+publisher:"University of Adelaide" +contributor:("School of Civil, Environmental and Mining Engineering")

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University of Adelaide

1. Arjomand, Elaheh. Cement Sheath Integrity Assessment Subject to Pressure and Temperature Variations.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/120307

► The exploration and exploitation of hydrocarbon wells should not cause any environmental hazards including contamination of groundwater (aquifers) and atmosphere. The cement placed in the… (more)

▼ The exploration and exploitation of hydrocarbon wells should not cause any environmental hazards including contamination of groundwater (aquifers) and atmosphere. The cement placed in the annular gaps between the casing strings and the formation acts as a key barrier to provide zonal isolation and maintain the integrity of the wells. The integrity of the cement sheath and the cement sheath interfaces is susceptible to be compromised during well operational processes, including but not limited to, pressure integrity tests (PIT), completion operations, stimulation treatments, and production processes. The cement sheath may experience different types of mechanical damage as a result of being exposed to these different wellbore operational procedures. Therefore, understanding of cement failure mechanisms is of the utmost importance for better assessments of wellbore integrity. This thesis demonstrates the results of the experimental-numerical studies and investigates the integrity of the cement sheaths subjected to pressure and temperature variations. The overall purpose of this study is to improve the modelling capabilities of cement sheath integrity assessments by employing a more comprehensive constitutive model for the cement sheath compared to the rest of the models previously used. The experimental studies on the behaviour of the cement-based specimens under compression tests showed a strong non-linearity in the obtained stress-strain curves which confirms the necessity of applying plasticity theories. However, it is hard to explain the elastic stiffness degradation of the cement-based materials which happens during experiments using the classical plasticity theories. Therefore, in this thesis, the modified Concrete Damage Plasticity (CDP) model was employed, particularly formulated for modelling geo-materials such as rocks, concrete, and cementitious materials. The Concrete Damage Plasticity is a continuum model which combines plasticity and damage mechanisms, considering two different tensile and compressive state of damage. The yield criterion in the CDP model also represents the pressure-dependency of the geo-material behaviour under shearing at different levels of confinement in addition to the incorporation of non-associated flow rule (material dilatancy). These features show the superiority of the CDP model for employing in cement sheath integrity assessments. However, the paucity of cement class G mechanical parameters, e.g. lack of experimental data under different confining pressure and tensile properties, was an impediment to the incorporation of Concrete Damage Plasticity model. Therefore, the experimental aspect of this study intends to expand the cement class G inventory. The experimental data and analyses added to inventory are as followed. The investigations of curing temperature and pressure confinements effects on the strength and post-peak response of the cement class G under compression and also obtaining cement tensile properties. The experimental results show by increasing the curing… Advisors/Committee Members: School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Cement sheath integrity; concrete damage plasticity model; compression damage; tensile damage

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APA (6^th Edition):

Arjomand, E. (2018). Cement Sheath Integrity Assessment Subject to Pressure and Temperature Variations. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/120307

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Arjomand, Elaheh. “Cement Sheath Integrity Assessment Subject to Pressure and Temperature Variations.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/120307.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Arjomand, Elaheh. “Cement Sheath Integrity Assessment Subject to Pressure and Temperature Variations.” 2018. Web. 19 Feb 2020.

Vancouver:

Arjomand E. Cement Sheath Integrity Assessment Subject to Pressure and Temperature Variations. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/120307.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Arjomand E. Cement Sheath Integrity Assessment Subject to Pressure and Temperature Variations. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/120307

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Nicholas, Grant Deon. An integrated risk evaluation model for mineral deposits.

Degree: 2014, University of Adelaide

URL: http://hdl.handle.net/2440/86234

► The core asset of most mining companies is its mineral resources and reserves. The company produces ore from its reserves, which is a subset of… (more)

▼ The core asset of most mining companies is its mineral resources and reserves. The company produces ore from its reserves, which is a subset of its mineral resources associated with varying levels of geoscientific confidence and uncertainty. One of the key evaluation challenges is to distil technical complexity into a financial model that is usually designed to focus only on one or two key valuation indicators, such as net present value (NPV) or internal rate of return (IRR). The driver behind this research was whether conventional evaluation techniques for mineral projects can evaluate accurately both the spatial and temporal characteristics of project risks in financial terms, due to their inherent nature to understate the true variance, and under-value or over-value the actual NPV. How can conventional evaluation methods be compared to an innovative, integrated evaluation technique that quantifies the non-linear impacts of spatial resource variables on production constraints in financial terms, measured at the appropriate temporal scale? To answer these questions, this research focused on developing an innovative risk evaluation methodology for two different diamond deposits and one gold deposit to incorporate spatial, non-spatial and financial data across the evaluation pipeline. The author developed an integrated evaluation modelling (IEM) framework based on a unique bottom-up methodology that follows every estimation block through the mining and processing value chain, i.e., it accurately captures the spatial variability of all relevant value chain variables in the ground and their correlated impacts on production constraints such as grade, density and processing characteristics. This variability is propagated through the processing value chain at a mining block (or selective mining unit, “SMU”) scale. The IEM approach revealed differences in NPV between a ‘bottom-up’ (or Local) evaluation method and a ‘top-down’ (or Global) evaluation method – see Figure 1. While the actual NPV for the virtual ore body (VBod) was CAD 2.1 million, the figure shows that the local evaluation method (bottom-up) more closely approximated the actual NPV of the project than the global (top-down) evaluation method, which materially over-estimated the NPV. The author demonstrated that cash flow constituents derived from annual estimates in a top-down approach will not correctly reflect the asymmetries due to operational variability on a local, daily basis. The ‘bottom-up’ evaluation method represented a more accurate way of deriving annual cash flow estimates needed to make decisions on projects by accumulating the appropriate values from a bottom-up approach, i.e. daily, monthly, quarterly then derive annual estimates for NPV forecasts. The two main advantages of the IEM methodology are that firstly, it accurately reproduces the spatial resource characteristics of blocks at the appropriate temporal scale; and secondly, direct linkages are created between the resource–reserve–financial models within a single software environment.… Advisors/Committee Members: Dowd, Peter Alan (advisor), Jaksa, Mark Brian (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: integrated evaluation model; mineral deposits; risk evaluation; geostatistics; real options

…Submitted by Grant Nicholas to the University of Adelaide as a thesis for the degree of Doctor of… …university or other tertiary institution without the prior approval of the University of Adelaide… …University of Adelaide who all, at different times, assisted me with funding and support for my… …times. I owe a debt of gratitude to Prof. Peter Dowd and Dr. Mark Jaksa at the University of… …Adelaide as my supervisor and co-supervisor, respectively, and for making time in their busy…

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APA (6^th Edition):

Nicholas, G. D. (2014). An integrated risk evaluation model for mineral deposits. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/86234

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Nicholas, Grant Deon. “An integrated risk evaluation model for mineral deposits.” 2014. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/86234.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Nicholas, Grant Deon. “An integrated risk evaluation model for mineral deposits.” 2014. Web. 19 Feb 2020.

Vancouver:

Nicholas GD. An integrated risk evaluation model for mineral deposits. [Internet] [Thesis]. University of Adelaide; 2014. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/86234.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Nicholas GD. An integrated risk evaluation model for mineral deposits. [Thesis]. University of Adelaide; 2014. Available from: http://hdl.handle.net/2440/86234

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

3. Zhang, Tao. A generic mechanics approach for predicting shear strength of reinforced concrete beams.

Degree: 2014, University of Adelaide

URL: http://hdl.handle.net/2440/89099

► This thesis includes a series of journal articles in which a mechanics based segmental approach is developed for simulating shear behaviour of reinforced concrete (RC)… (more)

▼ This thesis includes a series of journal articles in which a mechanics based segmental approach is developed for simulating shear behaviour of reinforced concrete (RC) beams. Using the well-established theories of partial interaction and shear friction, the generic mechanics approach simulates the formation and widening of diagonal cracks and shear sliding failure for RC beams. Being mechanics based, the proposed approach can be generally applied to various kinds of structures, that is any cross section, with any type of concrete and reinforcement and with any bond properties. Moreover, no component of the proposed approach relies on empiricism to account for the mechanics of shear failure, and the approach can accommodate any material characteristics which with time can be refined and revisited to improve the accuracy of shear strength simulation. In developing the mechanics of the segmental approach for prestressed RC beams, it is shown how the approach is applied to analyse shear behaviour and simulate shear failure of prestressed beams. Parametric studies are conducted to explain the effect of prestress on shear behaviour. For verification, the proposed approach is applied to 102 specimens and the analytical and experimental results are in good agreement. The generic nature of the mechanics approach is shown by its application to steel and fibre-reinforced polymer (FRP) reinforced beams and one-way slabs without stirrups. From the mechanics of the segmental approach, closed form solutions are derived for shear design and validated by comparisons with test results and code predictions of 626 steel and 209 FRP reinforced specimens. Having developed closed form solutions for beams without stirrup, the approach is extended to incorporate shear reinforcement. Significantly, the partial interaction analyses of longitudinal and transverse reinforcements are directly linked. Furthermore, simple solutions are derived through mechanics for tension stiffening and can be applied for shear and flexure analysis in the segmental approach. The numerical and closed form solutions are applied to 194 specimens and validated with good correlation of predicted and measured results. The generic mechanics approach is further extended to accommodate the effect of axial load on shear strength. The proposed approaches are applied to 61 specimens and simulation results show good agreement with test data. A series of push-off tests are conducted to investigate the shear friction parameters for initially uncracked concrete under low levels of confinement. In addition, it is shown that the concrete shear friction properties can be extracted from simple confined cylinder tests and then applied in the segmental approach to predict shear sliding capacity. Thus this research highlights the potential to reduce the significant cost of empiricisms in terms of time and money when developing innovative RC products and generic design guidelines. The broad application of the mechanics based segmental approach presents a general solution to… Advisors/Committee Members: Oehlers, Deric John (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: shear strength; reinforced concrete; mechanics approach; beam

…x28;CSC) and the University of Adelaide (UoA) are greatly appreciated…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhang, T. (2014). A generic mechanics approach for predicting shear strength of reinforced concrete beams. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/89099

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Tao. “A generic mechanics approach for predicting shear strength of reinforced concrete beams.” 2014. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/89099.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Tao. “A generic mechanics approach for predicting shear strength of reinforced concrete beams.” 2014. Web. 19 Feb 2020.

Vancouver:

Zhang T. A generic mechanics approach for predicting shear strength of reinforced concrete beams. [Internet] [Thesis]. University of Adelaide; 2014. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/89099.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang T. A generic mechanics approach for predicting shear strength of reinforced concrete beams. [Thesis]. University of Adelaide; 2014. Available from: http://hdl.handle.net/2440/89099

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

4. Liu, Yang. Discrete Element Modelling of Geocell-Reinforced Railway Ballast and Experimental Examination of Geocell Failure Mechanisms.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/117672

► Rail transport is one of the major means of conveyance of passengers and goods worldwide. Due to the cyclic impact of trains, breakage and rearrangement… (more)

▼ Rail transport is one of the major means of conveyance of passengers and goods worldwide. Due to the cyclic impact of trains, breakage and rearrangement occurs to the ballast in the trackbed of a railway. As a result, the trackbed is prone to lateral creep and subsidence, which is deemed to undermine the serviceability of rail tracks, and likely cause catastrophic failure of the tracks. To gauge the serviceability of the tracks, a significant amount of expense is spent annually to maintain the serviceability of rail tracks. To minimise this expense, a variety of engineered methods have been suggested and attempted to reinforce the ballast of the trackbed, such as embedment of geosynthetics into the ballast layer. Of these geosynthetics solution, geocells are an emerging and promising option of reinforcing railway ballast. However, to date, the study of geocell-reinforced railway is much limited, possibly due to the high-cost involved in an experimental or field-testing program, and the difficulties of modeling railway ballast with the currently available simulation technics. To gain an insight of the geocell reinforcement, numerical studies have been carried out to examine the mechanical responses of geocell-reinforced railway ballast. This research adopts a commercially available Discrete Element Method (DEM) software package, Particle Flow Code (PFC) 3D to simulate the interaction between the geocell and the discrete particles of ballast. Both monotonic and cyclic loading environments are assessed, and ballast breakage is considered. Displacements and stresses at both micro- and macro-scales are assessed for control and reinforced scenarios. This study demonstrates that the geocell can effectively reduce settlement and ballast breakage. The geocell stiffens its embedded layer and reduces stress propagation into the underlying layer. The outcomes of this study seek to encourage likely reduction in trackbed thickness and width, to save construction cost and improve the sustainability of the railway trackbed. Furthermore, the presented study experimentally examines the responses of geocell junctions and cell-walls under various loading conditions. An extensive testing program has been undertaken to assess the geocell junctions and geocell walls. A ductility ratio is developed to measure the rapidness of failure under different short-term loading scenarios for both the cell-wall and junction. The observed failure patterns are presented and an evaluation of the implications of the practical uses of geocells is drawn. Advisors/Committee Members: Deng, An (advisor), Jaksa, Mark (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: DEM; geocell; ballast; geosynthetics; railway

…laboratories of the School of Civil, Environmental and Mining Engineering for providing guidance and… …111 Figure 4.6. University of Adelaide Instron machine… …prior approval of the University of Adelaide and where applicable, any partner institution… …institution without the prior approval of the University of Adelaide and where applicable, any… …kind assistance given by the administrative staff at the University of Adelaide. I would…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Liu, Y. (2018). Discrete Element Modelling of Geocell-Reinforced Railway Ballast and Experimental Examination of Geocell Failure Mechanisms. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/117672

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Liu, Yang. “Discrete Element Modelling of Geocell-Reinforced Railway Ballast and Experimental Examination of Geocell Failure Mechanisms.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/117672.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Liu, Yang. “Discrete Element Modelling of Geocell-Reinforced Railway Ballast and Experimental Examination of Geocell Failure Mechanisms.” 2018. Web. 19 Feb 2020.

