysis can be easily implemented in computer spreadsheets, which significantly facilitates the design of semi flat-roofed tunnels in geological conditions such as Hawkesbury Sandstone. Like any other engineering simplified model or theory, the voussoir beam theory has some limitations. However, it seems that some of these limitations are not well understood and often ignored and/or misinterpreted. Such lack of understanding of the theory and its limitations often raises question about the applicability of the analytical solution in practice, misleading engineers to believe that the only reliable and comprehensive design method is through-numerical analysis such as Distinct Element Method (DEM). This paper investigates the applicability of the analytical or closed-form solution of the voussoir beam theory through comparison with numerical modelling, focusing on some of the perceived limitations and their impact on the design of tunnels in Sydney. The results illustrate that the voussoir beam theory can be confidently used in practice if its limitations are well understood and good engineering judgment is applied to take the local geology into account. In addition, the results also demonstrate that some of the limitations can be on the conservative side. For example, the potentially positive effect of high horizontal stresses ignored in the voussoir beam theory may explain why some of the unfavourable, conditions are less pronounced in practice.


Trainor C.R.,Charles Darwin University | Trainor C.R.,University of Vic | Trainer J.,Coffey | Knuckey C.,MWH Australia Pty Ltd
Stilt | Year: 2015

The Common Redshank Tringa totanus and Spotted Redshank T. erythropus are vagrants to Australia with most records from coastal Roebuck Bay-Broome area, southern Kimberley. Here we report the first inland Pilbara record of a redshank species, 352 km from the coast, near Newman town on 9 September 2011. The field observation was distant and the redshank could not be identified to species level. © AWSG.


Mitchell J.,Coffey | Font X.,Leeds Beckett University | Li S.,Leeds Beckett University
Anatolia | Year: 2014

The impact of mainstream tourist hotels on destination economies is clearly an important question for public policy-makers wishing to develop robust tourism policy. We adapt the methodology of value chain analysis to measure the local economic impact of a large, single tourism enterprise, to show how to generate commercially realistic data using the example of an analysis of a 1000 room all-inclusive resort in southern Turkey in partnership with TUI UK and Ireland. The data break down package revenues according to their beneficiaries and identifies areas for improvement. We further report and reflect on a 6-month evaluation of a tour operator-hotel partnership to deliver on a set of positive recommendations arising from the date to improve future impact. © 2014 © 2014 Taylor & Francis.


Badelow F.,Coffey | Poulos H.G.,Coffey
15th Asian Regional Conference on Soil Mechanics and Geotechnical Engineering, ARC 2015: New Innovations and Sustainability | Year: 2015

This paper describes the foundation design process that has been adopted for some of the world's tallest buildings, including the Burj Khalifa in Dubai and the Incheon 151 Tower in Korea. The foundation system for these super tall towers is a piled raft, founded on deep deposits of soils and rocks. The foundation systems are required to support the large building vertical and lateral loads and to restrain the horizontal displacement due to wind and seismic forces. The behavior of the foundation system due to these loads together with the foundation stiffness influences the design of the superstructure, displacement of the tower, as well as the raft foundation. Therefore, the design takes into account the interactions between soil, foundation and superstructure, so as to achieve a safe and efficient building performance. An outline will be given of the geotechnical investigations completed, the field and laboratory testing programs, and the design process. Of particular concern for the Burj Khalifa was a potential issue of cyclic degradation of skin friction. The measured and predicted building settlements will be presented. For the Incheon 151 Tower, complex ground conditions were present under the site which resulted in significant challenges for pile design and construction.

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