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Frenkel M.,U.S. National Institute of Standards and Technology | Chirico R.D.,U.S. National Institute of Standards and Technology | Diky V.,U.S. National Institute of Standards and Technology | Brown P.L.,Rio Tinto Technology and Innovation | And 12 more authors.
Pure and Applied Chemistry | Year: 2011

ThermoML is an XML-based approach for storage and exchange of experimental, predicted, and critically evaluated thermophysical and thermochemical property data. Extensions to the ThermoML schema for the representation of speciation, complex equilibria, and properties of biomaterials are described. The texts of 14 data files illustrating the new extensions are provided as Supplementary Information together with the complete text of the updated ThermoML schema. © 2011 IUPAC. Source

Preece D.S.,Orica United States Inc. | Yang R.,Orica United States Inc. | Pilz J.,Rio Tinto Technology and Innovation | Zavodni Z.M.,Rio Tinto Technology and Innovation
Rock Fragmentation by Blasting - Proceedings of the 9th International Symposium on Rock Fragmentation by Blasting, FRAGBLAST 9 | Year: 2010

An overland conveyor was constructed at a surface coalmine to reduce the truck haul distance and make the operation more efficient. An important element in this system is a truck dump facility to transfer coal from truck to conveyor. The coal is dumped from above and processed through a crusher before loading onto the conveyor that carries it to the coal processing facility. The configuration of the mechanically stabilized earth (MSE) retaining wall is typical of many mining operations and utilizes a series of MSE walls surrounding a crusher to create a "pocket". The Owner requested that the potential for blast vibration damage to the wall be assessed and criteria developed to reduce the potential for blast induced damage. This paper presents the methodology used to assess such blast effects, a comparison to measured values and demonstrates the conservatism inherent in simplistic earthquake based analysis. © 2010 Taylor & Francis Group. Source

Duffy G.,Rio Tinto Technology and Innovation | Duffy G.,Griffith University | Mills P.,Rio Tinto Technology and Innovation | Mills P.,Griffith University | And 2 more authors.
2015 10th Asian Control Conference: Emerging Control Techniques for a Sustainable World, ASCC 2015 | Year: 2015

The effective performance of various processing plants is reliant on many contributing factors. Such factors include equipment availability and operating performance, operating practices, technical influence and the ability to control the process in a consistent and high performing manner. Operating objectives need to be established to allow for product quality and throughput targets to be achieved throughout. This paper elaborates on an assessment of various categories of plants to demonstrate the wide dominance of the theme and aims to assess the performance of specific industrial plants, namely, Coal Handling Preparation Plants and Bauxite Beneficiation Plants against these parameters. The assessment will focus on the process as well as the control schemes supporting these process objectives. © 2015 IEEE. Source

Fernandez F.,Rio Tinto Technology and Innovation | Watt G.,Rio Tinto Technology and Innovation | Ooi J.,Rio Tinto Technology and Innovation
Australian Journal of Civil Engineering | Year: 2012

The paper elaborates on a methodology of damage assessment based on conditions encountered in the Argyle Diamonds Underground Project (ADUP). It has been developed iteratively over a number of months and has been used to comprehensively represent damage conditions as the undercut front advances. Correlation between damage and convergence has been established. The ground support regime that has been implemented at ADUP to withstand very severe squeezing (Hoek & Marinos, 2000) has produced the outcome that only in limited areas of extreme squeezing (in excess of 20% convergence) has stripping and rehabilitation been required to enable undercutting operations to continue. This issue highlights the importance of the implementation of adequate guidelines to maintain drive stability and safety during undercutting. The long-term and strategic implications of correlating damage conditions with convergence and therefore deformation are that a practical predictive model can be developed. This can then be used to forecast the level of damage that is likely to occur in the undercut drives and extraction level drives based on displacement modelling. This model allows an optimised level of support and reinforcement to be designed depending on the predicted damage conditions. Such a "predictive" model could be used to estimate the optimal level of support and reinforcing (and to establish a realistic budget and schedule for the work), as well as an ongoing tool for forecasting damage conditions (and remedial support and reinforcing) during undercutting and block caving progression. © 2012 Institution of Engineers Australia. Source

Wuestefeld A.,University of Bristol | Kendall J.M.,University of Bristol | Verdon J.P.,University of Bristol | Van As A.,Rio Tinto Technology and Innovation
Geophysical Journal International | Year: 2011

Changing stress conditions are well known to cause rupturing of rock. This is well constrained on a small scale from laboratory experiments and inferred on a much larger scale from tectonic earthquakes. Here, we present a study of rock fracturing induced by changes in stress state during block-caving operations in an Australian mine. This intermediate-scale study provides further evidence of the scalability of processes involved in rock fracturing and thus helps to link laboratory and seismological observations. We analyse the temporal evolution of rock fracturing during a production cycle using the analysis of fracture-induced anisotropy. Fracturing of the rock mass is monitored using evidence of seismic anisotropy from estimates of shear wave splitting and their subsequent inversion for fracture parameters. The data set consists of more than 40000 three-component seismograms recorded by an array of sensors, which provides excellent ray coverage. We applied a novel automatic quality assessment technique to handle this large data set and find that anisotropy, and thus fracturing, correlates strongly with the excavation process. We then perform a grid search over a series of synthetic models based on rock physics to invert the splitting parameters for fracture orientation and density. Finally, by applying a sliding window on our results, we are able to identify production related fracture evolution. During production the fracture density increases, with horizontal fracture density being stronger than the vertical fracture density. This can be explained by the removal of the supporting rock during caving. During short intervals of reduced production, the horizontal fracture density decreases, whereas vertical fracture density increases. We relate this to change in stress regime with reducing overburden mass during cavity collapse. This scenario is similar to a collapsing caldera or the inverse of an inflating magma chamber. © 2011 The Authors Geophysical Journal International © 2011 RAS. Source

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