Vancouver:

Liu Y. Discrete Element Modelling of Geocell-Reinforced Railway Ballast and Experimental Examination of Geocell Failure Mechanisms. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/117672.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Liu Y. Discrete Element Modelling of Geocell-Reinforced Railway Ballast and Experimental Examination of Geocell Failure Mechanisms. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/117672

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

5. Su, Yu. Advances in development of novel ultra-high performance concrete.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/112039

► The rising of terrorism activities has promoted fast development of new construction materials to enhance the resistance and resilience of buildings and infrastructure against blast… (more)

▼ The rising of terrorism activities has promoted fast development of new construction materials to enhance the resistance and resilience of buildings and infrastructure against blast loads. As a notable representative, ultra-high performance concrete (UHPC) has now been widely investigated by government agencies and universities. UHPC inherits positive aspects of ultra-high strength concrete (UHSC) and it is equipped with improved ductility as a result of fibre addition. These features make it an ideal construction material for bridge decks, storage halls, thin-wall shell structures, and other infrastructure against seismic, impact and blast loads. In the thesis, development of novel UHPC material is presented. The new concrete material is distinguished from previous development by the inclusion of the nanoparticles. It was noticed that addition of nanoscale size particles results in significantly improved material properties without much change of the material composition. The present study focuses on influence of fibre material addition and nanomaterial addition on mechanical properties of UHPC material. In total, three kinds of steel fibre material with varying volume fraction are considered in the material design, in combination with four different nano materials at varying weight dosages. Discussion is carried out on fibre material geometry and fraction as well as nano particle effect. Static material tests are carried out to understand material strength and ductility. Uniaxial compressive tests and flexural tensile tests reveal the exceptional material strength, ductility as well as energy absorption capability. Since the material aims at improving the structural performance under extreme loading conditions, dynamic material properties are also of significant importance. Split Hopkinson Pressure Bar (SHPB) tests are conducted on UHPC samples, dynamic compression tests and split tensile tests are studied and compared with static material strength to obtain the dynamic increase factor which is critical in the design of material and structures against dynamic loads. All the above tests can be used to qualitatively and quantitatively examine the material performance with nano material and steel fibre material addition at macroscale. To further study the influence of these materials, microscopy analysis was conducted to provide explanation of macroscopic failure phenomenon at micro-scale. Morphology of the samples was observed by Scanning Electron Microscopy (SEM). X-Ray Diffraction (XRD) instrument was used for phase analysis and semi-quantitative analysis. Elemental analysis was conducted by X-Ray Fluorescence (XRF). In SEM tests on post-damage UHPC samples, different damage modes at ITZ are identified, XRD and XRF analysis confirmed the filling and pozzolanic effect of nano particles addition. In most cases, UHPC material can be treated as homogeneous at macroscopic scale, when observed at a smaller length scale, UHPC is heterogeneous and consists of constituents including aggregate, CH crystals, C-S-H gel, water… Advisors/Committee Members: Wu, Chengqing (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: UHPC; nano; SHPB; dynamic; steel fibre; microscopy; SEM; XRD; XRF; meso-scale; Research by Publication

…tertiary institution without the prior approval of the University of Adelaide and where…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Su, Y. (2017). Advances in development of novel ultra-high performance concrete. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/112039

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Su, Yu. “Advances in development of novel ultra-high performance concrete.” 2017. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/112039.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Su, Yu. “Advances in development of novel ultra-high performance concrete.” 2017. Web. 19 Feb 2020.

Vancouver:

Su Y. Advances in development of novel ultra-high performance concrete. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/112039.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Su Y. Advances in development of novel ultra-high performance concrete. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/112039

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

6. Vu, Van D. A kinematically enhanced constitutive model for progressive damage analysis of unidirectional fiber reinforced composites.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/115375

► The application of fiber reinforced laminated composite structures has been increasing steadily in many engineering disciplines due to their high specific strength and stiffness, corrosion… (more)

▼ The application of fiber reinforced laminated composite structures has been increasing steadily in many engineering disciplines due to their high specific strength and stiffness, corrosion resistance, exceptional durability and many other attractive features over the last few decades. A comprehensive strength and failure assessment of these structures made of composite materials is extremely important for a reliable design of these structures and it has been a major focus of many researchers in this field for a long time. To the best of our knowledge, the majority of the existing studies based on macro based continuum approach are particularly focussed on capturing the effective elastic properties and final failure envelop of the composite material, while the subsequent post-yield inelastic behaviour or the entire nonlinear response is often overlooked. Composite structures with such diverse applications can be subjected to complex loading conditions such as impacts, severe dynamic loads or extreme thermal loads which can lead to a significant damage or complete failure of these structures. It is therefore essential to predict the entire nonlinear response and failure of these structures in many situations for a better design with higher confidence. This problem is quite challenging, specifically with a macro based continuum approach, as the actual failure initiates at the micro scale in the form of matrix cracking, fiber rupture or fiber-matrix interface failure which propagate gradually, accumulate together and finally manifested as macroscale structural failure. Thus tracking the details on the entire failure evolution process from microscale to macroscale is necessary for accurately modelling the structural failure. A detailed micromechanical modelling approach, where all constituents are explicitly modelled, can capture all these microscale failure processes and their evolutions in details but such modelling strategy is not computationally feasible for failure analysis for large structures due to a huge gap between micro/fiber and macro/structural scales. Thus the analysis of these structures requires an innovative modelling approach that can represent and capture the essential features of these microscale failure details, while at the same time, should be computationally efficient like a macro based continuum model for undertaking large scale structural analysis. In this study, a new three-dimensional kinematically enhanced macro-based constitutive model is developed which is applicable at the lamina/ply scale of these laminated composite structures. A novel analytical technique is developed for upscaling the nonlinear response from the fiber/micro scale to the ply scale which is the key for achieving such precise modelling of composites with feasible computational resources. The proposed approach utilized a strategy of strain field enhancements kinematically to account for different rate of deformations in the local fields within a fiber reinforced composite (FRC) ply. Based… Advisors/Committee Members: Sheikh, Abdul Hamid (advisor), Nguyen, Giang D. (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Research by publication; composite; unidirectional; damage mechanics; plasticity theory; constitutive modelling; nonlinear behaviour; thermodynamics

…must thank the School of Civil, Environmental and Mining Engineering for providing me the… …Environmental and Mining Engineering for their inspirations and positive attitudes that helped me… …concerns. I would like to thank to all my friends and fellow colleagues at the School of Civil…

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APA (6^th Edition):

Vu, V. D. (2018). A kinematically enhanced constitutive model for progressive damage analysis of unidirectional fiber reinforced composites. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/115375

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Vu, Van D. “A kinematically enhanced constitutive model for progressive damage analysis of unidirectional fiber reinforced composites.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/115375.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Vu, Van D. “A kinematically enhanced constitutive model for progressive damage analysis of unidirectional fiber reinforced composites.” 2018. Web. 19 Feb 2020.

Vancouver:

Vu VD. A kinematically enhanced constitutive model for progressive damage analysis of unidirectional fiber reinforced composites. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/115375.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Vu VD. A kinematically enhanced constitutive model for progressive damage analysis of unidirectional fiber reinforced composites. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/115375

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

7. Munoz Principe, Henry Edinson. Rock strength and deformability characterisation and assessment for drilling performance estimation.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/104725

► Rock drilling and cutting is essential in the mining industry. Rock characterisation and classification methods have been proposed to assess drilling or cutting performance. However,… (more)

▼ Rock drilling and cutting is essential in the mining industry. Rock characterisation and classification methods have been proposed to assess drilling or cutting performance. However, a unique method to relate rock characteristics to rock cutting performance has not yet been developed. This is due to the complexity of interactions among the variables involved in the drilling process encompassing not only rock properties, but also the nature of drilling. Cost-effective drilling is achievable by allocating the available gross energy towards the drilling action and, at the same time, reducing systematically that energy consumed in frictional processes inherent to tool-rock interactions. Several attempts have been made to assess drilling performance by correlating different rock properties with the drilling rate. For instance, rock texture, grain size, Unconfined Compressive Strength (UCS), Mohs hardness and rock mass structural parameters, and others have been used to build a number of drillability indices. However, not only rock properties, but also different sets of drilling parameters and drilling techniques have an impact on the drilling performance and efficiency of the process. On one hand, to predict rock drilling performance and optimisation of drilling operation, tool-rock interaction laws, i.e. the relations between forces acting on the tool in contact with rock, are essential. For instance, through tool-rock interaction laws, it was found that during rotary drilling, the energy consumed in pure cutting action of rock is measured by the intrinsic specific energy. In the case of percussive drilling, tool-rock interactions are focused mostly in the prediction of the penetration rate and the optimum thrust. On the other hand, rock failure characterised by rock brittleness is a concept yet to be investigated as there is not a unique criterion able to describe rock brittleness quantitatively nor consensus about the most suitable and reliable brittleness index to apply to different rock engineering works encountered in the field. A new brittleness index upon fracture strain-energy quantities extracted from the area under complete stress-strain curve of rocks in uniaxial compressive tests is proposed herein to study drilling performance by rock brittleness capacity. This brittleness index takes into account post-peak instability in uniaxial compression as post-peak instability of rock during compression can be treated as a manifestation of rock brittleness. That is, an increase in the post-peak energy indicates an increase of stability (i.e. a decrease in brittleness or increase in ductility). In the same manner, a dramatic decrease of post-peak energy indicates less stability of the failure process (i.e. an increase in brittleness). In this view, advanced laboratory experiments on strength and deformability of soft-to-hard rock types (UCS is ranging from 7 to 215 MPa) were carried out. The compressive tests complied with the application of a prescribed constant lateral strain-rate as a feedback signal to control the… Advisors/Committee Members: Chanda, Emmanuel (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: strength; deformability; drilling performance; Research by Publication

…Hillis, currently Professor at the Australian School of Petroleum at the University of Adelaide… …the University of Adelaide and Chair of the Educational Committee of Deep Exploration…

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APA (6^th Edition):

Munoz Principe, H. E. (2017). Rock strength and deformability characterisation and assessment for drilling performance estimation. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/104725

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Munoz Principe, Henry Edinson. “Rock strength and deformability characterisation and assessment for drilling performance estimation.” 2017. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/104725.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Munoz Principe, Henry Edinson. “Rock strength and deformability characterisation and assessment for drilling performance estimation.” 2017. Web. 19 Feb 2020.

Vancouver:

Munoz Principe HE. Rock strength and deformability characterisation and assessment for drilling performance estimation. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/104725.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Munoz Principe HE. Rock strength and deformability characterisation and assessment for drilling performance estimation. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/104725

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

8. Mohseni, Hasan. Damage identification in FRP-retrofitted concrete structures using linear and nonlinear guided waves.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/115872

► Structural health monitoring (SHM) involves the implementation of damage identification methods in engineering structures to ensure structural safety and integrity. The paramount importance of SHM… (more)

▼ Structural health monitoring (SHM) involves the implementation of damage identification methods in engineering structures to ensure structural safety and integrity. The paramount importance of SHM has been recognised in the literature. Among different damage identification methods, guided wave approach has emerged as a revolutionary technique. Guided wave-based damage identification has been the subject of intensive research in the past two decades. Meanwhile, applications of fibre reinforced polymer (FRP) composites for strengthening and retrofitting concrete structures have been growing dramatically. FRP composites offer high specific stiffness and high specific strength, good resistance to corrosion and tailorable mechanical properties. On the other hand, there are grave concerns about longterm performance and durability of FRP applications in concrete structures. Therefore, reliable damage identification techniques need to be implemented to inspect and monitor FRPretrofitted concrete structures. This thesis aims to explore applications of Rayleigh wave for SHM in FRP-retrofitted concrete structures. A three-dimensional (3D) finite element (FE) model has been developed to simulate Rayleigh wave propagation and scattering. Numerical simulation results of Rayleigh wave propagation in the intact model (without debonding at FRP/concrete interface) are verified with analytical solutions. Propagation of Rayleigh wave in the FRP-retrofitted concrete structures and scattering of Rayleigh waves at debonding between FRP and concrete are validated with experimental measurements. Very good agreement is observed between the FE results and experimental measurements. The experimentally and analytically validated FE model is then used in numerical case studies to investigate the scattering characteristic. The scattering directivity pattern (SDP) of Rayleigh wave is studied for different debonding size to wavelength ratios and in both backward and forward scattering directions. The suitability of using bonded mass to simulate debonding in the FRP-retrofitted concrete structures is also investigated. Besides, a damage localisation method is introduced based on the time-of-flight (ToF) of the scattered Rayleigh wave. Numerical case studies, involving different locations and sizes of debonding, are presented to validate the proposed debonding localisation method. Nonlinear ultrasonics is a novel and attractive concept with the potential of baseline-free damage detection. In this thesis, nonlinear Rayleigh wave induced at debondings in FRPretrofitted concrete structures, is studied in detail. Numerical results of nonlinear Rayleigh wave are validated with experimental measurements. The study considers both second and third harmonics of Rayleigh wave. A very good agreement is observed between numerical and experimental results of nonlinear Rayleigh wave. Directivity patterns of second and third harmonics for different debonding size to the wavelength ratios, and in both backward and forward scattering… Advisors/Committee Members: Ng, Alex Ching-Tai (advisor), Ozbakkaloglu, Togay (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: nonlinear guided waves; FRP-retrofitted concrete; higher harmonic; debonding; damage identification

10 more images…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mohseni, H. (2018). Damage identification in FRP-retrofitted concrete structures using linear and nonlinear guided waves. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/115872

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Mohseni, Hasan. “Damage identification in FRP-retrofitted concrete structures using linear and nonlinear guided waves.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/115872.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Mohseni, Hasan. “Damage identification in FRP-retrofitted concrete structures using linear and nonlinear guided waves.” 2018. Web. 19 Feb 2020.

Vancouver:

Mohseni H. Damage identification in FRP-retrofitted concrete structures using linear and nonlinear guided waves. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/115872.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mohseni H. Damage identification in FRP-retrofitted concrete structures using linear and nonlinear guided waves. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/115872

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

9. Dragos, Jonathon. New dynamic analysis techniques for structural members subjected to blast loads.

Degree: 2014, University of Adelaide

URL: http://hdl.handle.net/2440/98715

► This thesis contains a number of journal papers which aim to extend, or produce new, analyses techniques for determining the response of structural members subjected… (more)

▼ This thesis contains a number of journal papers which aim to extend, or produce new, analyses techniques for determining the response of structural members subjected to blasts. Within the first portion of the thesis, a new approach is provided which extends upon the concept of the normalised, or non-dimensional, pressure impulse (PI) curve, allowing it to be applied to determine the response of structural members subjected to blasts occurring in vented and unvented confined environments. As a confined blast load is highly irregular, containing multiple peaks and long duration gas pressures, a method for simplifying the confined blast load is proposed. Then, an entirely new general approach for determining normalised PI curves is developed and presented. It is shown that, due to its generality, it can account for any pulse load shape. It is also shown that other curve-fitting techniques typically used to determine normalised PI curves, while being suitable for external blast loads, cannot be applied to the more abstract pulse load shapes associated with confined blast loads. Then, the newly proposed general approach is applied to, and validated for, vented confined blast loads. Furthermore, the entire concept of a PI curve is extended so that an infinitely long duration unvented confined blast load, having an infinite impulse, can be analysed using a PI diagram. A one dimensional (1D) finite element model (FEM) is then adopted for further studies, due to its inherent accuracy and stability despite its numerically efficiency. As the 1D FEM can accurately model the global dynamic response of an entire structural member, it does not suffer from the limitations of more commonly used simplified analysis techniques, such as the single degree of freedom (SDOF) method. Firstly, a segmental moment-rotation model is incorporated into the 1D FEM to accurately analyse the response of reinforced concrete (RC) beams and slabs subjected to blasts. The model, as a whole, can accurately simulate important RC behaviour, such as slipping of steel reinforcement within concrete and softening of concrete in compression, despite being numerically efficient. Furthermore, the 1D FEM is used to determine PI curves for steel columns under various levels of axial loading. This study is then used to validate a newly developed simple SDOF approach for determining PI curves for steel columns under axial loading. Despite the simplicity of the approach, it is shown to accurately account for the new failure mechanism of global instability and PΔ effects, all caused by the axial load. Finally, the 1D FEM is used to undertake a parametric study on RC slabs to determine the influence of the flexural behaviour and geometrical properties on the direct shear response. The results provided in this final study aim to be a starting point for determining more sophisticated simplified methods, such as a new SDOF method or normalised PI curves, for analysing the direct shear response of RC beams and slabs. Advisors/Committee Members: Wu, Chengqing (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: blast loads; structural response; pressure impulse diagram; numerical model

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Dragos, J. (2014). New dynamic analysis techniques for structural members subjected to blast loads. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/98715

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Dragos, Jonathon. “New dynamic analysis techniques for structural members subjected to blast loads.” 2014. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/98715.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Dragos, Jonathon. “New dynamic analysis techniques for structural members subjected to blast loads.” 2014. Web. 19 Feb 2020.

Vancouver:

Dragos J. New dynamic analysis techniques for structural members subjected to blast loads. [Internet] [Thesis]. University of Adelaide; 2014. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/98715.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Dragos J. New dynamic analysis techniques for structural members subjected to blast loads. [Thesis]. University of Adelaide; 2014. Available from: http://hdl.handle.net/2440/98715

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

10. Ranasinghe, R. A. Tharanga Madhushani. Prediction of the Effectiveness of Rolling Dynamic Compaction Using Artificial Intelligence Techniques and In Situ Soil Test Data.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/118672

► The research presented in this thesis focuses on developing predictive tools to forecast the effectiveness of rolling dynamic compaction (RDC) in different ground conditions. Among… (more)

▼ The research presented in this thesis focuses on developing predictive tools to forecast the effectiveness of rolling dynamic compaction (RDC) in different ground conditions. Among many other soil compaction methods, RDC is a widespread technique, which involves impacting the ground with a heavy (6–12 tonnes) non-circular (3-, 4- and 5- sided) module. It provides the construction industry with an improved ground compaction capability, especially with respect to a greater influence depth and a higher speed of compaction, resulting in increased productivity when compared with traditional compaction equipment. However, to date, no rational means are available for obtaining a priori estimation of the degree of densification or the extent of the influence depth by RDC in different ground conditions. In addressing this knowledge gap, the research presented in this thesis develops robust predictive models to forecast the performance of RDC by means of the artificial intelligence (AI) techniques in the form of artificial neural networks (ANNs) and linear genetic programming (LGP), which have already been proven to be successful in a wide variety of forecasting applications in geotechnical engineering aspects. This study is focussed solely on the 4-sided, 8 tonne impact roller (BH-1300) and the AI-based models incorporate comprehensive databases consisting of in situ soil test data; specifically cone penetration test (CPT) and dynamic cone penetration (DCP) test data obtained from many ground improvement projects involving RDC. Thus, altogether, two distinct sets of optimal models: two involving ANNs – one for the CPT and the other for the DCP; and two LGP models – again, one for the CPT and the other for the DCP – are presented. The accuracy and the reliability of the optimal model predictions are assessed by subjecting them to various performance measures. Furthermore, each of the selected optimal models are examined in a parametric study, by which the generalisation ability and the robustness of the models are confirmed. In addition, the performance of the optimal ANN and LGP-based models, as well as other aspects, are compared with each other in order to assess the suitability and shortcomings of each. Consequently, a recommendation has been made of the most feasible approach for predicting the effectiveness of RDC in different ground conditions with respect to CPT and DCP test data. The models have also been disseminated via a series of mathematical formulae and/or programming code to facilitate their application in practice. It is demonstrated that the developed optimal models are accurate and reliable over a range of soil types, and thus, have been recommended with confidence. As such, the developed models provide preliminary estimates of the density improvement in the ground based on the subsurface conditions and the number of roller passes. Therefore, it is considered that the models are beneficial during the pre-planning stages, and may replace, or at the very least augment, the necessity for RDC field trials prior… Advisors/Committee Members: Jaksa, Mark (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Rolling dynamic compaction; artificial neural networks; linear genetic programming

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APA (6^th Edition):

Ranasinghe, R. A. T. M. (2017). Prediction of the Effectiveness of Rolling Dynamic Compaction Using Artificial Intelligence Techniques and In Situ Soil Test Data. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/118672

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Ranasinghe, R A Tharanga Madhushani. “Prediction of the Effectiveness of Rolling Dynamic Compaction Using Artificial Intelligence Techniques and In Situ Soil Test Data.” 2017. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/118672.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Ranasinghe, R A Tharanga Madhushani. “Prediction of the Effectiveness of Rolling Dynamic Compaction Using Artificial Intelligence Techniques and In Situ Soil Test Data.” 2017. Web. 19 Feb 2020.

Vancouver:

Ranasinghe RATM. Prediction of the Effectiveness of Rolling Dynamic Compaction Using Artificial Intelligence Techniques and In Situ Soil Test Data. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/118672.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Ranasinghe RATM. Prediction of the Effectiveness of Rolling Dynamic Compaction Using Artificial Intelligence Techniques and In Situ Soil Test Data. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/118672

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

11. Xia, Ye. Cladding Protection of Reinforced Concrete Structural Members against Blast Loading.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/119190

► With the increasing threat of explosions on infrastructures across the world, the protective techniques against blast loading on existing structures have become more and more… (more)

Subjects/Keywords: Aluminium foam; optimisation; blast load; graded density

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APA (6^th Edition):

Xia, Y. (2017). Cladding Protection of Reinforced Concrete Structural Members against Blast Loading. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/119190

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Xia, Ye. “Cladding Protection of Reinforced Concrete Structural Members against Blast Loading.” 2017. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/119190.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Xia, Ye. “Cladding Protection of Reinforced Concrete Structural Members against Blast Loading.” 2017. Web. 19 Feb 2020.

Vancouver:

Xia Y. Cladding Protection of Reinforced Concrete Structural Members against Blast Loading. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/119190.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Xia Y. Cladding Protection of Reinforced Concrete Structural Members against Blast Loading. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/119190

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

12. Wright, David Peter. Influence diagnostics in hydrological modeling.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/119251

► Accurate hydrological model predictions play an important role in designing infrastructure for domestic water supply, agriculture, industry, and flood and drought protection. A key step… (more)

▼ Accurate hydrological model predictions play an important role in designing infrastructure for domestic water supply, agriculture, industry, and flood and drought protection. A key step in model development is model calibration where hydrologists fit a model to historical data to make predictions into the future. The original contribution to knowledge of this thesis is to evaluate and develop influence diagnostics to understand the extent to which model calibration outcomes are determined by a small number of data points that may be erroneous or unrepresentative of overall catchment behaviour. Influence diagnostics can be implemented to describe changes in model predictions, calibrated parameters and model performance. Broadly, these diagnostics can be categorised into two different classes; “case-deletion” influence diagnostics and “regressiontheory” influence diagnostics. Although influence diagnostics have previously been applied to a small number of hydrological studies, there is a need to address the following two major limitations with the currently available influence diagnostics before they can be applied to broader hydrological applications: 1. Case-deletion influence diagnostics are too computationally expensive to apply in hydrological modelling applications because of the length of data and therefore number of model recalibrations that are required (e.g. 10 years requires approximately 3650 model re-calibrations). 2. Regression theory influence diagnostics are computationally efficient, but only linear Cook’s distance has been applied which has strong assumptions of linear model response and Gaussian residual error that are typrically not valid in hydrological modeling. This thesis by publication presents three papers in Chapter 2 to Chapter 4. The first paper investigates the application of influence diagnostics in the context of a series of common hydrological case-studies including a rating curve model and a daily hydrological model with two years of calibration data. In the second paper we generalise regression xii theory influence diagnostics and evaluate the performance in reproducing the computationally expensive case-deletion influence diagnostics on eleven case studies with a variety of model structures and inference scenarios including: nonlinear model response, heteroscedastic residual errors, data uncertainty and Bayesian priors. Finally, in the third paper we present a hybrid framework for influence assessment that combines the strengths of the two classes of influence diagnostics in order to overcome the key limitations listed above. The hybrid framework presented in the third paper in this thesis will provide a foundation for all hydrological modellers to have greater insight into the influence of individual data points on model calibration, thereby providing a basis for identifying disinformative points or understanding how sensitive model predictions are to a small proportion of the dataset. xiii Advisors/Committee Members: Thyer, Mark (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Hydrologic model calibration; Influence diagnostics; Cook's distance

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Wright, D. P. (2017). Influence diagnostics in hydrological modeling. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/119251

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wright, David Peter. “Influence diagnostics in hydrological modeling.” 2017. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/119251.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wright, David Peter. “Influence diagnostics in hydrological modeling.” 2017. Web. 19 Feb 2020.

Vancouver:

Wright DP. Influence diagnostics in hydrological modeling. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/119251.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wright DP. Influence diagnostics in hydrological modeling. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/119251

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

13. Mir, Arash. A Thermodynamic Approach to Modelling Brittle-Ductile and Localised Failure of Rocks Using Damage Mechanics and Plasticity Theory.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/119263

► Recent advances in computational mechanics and numerical simulation techniques enable more efficient and realistic geotechnical and mining designs and analyses. A successful numerical simulation requires… (more)

▼ Recent advances in computational mechanics and numerical simulation techniques enable more efficient and realistic geotechnical and mining designs and analyses. A successful numerical simulation requires a robust and rigorous constitutive model, which is capable of predicting the most fundamental features of material behaviour. In conjunction with numerical simulations, the complex behaviour observed in geomaterials also encourages the development of more capable and realistic constitutive models. The key aspects of developing constitutive models for rocks are to capture the essential features of rock deformation and failure, observed in experimental studies or in the field. These features include brittle behaviour, which refers to a sudden post-peak strain softening, ductile behaviour which is interpreted as the capacity for undergoing substantial inelastic deformation without gross fracturing and the transitional state between these two regimes of behaviour. Another important behavioural feature of rocks and also other geomaterials is the localisation of deformation within a narrow band. Upon the onset of localisation, the homogeneity of stress and strain fields is lost and any macroscopic definition of stress and strain is no longer physically meaningful. It is also essential for any constitutive model to be thermodynamically admissible. The focus of this study is on the development of thermodynamically consistent constitutive models for rocks. The development of the constitutive models is carried out within the framework of generalised thermodynamics to ensure the thermodynamic admissibility of the models. The key feature of the generalised thermodynamic framework is that the entire constitutive relations can be derived by explicitly defining two scalar functions, namely, an energy potential and a dissipation function. In this study, it is demonstrated that how the most fundamental mechanisms of deformation and energy dissipation can be incorporated into the model formulation by enriching the two thermodynamic functions with extra kinematic constraint equations. The theories of plasticity and continuum damage mechanics are also used to describe the mechanisms of energy dissipation and deformation. By adopting the thermodynamic approach, the coupling between damage and plasticity is specified in the formulation of the dissipation function, which is subsequently transformed (using a degenerate Legendre transformation) to a single generalised yield function. This method for coupling damage and plasticity facilitates the numerical implementation of the models as a single yield function controls the simultaneous evolution of damage and plastic strains. An important aspect of the coupled-damage plasticity models developed in this study is that, in accordance with experimental observations, the initial yield surface is transformed to a final failure envelope due to the evolution of the internal variables of the models. Owing to this feature of the models, rock mechanical behaviour under various stress states can be… Advisors/Committee Members: Nguyen, Giang (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Thermodynamics; brittle-ductile; rocks; damage; plasticity

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Mir, A. (2017). A Thermodynamic Approach to Modelling Brittle-Ductile and Localised Failure of Rocks Using Damage Mechanics and Plasticity Theory. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/119263

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Mir, Arash. “A Thermodynamic Approach to Modelling Brittle-Ductile and Localised Failure of Rocks Using Damage Mechanics and Plasticity Theory.” 2017. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/119263.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Mir, Arash. “A Thermodynamic Approach to Modelling Brittle-Ductile and Localised Failure of Rocks Using Damage Mechanics and Plasticity Theory.” 2017. Web. 19 Feb 2020.

Vancouver:

Mir A. A Thermodynamic Approach to Modelling Brittle-Ductile and Localised Failure of Rocks Using Damage Mechanics and Plasticity Theory. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/119263.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Mir A. A Thermodynamic Approach to Modelling Brittle-Ductile and Localised Failure of Rocks Using Damage Mechanics and Plasticity Theory. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/119263

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

14. Guo, Danlu. Practical Implementation of the Scenario-Neutral Approach to Climate Impact Assessments for Hydrological Systems.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/119091

► Understanding the impacts of climate change has particular significance for the future planning, design and operation of water resource systems. Scenario-neutral approaches are used increasingly… (more)

▼ Understanding the impacts of climate change has particular significance for the future planning, design and operation of water resource systems. Scenario-neutral approaches are used increasingly to assess these possible impacts. These approaches allow water resource systems to be assessed independently of climate change projections, instead focusing on the sensitivity of specific systems to a large number of plausible climate change conditions. Once developed, these approaches can be used to better understand water resource system vulnerability, and provides a mechanism to incorporate multiple lines of evidence on possible future climatic changes into the climate impact assessment. The aim of this research therefore is to improve the practical implementation of scenario-neutral approaches by focusing on two key limitations: (1) limited capacity to generate a comprehensive climate exposure space to describe a large number of plausible future climate conditions; and (2) lack of understanding of how the physical process representation in rainfall-runoff models can affect future runoff projections. The first limitation was addressed by developing an inverse approach to generate a climate exposure space that can represent a range of plausible future changes in rainfall and evapotranspiration. This is achieved by firstly identifying a set of climate variables (e.g. rainfall, temperature) and attributes of those variables (e.g. annual average, extremes) that might change in the future, and then modifying the parameters of a weather generator to perturb these variables and attributes within plausible ranges. This overcomes a long-standing problem in scenario-neutral studies, which have tended to focus only on a small subset of variables and attributes that might change in the future. The second limitation was addressed by examining the impact of alternative evapotranspiration representations within rainfall-runoff models, and assessing how this representation interacts with future evapotranspiration and runoff projections. The research showed that although the calibration and validation performance of alternative rainfall-runoff models may be similar under historical climate conditions, the process representation can have a significant impact on future projections, highlighting the importance of model selection as part of the climate impact assessment process. The outcomes of this research are demonstrated by implementing the enhanced scenario-neutral approach to a case study in Scott Creek catchment in South Australia. The results are used to show how different measures of runoff change as a function of different climate perturbations, and the climate variables most important for the system under plausible future climate conditions. This research therefore provides guidance for the future implementations of scenario-neutral framework, and thus greatly extends the applicability of this framework to a larger range of climate impact assessment problems. Advisors/Committee Members: Westra, Seth (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Scenario-neutral approach; climate impact assessments; climate exposure space; evapotranspiration; rainfall-runoff modelling

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Guo, D. (2017). Practical Implementation of the Scenario-Neutral Approach to Climate Impact Assessments for Hydrological Systems. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/119091

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Guo, Danlu. “Practical Implementation of the Scenario-Neutral Approach to Climate Impact Assessments for Hydrological Systems.” 2017. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/119091.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Guo, Danlu. “Practical Implementation of the Scenario-Neutral Approach to Climate Impact Assessments for Hydrological Systems.” 2017. Web. 19 Feb 2020.

Vancouver:

Guo D. Practical Implementation of the Scenario-Neutral Approach to Climate Impact Assessments for Hydrological Systems. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/119091.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Guo D. Practical Implementation of the Scenario-Neutral Approach to Climate Impact Assessments for Hydrological Systems. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/119091

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

15. Addo Junior, Emmanuel. Multivariate Modelling of Geological and Geometallurgical Variables.

Degree: 2019, University of Adelaide

URL: http://hdl.handle.net/2440/120164

► The mining and minerals industry is confronted with several challenges that were not common some decades ago. Deep-seated and complex orebodies, low metal grades, and… (more)

▼ The mining and minerals industry is confronted with several challenges that were not common some decades ago. Deep-seated and complex orebodies, low metal grades, and fluctuating commodity prices have an increasingly high impact on the mining industry, potentially reducing profit margins. It follows that accurate modelling of geological and geometallurgical variables is needed to reduce risks associated with most mineral prospects. This modelling needs to include uncertainty in predictions, as well as outcomes, so that mining companies can use value at risk, for example, to make informed business decisions. This thesis, comprises three journal papers and one conference paper. Several mathematical formulations have been used to model geological and geometallurgical variables. These novel modelling methodologies provides more versatile modelling techniques to traditional modelling techniques which are currently employed in the mining and minerals industry. In Chapter 2 (Paper 1) and Chapter 3 (Paper 2), spatial pair-copula models are used to predict the geological grades of an anisotropic gold deposit within and outside a main field. These models are compared with a traditional kriging approach and results show that pair-copulas models provide improved modelling of error structure than kriging. In Chapter 4 (Paper 3), different trivariate copulas were used to model and predict geological variables from a drill core. The models provided better estimates and prediction intervals of geological variables. In general, geological variables have a large number of outlying values and also exhibit tail dependence. Copulas provide a means of dealing with these practical issues. D-vine copula models, which are able to address the massive multivariate nature and non-linear bivariate relationships of geometallurgical variables, are employed to model geometallurgical variables. In most cases, geometallurgical variables have several missing data, which makes modelling and prediction of these variables difficult. Chapter 5 (Paper 4), a novel data imputation algorithm is developed as part of this thesis to address the issue of missing data of geometallurgical variables. The outcomes of this thesis are an improved geostatistical modelling framework and novel data imputation algorithm techniques, providing better estimates and prediction intervals for geological and geometallurgical variables, and with demonstrated application to practical mining case studies. Advisors/Committee Members: Leonard, Michael (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: copulas; geostatistical modelling; kriging; mining; geometallurgy; regression; pair-copulas

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APA (6^th Edition):

Addo Junior, E. (2019). Multivariate Modelling of Geological and Geometallurgical Variables. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/120164

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Addo Junior, Emmanuel. “Multivariate Modelling of Geological and Geometallurgical Variables.” 2019. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/120164.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Addo Junior, Emmanuel. “Multivariate Modelling of Geological and Geometallurgical Variables.” 2019. Web. 19 Feb 2020.

Vancouver:

Addo Junior E. Multivariate Modelling of Geological and Geometallurgical Variables. [Internet] [Thesis]. University of Adelaide; 2019. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/120164.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Addo Junior E. Multivariate Modelling of Geological and Geometallurgical Variables. [Thesis]. University of Adelaide; 2019. Available from: http://hdl.handle.net/2440/120164

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

16. Di Matteo, Michael. Multiobjective Planning and Design of Distributed Stormwater Harvesting and Treatment Systems through Optimization and Visual Analytics.

Degree: 2016, University of Adelaide

URL: http://hdl.handle.net/2440/119621

► Stormwater harvesting (SWH) is an important water sensitive urban design (WSUD) approach that provides an alternate water source and/or improves runoff quality through stormwater best… (more)

▼ Stormwater harvesting (SWH) is an important water sensitive urban design (WSUD) approach that provides an alternate water source and/or improves runoff quality through stormwater best management practice technologies (BMPs). Through integrated SWH system design at the development scale practitioners must account for trade-offs between cost, harvested volume, and water quality improvement performance which are usually dependent on design decisions for the type, size, and spatial distribution of BMPs. In catchment management planning, additional objectives such as catchment vegetation improvement and public recreation benefit need to be maximized for a catchment region within a limited budget. As such, planning and design of SWH systems with distributed BMPs is a complex problem that requires optimal allocation of limited resources to maximize multiple benefits. In this thesis, two innovative formal optimization approaches are presented for formulating and identifying optimal solutions to problems requiring distributed BMPs. Firstly, a multiobjective optimization framework is presented and applied to a case study for the conceptual design of integrated systems of BMPs for stormwater harvesting. The aim of this work is to develop a conceptual design modelling framework that handles the optimal placement of stormwater harvesting (SWH) infrastructure within an urban development. The framework produces preliminary SWH system designs representing optimal trade-offs between cost, water harvesting, and water quality improvement measures. Secondly, a many (>3) -objective optimization framework is presented and applied to a case study for catchment planning requiring the selection of a portfolio of distributed BMP projects. The framework produces portfolios that are optimal with respect to four objectives, and enables exploration of the many-objective trade-off surface using interactive visual analytics. In addition, a multi-stakeholder method is presented, which enables catchment managers and local government authorities to identify solutions that represent a compromise between 16 objectives and eight optimization problem representations using interactive visual analytics to encourage a negotiated solution. This thesis contains one paper accepted in the Journal of Water Resources Planning and Management (Paper 1), and one paper submitted (Paper 2), and one paper to be submitted (Paper 3) to peer-reviewed journals in the field of water resources management. Advisors/Committee Members: Dandy, Graeme (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Stormwater management; Optimization; Visualisation; Water sensitive urban design

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Di Matteo, M. (2016). Multiobjective Planning and Design of Distributed Stormwater Harvesting and Treatment Systems through Optimization and Visual Analytics. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/119621

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Di Matteo, Michael. “Multiobjective Planning and Design of Distributed Stormwater Harvesting and Treatment Systems through Optimization and Visual Analytics.” 2016. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/119621.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Di Matteo, Michael. “Multiobjective Planning and Design of Distributed Stormwater Harvesting and Treatment Systems through Optimization and Visual Analytics.” 2016. Web. 19 Feb 2020.

Vancouver:

Di Matteo M. Multiobjective Planning and Design of Distributed Stormwater Harvesting and Treatment Systems through Optimization and Visual Analytics. [Internet] [Thesis]. University of Adelaide; 2016. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/119621.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Di Matteo M. Multiobjective Planning and Design of Distributed Stormwater Harvesting and Treatment Systems through Optimization and Visual Analytics. [Thesis]. University of Adelaide; 2016. Available from: http://hdl.handle.net/2440/119621

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

17. Zhou, Changtai. Theoretical and numerical modelling of the anisotropic behaviour of jointed rocks.

Degree: 2019, University of Adelaide

URL: http://hdl.handle.net/2440/119874

► In nature, various forms of rock anisotropy are widely pre-existing discontinuities such as bedding planes, joints, weak layers and cleavages. Rock anisotropic characteristics are in… (more)

▼ In nature, various forms of rock anisotropy are widely pre-existing discontinuities such as bedding planes, joints, weak layers and cleavages. Rock anisotropic characteristics are in general critical for the stability of surface or underground rock excavations. The goal of this work is to investigate the anisotropic behaviour of jointed rock masses using theoretical and numerical modelling methods. In particular, discrete element modelling using flat jointed bonded particle model (FJM) was used in this research. A systematic micro-parameter calibration method for FJM was proposed first in this work to overcome the limitations of traditional approach, which essentially is a time-consuming tedious trial and error process. The relationships between the FJM micro-parameters and constitutive parameters, as well as macro-mechanical rock properties were first established through dimensionless analysis. Sensitivity and regression analyses were then conducted to quantify their relationships, using results from numerical simulations. The proposed method was demonstrated to be robust and effective based on the macro-mechanical property validation of four different types of rocks. The application of FJM to capture the load rate-dependent mechanical properties of rock materials was investigated. The results were cross-validated with experimental measurements, which indicated that FJM can model the dynamic behaviour of rocks from quasi-static to medium strain rate range. FJM, in combination with smooth joint model (SJM) used to model discontinuities, were then used to study the dynamic behaviour of rocks with a persistent joint at different orientations. A strength prediction model for dynamic UCS of a specimen containing a persistent joint at different orientations were proposed and the coefficients of the proposed equation were quantified based on numerical simulation results. The proposed model was shown to be capable of predicting VII the rate-dependent UCS of a jointed rock. Finally, the strength reduction of a jointed rock was further investigated using the statistical damage model approach based on the commonly used Weibull distribution, where the Jaeger’s and modified Hoek-Brown failure criteria were incorporated in the derived model. The proposed damage model was validated using published experimental data and numerical simulation results of FJM. Results indicated that parameter m only depends on strain parameter k, which is directly proportional to the increase of the failure strain, while parameter F0 is indirectly related to the strength of the jointed rock. In addition, joint stiffness can be easily incorporated in the proposed damage model, which has significant influence on the damage variable D, damage evolution rate Dr and rock mass deformation modulus. Outcomes of this research help us to understand better the influences of discontinuities on the mechanical behaviour of jointed rock masses. Advisors/Committee Members: Xu, Chaoshui (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: discrete element method; bonded-particle model; loading rate; anisotropy; damage model

10 more images…

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Zhou, C. (2019). Theoretical and numerical modelling of the anisotropic behaviour of jointed rocks. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/119874

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhou, Changtai. “Theoretical and numerical modelling of the anisotropic behaviour of jointed rocks.” 2019. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/119874.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhou, Changtai. “Theoretical and numerical modelling of the anisotropic behaviour of jointed rocks.” 2019. Web. 19 Feb 2020.

Vancouver:

Zhou C. Theoretical and numerical modelling of the anisotropic behaviour of jointed rocks. [Internet] [Thesis]. University of Adelaide; 2019. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/119874.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhou C. Theoretical and numerical modelling of the anisotropic behaviour of jointed rocks. [Thesis]. University of Adelaide; 2019. Available from: http://hdl.handle.net/2440/119874

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

18. Knight, Daniel. The generic simulation of reinforced concrete beams with prestressing and external reinforcement.

Degree: 2014, University of Adelaide

URL: http://hdl.handle.net/2440/85233

► This thesis presents a series of journal papers in which a new segmental moment-rotation (M/Ө) approach is developed for simulating the instantaneous and sustained loading… (more)

▼ This thesis presents a series of journal papers in which a new segmental moment-rotation (M/Ө) approach is developed for simulating the instantaneous and sustained loading behaviour of reinforced concrete (RC) beams with prestressing and external reinforcement. The M/Ө approach is formed on the fundamental Euler-Bernoulli postulation that plane sections remain plane, but not necessarily on the Euler-Bernoulli corollary of a linear strain profile. Further adaption of the well-established mechanics of partial-interaction (PI) theory introduces a fundamental baseline concept in which residual strains due to time-effects, thermal gradients and prestressing are accounted for in simulating the formation and gradual widening of cracks and the associated effects of tension-stiffening allowing for bond-slip. The effects of concrete softening are incorporated into the M/Ө approach through a size dependent concrete stress-strain relationship based on the mechanics of shear-friction theory which simulates the behaviour of a member once a concrete softening wedge forms. The approach is shown to be able to quantify segmental equivalent flexural rigidities for both instantaneous and time-dependent behaviour, thus removing the reliance on empiricism in quantifying the effects of concrete cracking and softening. In defining the segmental equivalent flexural rigidities of RC beams with both post-tensioned and pre-tensioned reinforcement it is shown how the approach is used to quantify the load-deflection behaviour of the entire member through the application of conventional analysis techniques. The established M/Ө approach is then generically applied to RC beams with both prestressed fibre reinforced polymer (FRP) and steel reinforcement in quantifying the beams instantaneous and sustained loading behaviour through being able to accommodate any conventional method of quantifying the time-dependent parameters. Thus the broad application of the M/Ө approach provides a novel method of simulating, through mechanics, the full-range of behaviour of a prestressed beam, that is from prestress application through serviceability loading and to collapse. Moreover, the reliance on empiricisms, as typically relied upon in standard analysis methods, are removed with the only empirical components required being in defining the material properties. Having established the M/Ө approach for the instantaneous and sustained loading of conventional prestressed beams, the approach is extended to simulate the behaviour of RC beams with unbonded post-tensioned FRP and steel tendons. Through understanding the individual segmental behaviour, a global approach is introduced in which the behaviour of the unbonded reinforcement can be quantified from the deformation based analysis. The approach is then further extended to incorporate the analysis of RC beams with mechanical-fastened (MF) FRP allowing for the PI behaviour at the fasteners. This extension forms the basis of a generic technique which can subsequently be used in the design of MF systems, with and… Advisors/Committee Members: Oehlers, Deric John (advisor), Mohamed Ali, M. S. (advisor), Visintin, Phillip (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: numerical analysis; RC; FRP; prestressing

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Knight, D. (2014). The generic simulation of reinforced concrete beams with prestressing and external reinforcement. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/85233

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Knight, Daniel. “The generic simulation of reinforced concrete beams with prestressing and external reinforcement.” 2014. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/85233.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Knight, Daniel. “The generic simulation of reinforced concrete beams with prestressing and external reinforcement.” 2014. Web. 19 Feb 2020.

Vancouver:

Knight D. The generic simulation of reinforced concrete beams with prestressing and external reinforcement. [Internet] [Thesis]. University of Adelaide; 2014. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/85233.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Knight D. The generic simulation of reinforced concrete beams with prestressing and external reinforcement. [Thesis]. University of Adelaide; 2014. Available from: http://hdl.handle.net/2440/85233

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

19. Qian, Qian. Relationship between input and output : a systematic study of the stability of highly fractured rock slopes using the Hoek-Brown strength criterion.

Degree: 2013, University of Adelaide

URL: http://hdl.handle.net/2440/82544

► Rock slope stability is a particularly important topic in rock engineering. The circular failure of highly fractured rock slopes is a critical failure mode that… (more)

▼ Rock slope stability is a particularly important topic in rock engineering. The circular failure of highly fractured rock slopes is a critical failure mode that can cause severe damage. Over the past decades, significant research has been devoted to soil slopes and failure modes of rock slopes controlled by discontinuities. However, there have been few attempts to systematically study the circular failure mode of rock slopes. Circular failure is controlled by the strength of the rock mass. While the strength of a rock mass is difficult to measure directly, the Hoek-Brown (HB) strength criterion has proved effective and convenient for its estimation. This research presents a systematic study of the stability of highly fractured rock slopes using the HB strength criterion. Both deterministic analyses and probabilistic analyses are included. The relationship between the input (GSI, mi, σci, and their variability) and the output, Factor of Safety (FS) and Probability of Failure (PF), is investigated. Slide6.0 and a limit equilibrium model programmed in Matlab are used for FS calculations; Monte Carlo simulations are applied for PF calculations. The deterministic analysis aims to characterise the sensitivity of FS to the changes in HB parameters (FS sensitivity). A sensitivity graph analysis and an equation fitting analysis are developed. The sensitivity graph analysis displays the relationship between HB parameters and FS directly. The equation fitting analysis fits a large amount of data generated by Slide6.0 with an equation connecting HB parameters and FS, and then determines FS sensitivity from the derivatives of this equation with respect to HB parameters. It is found that slopes with the same geometry and the same FS (but different combinations of HB parameters) can have quite different sensitivity and GSI is the most critical parameter in this respect. With the increase in GSI, FS becomes increasingly sensitive to the change in GSI and that in σci. The probabilistic analysis investigates the relationship between the variability of HB parameters (quantified by the coefficient of variation COV and scale of fluctuation θ) and PF. Its effectiveness in assessing the impact of FS sensitivity on slope stability is also studied. A series of parametric studies are implemented. It is found that there is a strong relationship between FS sensitivity and PF: for slope cases with identical FS and the same COV of input HB parameters, a slope of higher FS sensitivity has a higher PF, indicating a higher risk. The relative contributions of the variability of HB parameters to PF are also compared. It is found that when the COV of GSI, mi, and σci are identical, the variability of GSI makes the largest contribution; however, when these COV are set to their upper-limit values observed in engineering practice, the high variability of σci makes the largest contribution. Finally, the investigation demonstrates that spatial variability of HB parameters (applicable to mi and σci in this study) has significant influences on slope… Advisors/Committee Members: Xu, Chaoshui (advisor), Karakus, Murat (advisor), Jaksa, Mark Brian (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: rock slope; Hoek-Brown strength criterion; probabilistic analysis; sensitivity analysis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Qian, Q. (2013). Relationship between input and output : a systematic study of the stability of highly fractured rock slopes using the Hoek-Brown strength criterion. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/82544

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Qian, Qian. “Relationship between input and output : a systematic study of the stability of highly fractured rock slopes using the Hoek-Brown strength criterion.” 2013. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/82544.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Qian, Qian. “Relationship between input and output : a systematic study of the stability of highly fractured rock slopes using the Hoek-Brown strength criterion.” 2013. Web. 19 Feb 2020.

Vancouver:

Qian Q. Relationship between input and output : a systematic study of the stability of highly fractured rock slopes using the Hoek-Brown strength criterion. [Internet] [Thesis]. University of Adelaide; 2013. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/82544.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Qian Q. Relationship between input and output : a systematic study of the stability of highly fractured rock slopes using the Hoek-Brown strength criterion. [Thesis]. University of Adelaide; 2013. Available from: http://hdl.handle.net/2440/82544

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

20. Shen, Jiayi. Analytical and numerical analyses for rock slope stability using the generalized Hoek-Brown criterion.

Degree: 2013, University of Adelaide

URL: http://hdl.handle.net/2440/83113

► Design of rock slope is one of the major challenges at every stage of open pit mining operations. Providing an optimal excavation design based on… (more)

▼ Design of rock slope is one of the major challenges at every stage of open pit mining operations. Providing an optimal excavation design based on a robust analysis in terms of safety, ore recovery and profit is the ultimate goal of any slope design. The rock slope stability is predominantly controlled by the strength and deformation of the rock mass which characteristically consists of intact rock materials and discontinuities. Initially, movement of the slope occurs due to stress relaxation as a result of removal of rocks which used to provide confinement. This behavior of slope can be attributed to linear elastic deformation. In addition to this, sliding along discontinuity surfaces and dilation in consequence of formation of cracks can occur. Ultimately all these instabilities lead to failure of the slopes. Therefore, formulation of slope designs plays critical role in the process of slope stability. In conventional approaches for assessing the stability of a homogeneous slope, such as the limit equilibrium method (LEM) and shear strength reduction (SSR) method, rock mass strength is usually expressed by the linear Mohr-Coulomb (MC) criterion. However, rock mass strength is a non-linear stress function. Therefore, the linear MC criterion generally do not agree with the rock mass failure envelope, especially for slope stability problems where the rock mass is in a state of low confining stresses that make the nonlinearity more dominant. With the aim of better understanding the fundamental rock slope failure mechanisms and improving the accuracy of the rock slope stability results, this research focuses on the application of the Hoek-Brown (HB) criterion, which can ideally represent the non-linear behavior of a rock mass, on the rock slope stability analysis. There, three major sections are available in the thesis. The first section, from Chapters 1 to 4, proposes new methods for estimating the intact rock and rock mass properties, which will be used for slope stability analysis. In the second section studied in Chapter 5, a new non-linear shear strength reduction technique is proposed for the analysis of three-dimensional (3D) slope modeling. In section three (Chapter 6), novel stability charts are proposed, which have the merit of estimating factor of safety (FOS) for a given slope directly from the HB parameters and rock mass properties. These charts can provide a quick and reliable assessment of rock slope stability. The major research contributions and outcomes of the overall researches are presented in six journal publications which are forming the thesis. The titles of Chapters 1 through 6 reflect the titles of the journal papers. In Chapter 1, laboratory tests conducted on Hawkesbury sandstone obtained from New South Wales are carried out to investigate the relationship between the HB constant mi and uniaxial compressive strength (UCS) of intact rock. Based on the analysis of the laboratory tests and the existing database, a new method that can estimate the HB constant mi values from UCS and rock types is… Advisors/Committee Members: Karakus, Murat (advisor), Xu, Chaoshui (advisor), Priest, Stephen Donald (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: generalized Hoek-Brown criterion; Hoek-Brown; rock slope; numerical analysis; analytical analysis

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Shen, J. (2013). Analytical and numerical analyses for rock slope stability using the generalized Hoek-Brown criterion. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/83113

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Shen, Jiayi. “Analytical and numerical analyses for rock slope stability using the generalized Hoek-Brown criterion.” 2013. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/83113.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Shen, Jiayi. “Analytical and numerical analyses for rock slope stability using the generalized Hoek-Brown criterion.” 2013. Web. 19 Feb 2020.

Vancouver:

Shen J. Analytical and numerical analyses for rock slope stability using the generalized Hoek-Brown criterion. [Internet] [Thesis]. University of Adelaide; 2013. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/83113.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Shen J. Analytical and numerical analyses for rock slope stability using the generalized Hoek-Brown criterion. [Thesis]. University of Adelaide; 2013. Available from: http://hdl.handle.net/2440/83113

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

21. Kashyap, Jaya. Out-of-plane strengthening of unreinforced masonry walls using FRP.

Degree: 2014, University of Adelaide

URL: http://hdl.handle.net/2440/84731

► Unreinforced masonry (URM) structures constitute both a significant portion of the world’s heritage buildings and a significant component of the modern residential building stock, and… (more)

▼ Unreinforced masonry (URM) structures constitute both a significant portion of the world’s heritage buildings and a significant component of the modern residential building stock, and are particularly susceptible to damage from out-of-plane loads such as those generated by earthquakes (Ingham and Griffith 2011). Consequently, there is a considerable need for the development of economical and effective seismic strengthening techniques for URM construction. This study investigates the performance of near surface mounted (NSM) carbon fibre reinforced polymer (CFRP) strengthened clay brick masonry walls under monotonic and cyclic out-of-plane bending with particular attention to the FRP-to-masonry joint behaviour. Fourteen NSM carbon FRP-to-masonry pull tests were conducted to study the FRP-to-masonry bond behaviour and to investigate the effect that variables such as cyclic loading and FRP strip dimensions have on the debonding resistance of a NSM FRP-to-masonry joint. The pull tests results were then incorporated into a large database of FRP retrofitted masonry pull test results by various researchers over the past 10 years. An empirical model was derived for the intermediate crack (IC) debonding resistance of FRP-to-masonry joints using a large set of test data from the open literature (Kashyap et al. 2012). Further, in order to predict the global load-slip response of FRP-to-masonry pull tests using various local bond-slip relationships two analytical procedures, namely a new generic numerical procedure and a closed-form mathematical solution, were developed which account for the partial-interaction response at the FRP-masonry interface (Kashyap et al. 2011). Fifteen walls were tested in this study to investigate the behaviour of NSM CFRP retrofitted masonry walls under out-of-plane bending and investigate the IC debonding failure mechanism in them. Also, the effects of typical design variables such as reverse cyclic loading, axial pre-compression, FRP strip spacing and reinforcement ratio on the stiffness, displacement capacity and ultimate strength of FRP retrofitted masonry walls were studied. The test results demonstrated that NSM CFRP strips designed to fail by IC debonding can provide an increase in strength of up to 20 times the strength of the corresponding unreinforced wall highlighting the effectiveness of the retrofitting scheme used. With respect to the test variables under investigation it was found that FRP strip spacing and reinforcement ratio strongly affect wall performance whereas cyclic loading and vertical pre-compression had little effect. Finally, a simple design methodology has been developed for masonry walls retrofitted with vertical CFRP strips with IC debonding as the preferred failure mechanism. This design methodology will provide solutions for choosing the FRP strip dimensions (bρ and tρ) and spacing (S). Importantly, the methodology is generic in the sense that it can be used for any type of FRP material and both externally bonded (EB) and NSM retrofit techniques. It also enables the… Advisors/Committee Members: Griffith, Michael Craig (advisor), Mohamed Ali, M. S. (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: brick masonry; earthquake; FRP; flexure; IC debonding; bond tests; bond-slip

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Kashyap, J. (2014). Out-of-plane strengthening of unreinforced masonry walls using FRP. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/84731

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Kashyap, Jaya. “Out-of-plane strengthening of unreinforced masonry walls using FRP.” 2014. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/84731.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Kashyap, Jaya. “Out-of-plane strengthening of unreinforced masonry walls using FRP.” 2014. Web. 19 Feb 2020.

Vancouver:

Kashyap J. Out-of-plane strengthening of unreinforced masonry walls using FRP. [Internet] [Thesis]. University of Adelaide; 2014. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/84731.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Kashyap J. Out-of-plane strengthening of unreinforced masonry walls using FRP. [Thesis]. University of Adelaide; 2014. Available from: http://hdl.handle.net/2440/84731

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

22. Zhang, Fangrui. Dynamic analysis of steel confined concrete tubular columns against blast loads.

Degree: 2017, University of Adelaide

URL: http://hdl.handle.net/2440/104727

► The use of composite construction has drawn more and more attention in recent decades. This thesis contains a number of journal articles which aim to… (more)

▼ The use of composite construction has drawn more and more attention in recent decades. This thesis contains a number of journal articles which aim to enrich the knowledge of the performance of concrete filled tubular columns when subjected to blast loading. Experimental investigations are used in conjunction with numerical analysis to provide a thorough assessment of the blast-resistance of concrete filled tubular columns. The first chapter mainly focuses on the experimental study on concrete filled tubular columns under blast loading. A large-scale blast experimental program is carried out on concrete filled double-skin steel tube (CFDST) columns. The blast experiment aims to examine the blast-resistance of ten CFDST specimens, including five with square cross-section and the other five with circular cross-section. The parameters that are investigated during the blast experiment include: cross-sectional geometry, explosive charge weight and magnitude of axial load. After the experiment, several damaged test specimens are then transported back to the laboratory for residual axial load-carrying capacity tests. The proposed CFDST columns are able to retain more than 60% of its axial load-carrying capacity even after being subjected to close-range explosion. As blast experiments are often costly and associated with potential safety concerns, numerical tools have been adopted by more and more researchers. In the second chapter of the thesis, numerical approaches in modelling the dynamic behaviour of concrete filled steel tube (CFST) columns and CFDST columns under blast loading are presented. The numerical models are validated against the results of the blast experiment as described in the first chapter and good agreement is achieved. Parametric studies on the effect of column dimensions and material properties are also discussed through intensive numerical simulations. In the last chapter, a numerical method to generate pressure-impulse diagrams for CFDST columns is proposed which uses a damage criterion involving the residual axial load-carrying capacity. Based on the numerical method, pressure-impulse diagrams for different column configurations are derived and analytical expressions of deriving pressure-impulse diagrams for CFDST columns are also developed through regression analysis. Advisors/Committee Members: Bennet, Terry (advisor), Zhao, Xiao-Ling (advisor), Wu, Chengqing (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: CFDST; UHPC; blast loading; Research by Publication

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APA (6^th Edition):

Zhang, F. (2017). Dynamic analysis of steel confined concrete tubular columns against blast loads. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/104727

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Zhang, Fangrui. “Dynamic analysis of steel confined concrete tubular columns against blast loads.” 2017. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/104727.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Zhang, Fangrui. “Dynamic analysis of steel confined concrete tubular columns against blast loads.” 2017. Web. 19 Feb 2020.

Vancouver:

Zhang F. Dynamic analysis of steel confined concrete tubular columns against blast loads. [Internet] [Thesis]. University of Adelaide; 2017. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/104727.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Zhang F. Dynamic analysis of steel confined concrete tubular columns against blast loads. [Thesis]. University of Adelaide; 2017. Available from: http://hdl.handle.net/2440/104727

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

23. Salt, Melissa R. Water balance and the influence of temporal factors on final covers for landfill closure.

Degree: 2013, University of Adelaide

URL: http://hdl.handle.net/2440/92333

► Final covers for landfill have consisted of engineered barriers to prevent contact with the underlying waste, limit the generation of leachate and emission of landfill… (more)

▼ Final covers for landfill have consisted of engineered barriers to prevent contact with the underlying waste, limit the generation of leachate and emission of landfill gas. The theory for cover design has predominantly relied on attempting to prevent moisture from draining into the waste by placing an impermeable or low conductivity barrier, often as compacted clay or more recently as geotextile or geocomposite layers (GCL). However, studies overseas over the last 10 – 15 years have shown that these barrier layers, particularly compacted clay barriers, may not perform as expected. Increasingly, interest has been focussed on designing covers that maximise evapotranspiration as this release to the atmosphere does not have other detrimental implications. In 2006, the Waste Management Association of Australia and the Australian Research Council co-funded collaborative research between 5 Australian Universities to research the performance of compacted clay barriers and the emerging technology of phytocaps (also known as ET (evapotranspiration), alternate or store-and-release covers). This PhD is part of this collaborative research and aimed to: quantify drainage from phytocaps and conventional caps; compare water balance performance of conventional caps, including a compacted clay barrier, and phytocaps under a range of climatic, soil and vegetation conditions; and assess the temporal changes in the covers. The trial methodology was based on field-scale lysimetry with phytocaps trialled in 5 Australian States. All test sections were constructed on previously landfilled cells and included a 10 m x 20 m lysimeter instrumented to measure weather, runoff, lateral flow (compacted clay sections only), drainage and soil moisture content. An adjacent control section without a liner to bound the area was also instrumented to provide an assessment of the impact of the lysimeter liner on the water balance. At 3 trial sites, the research included side-by-side comparison of a conventional compacted clay barrier cap and a phytocap. Data collection at the sites has been undertaken for 3 – 4 years. The climate at the trial sites varies from summer-dominant rainfall in a tropical climate to sub-tropical and temperate climates with all-year rainfall and to temperate climates with hot, dry summers. The soil varied from alluvial loam and basaltic-derived clayey loam to coarse loamy sand. At one site, municipal waste compost was added to the available sandy loam. The vegetation has also varied between the sites from dominantly tree-based vegetation to only native grasses. The research has found that phytocaps have the potential to reduce drainage to the same extent as conventional caps. Also, the short term data collected indicate that phytocaps are likely to be more sustainable in the longer term as the changes in the soil moisture content range over the trial timeframe tended to be beneficial in the phytocap, with increased soil storage as the plant roots developed, and detrimental in the conventional cap, with cracking and preferential… Advisors/Committee Members: Jaksa, Mark Brian (advisor), Cox, Jim (advisor), Lightbody, Paul (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: landfill; phytocap; compacted clay barrier; A-ACAP; Australia; lysimeter; closure; post-closure

…of Adelaide, CSIRO Division of Land and Water and The University of Western Australia. The… …Australia, Griffith University, Central Queensland University, Murdoch University, The University…

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APA (6^th Edition):

Salt, M. R. (2013). Water balance and the influence of temporal factors on final covers for landfill closure. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/92333

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Salt, Melissa R. “Water balance and the influence of temporal factors on final covers for landfill closure.” 2013. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/92333.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Salt, Melissa R. “Water balance and the influence of temporal factors on final covers for landfill closure.” 2013. Web. 19 Feb 2020.

Vancouver:

Salt MR. Water balance and the influence of temporal factors on final covers for landfill closure. [Internet] [Thesis]. University of Adelaide; 2013. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/92333.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Salt MR. Water balance and the influence of temporal factors on final covers for landfill closure. [Thesis]. University of Adelaide; 2013. Available from: http://hdl.handle.net/2440/92333

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

24. Soltani, Amin. Mechanical behavior of tire rubber–reinforced expansive soils.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/118009

► Expansive soils are amongst the most significant, widespread, costly, and least publicized geologic hazards. Where exposed to seasonal environments, such soils exhibit significant volume changes… (more)

▼ Expansive soils are amongst the most significant, widespread, costly, and least publicized geologic hazards. Where exposed to seasonal environments, such soils exhibit significant volume changes as well as desiccation–induced cracking, thereby bringing forth instability concerns to the overlying structures and hence incurring large amounts of maintenance costs. Consequently, expansive soils demand engineering solutions to alleviate the associated socio–economic impacts on human life. Common solutions to counteract the adversities associated with problematic soils include soil replacement and/or soil stabilization. The latter refers to any chemical, mechanical or combined chemical–mechanical practice of altering the soil fabric to meet the intended engineering criteria. Though proven effective, conventional stabilization schemes often suffer from sustainability issues related to high manufacturing and/or transportation costs, and environmental concerns due to greenhouse gas emissions. The transition towards sustainable stabilization necessitates reusing solid wastes and/or industrial by–products as part of the infrastructure system, and more specifically as replacements for conventional stabilization agents such as cement, lime, geogrids and synthetic fibers. Among others, discarded tires constitute for one of the largest volumes of disposals throughout the world, and as such, demand further attention. Given the high–volume generation (and disposal) of waste tire rubbers every year throughout the world, a major concern hitherto has been the space required for storing and transporting such waste materials, and the resulting health hazards and costs. Those characteristics which make waste tire rubbers such a problem while being landfilled, make them one of the most reusable waste materials for engineering applications such as soil stabilization, as the rubber is resilient, lightweight and skin–resistive. Beneficial reuse of recycled tire rubbers for stabilization of expansive soils would not only address the geotechnical–related issue, but would also encourage recycling, mitigate the burden on the environment and assist with waste management. The present study intends to examine the rubber’s capacity of ameliorating the inferior engineering characteristics of expansive soils, thereby solving two widespread hazards with one solution. Two rubber types of fine and coarse categories, i.e. rubber crumbs/powder and rubber buffings, were each examined at various rubber contents (by weight). The experimental program consisted of consistency limits, standard Proctor compaction, oedometer swell– shrink/consolidation, soil reactivity (or shrink–swell index), cyclic wetting–drying, cracking intensity, unconfined compression (UC), split tensile (ST), direct shear (DS) and scanning electron microscopy (SEM) tests. Improvement in the swell–shrink/consolidation capacity, cracking intensity and shear strength (DS test) were all in favor of both a higher rubber content and a larger rubber size. However, rubber contents greater than 10%… Advisors/Committee Members: Deng, An (advisor), Taheri, Abbas (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Expansive soil; waste tire rubber; swell-shrink/consolidation; cracking intensity; shear strength; dimensional analysis; polyacrylamide

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Soltani, A. (2018). Mechanical behavior of tire rubber–reinforced expansive soils. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/118009

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Soltani, Amin. “Mechanical behavior of tire rubber–reinforced expansive soils.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/118009.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Soltani, Amin. “Mechanical behavior of tire rubber–reinforced expansive soils.” 2018. Web. 19 Feb 2020.

Vancouver:

Soltani A. Mechanical behavior of tire rubber–reinforced expansive soils. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/118009.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Soltani A. Mechanical behavior of tire rubber–reinforced expansive soils. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/118009

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

25. Wang, Can. Numerical modelling of tyre-derived geo-composites.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/118067

► This thesis aims to study the property of rubber–sand mixtures as a geotechnical alternative. Previous studies have shown superior properties of this artificial composite such… (more)

▼ This thesis aims to study the property of rubber–sand mixtures as a geotechnical alternative. Previous studies have shown superior properties of this artificial composite such as high resiliency, light weight, and improved skin-resistance. Also, when mixed with conventional geotechnical materials, the composite often exhibits adjusted void ratio, high compressibility, high compression, high friction angle, and high attenuation of vibration. In the past, the major efforts were focused on the laboratory tests. There is limited research in numerical domain performed to predict the mechanical behaviour of rubber–soil. In these numerical studies, approximations are unsatisfactory because the past studies usually treat the compressible rubble granule as a rigid material. To address these research gaps, this study in this thesis develops and applies a series of numerical models to replicate the compressible nature of the rubber material and to examine the behaviour of the rubber-derived composite materials. The behaviour includes the shear strength, dynamic damping, mixture segregation, contact asperity, and contact deformation, from the macro-to microscale. The aims of this thesis contain the following aspects: 1) investigating the shear strength of rubber–sand mixture obtained in direct shear test; 2) assessing the segregation occurred when rubber–sand mixture is placed; 3) developing a coupled numerical method to replicate rigid–soft matters interaction; and 4) examining the influence of material surface asperity on energy dissipation. To attain these aims, the discrete element method (DEM), a numerical modelling tool, is employed to develop a series of modelling framework. The framework is validated, verified and applied through a blend of solutions, including test setups, analytical solutions, example problems and case studies. The DEM is used to replicate the discrete natural of rubber granules. Using this method, the macroscopic material response and particle flow can be monitored by determining granular properties such as contact stiffness, friction and damping coefficient. As a significant numerical tool, the commercial software package PFC is used to investigate the rubber and soil granular interactions. Advisors/Committee Members: Deng, An (advisor), Taheri, Abbas (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Numerical; tyre; composites; DEM; discrete element; digital image; segregation; surface friction; roughness; EFG; element free; Galerkin; coupling; meshless

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APA (6^th Edition):

Wang, C. (2018). Numerical modelling of tyre-derived geo-composites. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/118067

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Wang, Can. “Numerical modelling of tyre-derived geo-composites.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/118067.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Wang, Can. “Numerical modelling of tyre-derived geo-composites.” 2018. Web. 19 Feb 2020.

Vancouver:

Wang C. Numerical modelling of tyre-derived geo-composites. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/118067.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Wang C. Numerical modelling of tyre-derived geo-composites. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/118067

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

26. Gu, Lei. Degradation phenomenon of cementitious materials under sulphuric acid attack.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/118115

► Sulphuric acid corrosion of Ordinary Portland Cement (OPC) based materials has attracted significant attention in recent decades, both as a result of its widespread occurrence… (more)

▼ Sulphuric acid corrosion of Ordinary Portland Cement (OPC) based materials has attracted significant attention in recent decades, both as a result of its widespread occurrence in aggressive environments and the substantial economic impact of the resulting damage. At the same time, the development of alkali-activated (AA) cementitious materials that have been reported to have considerably improved durability-related properties has significantly increased. Alkali-activated cementitious materials are expected to have higher sulphuric acid resistance than that of OPC based materials and investigations on understanding the behaviour of OPC based and AA cementitious materials under sulphuric attack therefore of great research interest. The agglomeration of a global database of test results is complicated by the differing test methodologies employed in each study which makes it very difficult to compare the relative results of studies performed as part of septate experimental campaigns. To better utilise the results of existing and new experimental studies and to be able to compare the results across different types of material there is a need to assess and understand the results obtained from a range of test methodologies applies to for a range of cementitious composite materials. This thesis contains a series of journal papers in which the methodologies commonly applied in the literature have been further assessed and the degradation mechanisms under sulphuric acid attack of both OPC based and AA cementitious materials at the paste, mortar, and concrete levels have been investigated. In the assessment of test methodologies of OPC and AA concrete under sulphuric acid attack, the behaviour of concretes with different exposure regimes (continuous immersion, brushing, and wetting and drying cycling) and chemical concentrations (1% and 3% w/w) have been investigated such that the influence of test methodology on degradation rate and microstructural performance can be identified. The results show that the OPC and AA concrete subjected to increased acid concentration displays the most rapid degradation. The indicators of susceptibility to corrosion (acid consumption, change of mass, length, compressive strength, and cross-section) are also discussed based on their potential advantages and limitations as well as application to both OPC based and AA cementitious materials. The results show that there is no single universal indicator of resistance to sulphuric acid that could be applied as a simple test technique for both materials. Through these assessments of the test methods and measurement technique, it shows that a test procedure to indicate the susceptibility of concretes can be performed within a reasonable time frame for standard testing. In the investigation of degradation mechanism of OPC based and AA cementitious materials under sulphuric acid attack, the physical, mechanical properties, and the chemical and microstructural characteristics of cementitious materials have been analysed over time. A multiscale approach has… Advisors/Committee Members: Bennett, Terry (advisor), Visintin, Phillip (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Concrete degradation; sulphuric acid corrosion; microstructure; alkali-activated concrete; assessment of test methodologies

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Gu, L. (2018). Degradation phenomenon of cementitious materials under sulphuric acid attack. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/118115

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Gu, Lei. “Degradation phenomenon of cementitious materials under sulphuric acid attack.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/118115.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Gu, Lei. “Degradation phenomenon of cementitious materials under sulphuric acid attack.” 2018. Web. 19 Feb 2020.

Vancouver:

Gu L. Degradation phenomenon of cementitious materials under sulphuric acid attack. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/118115.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Gu L. Degradation phenomenon of cementitious materials under sulphuric acid attack. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/118115

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

27. Khatami, Hamidreza. A study of arching effect in soils incorporating receycled tyres.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/118117

► The term ‘arching effect’ refers to the phenomenon of stress redistribution in granular materials because of induced differential displacements and/or significant stiffness difference between the… (more)

▼ The term ‘arching effect’ refers to the phenomenon of stress redistribution in granular materials because of induced differential displacements and/or significant stiffness difference between the substituted and original materials. Arching is frequently observed in different geotechnical practice such as piled and geogrid-reinforced embankments, foundation piles, retaining walls, backfills, tunnelling, buried pipes, and excavation. Knowledge of arching mechanism serves to assist engineers in optimising their soil-structure design. Investigation of mechanical properties and potential applications of recycled-tyre-based aggregates has been carried out extensively over the last 25 years firstly to exploit the beneficial engineering properties of waste tyres such as their light weight as backfilling material and secondly to mitigate their environmental impact. However, to the author’s knowledge, no previous study of the arching effect in rubber-soil mixtures have been reported in literature at the time of this research. As rubberised soil is gradually establishing its place as a suitable and cost-effective alternative to natural aggregate in geotechnical work, it is worthwhile to have a thorough knowledge of the arching effect in rubber-soil mixtures. This thesis aims at experimentally investigating the arching effect in a coarse sand and rubber-soil mixtures using the Digital Image Correlation (DIC) technique and stress measurements. Active and passive arching modes in soil and rubberised soil were studied and compared. To do so, a replicate of Terzaghi’s original trapdoor apparatus was manufactured and filled with dyed sand and 10% and 30% (by weight) rubberised sand. Imaging and DIC analysis of the arching effect induced deformation in the trapdoor apparatus for the aforementioned granular material were conducted using VicSnap and VIC-2D computer programs. The distribution regimes of vertical and horizontal displacements and strains in the specimen cross-sectional area were obtained and interpreted. Additionally, shear strains, major and minor principal strains, and volumetric strains were computed and analysed. The effect of a central 5 kPa surcharge on these variables was also studied. It was observed that the DIC technique provides small-scale information and insights into how and where the arching effect creates zones of different local deformations within soil. The patterns and values of these deformation fields were found to be dependent on the test conditions and material type. As part of the experimental plan, the evolution of stresses over the trapdoor element and its adjacent, static bases, was recorded during the experiments using a number of stress sensors. Advisors/Committee Members: Deng, An (advisor), Jaksa, Mark (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Arching effect; rubber-sand; digital image correlation; stress; deformation

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Khatami, H. (2018). A study of arching effect in soils incorporating receycled tyres. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/118117

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Khatami, Hamidreza. “A study of arching effect in soils incorporating receycled tyres.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/118117.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Khatami, Hamidreza. “A study of arching effect in soils incorporating receycled tyres.” 2018. Web. 19 Feb 2020.

Vancouver:

Khatami H. A study of arching effect in soils incorporating receycled tyres. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/118117.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Khatami H. A study of arching effect in soils incorporating receycled tyres. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/118117

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

28. Le, Phuong Dong. A new flood estimation paradigm for the design of civil infrastructure systems.

Degree: 2018, University of Adelaide

URL: http://hdl.handle.net/2440/118134

► Methods for quantifying flood risk of civil infrastructure systems such as road and rail networks require considerably more information compared to traditional methods that focus… (more)

▼ Methods for quantifying flood risk of civil infrastructure systems such as road and rail networks require considerably more information compared to traditional methods that focus on flood risk at a point. These systems are characterised by multiple interconnected components, whereby a ‘failure’ of the overall system can arise because of complex combinations of failures in system subcomponents. For example, flooding of a single bridge along a railway may leave the entire railway inoperable, and the interest is often in the probability that one or more bridges along a stretch of railway will be flooded, rather than designing each bridge in isolation. Similarly, the viability of evacuation routes often requires an assessment of the probability that the route is flooded, conditional on an evacuation being necessary as a result of floods elsewhere in the system. Conventional design flood estimation processes are ill-equipped to deal with these complex problems. Whereas traditional flood estimation approaches focus on estimating flood risk at a single location, this thesis proposes a new estimation paradigm that focuses on estimating system-wide risk. The approach builds on the traditional intensity-duration-frequency (IDF) methods that are commonly used in engineering practice in Australia and internationally; however, this is implemented in such a way at to provide information on the spatial dependence of design storms. A particular innovation in this thesis is to estimate spatial rainfall dependence across multiple storm durations, allowing it to be used to estimate flood risk across multiple catchments with differing times of concentration. This enables the estimation of both conditional probabilities (e.g. probability of one part of a system being flooded conditional on another part of the system being flooded) and joint probabilities (e.g. the probability of multiple parts of a system experiencing floods simultaneously). Finally, whereas traditional IDF approaches consider conversion from point rainfall to spatial rainfall via areal reduction factors as a post-processing step, the approach proposed herein enables this conversion implicitly as part of the method. The proposed approach is based on two classes of extreme value model: max-stable process models, and inverted max-stable process models. These models differ in their assumption for how spatial dependence scales in the limit, as the rainfall events become increasingly extreme (referred to as “asymptotic dependence”). In particular, max-stable models assume asymptotic dependence (i.e. the spatial dependence converges to a non-zero limit), whereas inverted max-stable models assume asymptotic independence. This assumption has significant implications for very rare events (e.g. the 1% annual exceedance probability event), particularly when the estimates are based on relatively short observational records. Specifically, implementation focuses on the (inverted) Brown-Resnick family of models. This class of model was adjusted by accounting for spatial dependence… Advisors/Committee Members: Westra, Seth (advisor), Leonard, Michael (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: Asymptotic independence; conditional probability; extreme rainfall; inverted max-stable process; joint probability

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APA (6^th Edition):

Le, P. D. (2018). A new flood estimation paradigm for the design of civil infrastructure systems. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/118134

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Le, Phuong Dong. “A new flood estimation paradigm for the design of civil infrastructure systems.” 2018. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/118134.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Le, Phuong Dong. “A new flood estimation paradigm for the design of civil infrastructure systems.” 2018. Web. 19 Feb 2020.

Vancouver:

Le PD. A new flood estimation paradigm for the design of civil infrastructure systems. [Internet] [Thesis]. University of Adelaide; 2018. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/118134.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Le PD. A new flood estimation paradigm for the design of civil infrastructure systems. [Thesis]. University of Adelaide; 2018. Available from: http://hdl.handle.net/2440/118134

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

29. Nguyen, Duc Cong Hiep. Optimal water allocation and scheduling for irrigation using ant colony algorithms.

Degree: 2016, University of Adelaide

URL: http://hdl.handle.net/2440/113356

► In most regions of the world, irrigation is vital for food production. However, under increased water demands due to population growth, economic development, and climate… (more)

▼ In most regions of the world, irrigation is vital for food production. However, under increased water demands due to population growth, economic development, and climate change in recent decades, there is likely to be a significant reduction in the amount of water available for irrigation. Therefore, it is imperative to make the best use of water that is available for irrigation. This applies to: 1) the optimal allocation of land and water resources for irrigation management to achieve maximum net return, subject to constraints on area and water allocations at the district or regional scale; and 2) the optimal irrigation scheduling of available water, as well as fertilizer, in order to maximise net return at the farm scale. In order to rigorously address these problems, metaheuristic optimization algorithms have been used extensively due to their abilities in terms of finding globally optimal or near-globally optimal solutions and relative ease of linkage with complex simulation models. However, the application of these algorithms to real-world problems has been challenging due to the generally large size of the search space and the computational effort associated with realistic long-term simulation of crop growth and associated soil-water processes. In this thesis, general simulation-optimization frameworks for optimal irrigation management (including optimal crop and water allocation, and optimal irrigation water and fertilizer application scheduling) have been developed in order to make the application of metaheuristic optimization methods to the above problems more computationally efficient. As part of this approach the problems are represented in the form of decision graphs which are solved using ant colony optimization (ACO) as the optimization engine. The frameworks enable dynamic reduction of the size of the search space by using dynamic decision variable option (DDVO) adjustment during solution construction. This also ensures only feasible solutions are obtained as part of the stepwise solution generation process. In addition, the computational efficiency of the ACO algorithms within the framework for optimal crop and water allocation has been increased by biasing the options at each node in the decision-tree graph based on domain knowledge (represented by a visibility factor, VF). Furthermore, the framework for optimal irrigation scheduling was linked with a process-based crop growth model to enable optimal or near-optimal irrigation water and fertilizer application schedules to be identified. This thesis is arranged as a series of three publications that present the main research contributions. The first paper introduces a generic simulation-optimization framework for optimal crop and water allocation at the regional or district scale using decision-tree graphs, ACO and the search space reduction technique based on dynamically adjusting decision variable options during stepwise solution construction. The performance of this technique in terms of finding feasible solutions, solution quality, computational… Advisors/Committee Members: Maier, Holger R. (advisor), Dandy, Graeme Clyde (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: optimization; irrigation scheduling; water allocation; cropping patterns; ant colony optimization; crop growth modeling; Research by Publication

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APA (6^th Edition):

Nguyen, D. C. H. (2016). Optimal water allocation and scheduling for irrigation using ant colony algorithms. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/113356

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Nguyen, Duc Cong Hiep. “Optimal water allocation and scheduling for irrigation using ant colony algorithms.” 2016. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/113356.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Nguyen, Duc Cong Hiep. “Optimal water allocation and scheduling for irrigation using ant colony algorithms.” 2016. Web. 19 Feb 2020.

Vancouver:

Nguyen DCH. Optimal water allocation and scheduling for irrigation using ant colony algorithms. [Internet] [Thesis]. University of Adelaide; 2016. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/113356.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Nguyen DCH. Optimal water allocation and scheduling for irrigation using ant colony algorithms. [Thesis]. University of Adelaide; 2016. Available from: http://hdl.handle.net/2440/113356

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

University of Adelaide

30. Perez Ospina, Santiago. Acoustic analysis of rock cutting process for impregnated diamond drilling.

Degree: 2016, University of Adelaide

URL: http://hdl.handle.net/2440/113357

► The rock cutting industry has experienced important changes with the introduction of diamond-based drilling tools in the last few decades. Impregnated diamond (ID) bits are… (more)

▼ The rock cutting industry has experienced important changes with the introduction of diamond-based drilling tools in the last few decades. Impregnated diamond (ID) bits are part of that introduction and their main use is to drill hard and abrasive rock formations. ID core drilling has emerged as the most commonly used technology employed in the advanced stages of mineral exploration. Through this technology, existing resources - mineral and energy - are expanded and greenfield exploration is carried out. As near-surface deposits are depleted, there is a global trend towards targeting deeper for exploration. Currently, in near-surface drilling, bit wear condition is determined by the experience of drilling operators –trial and error–. Although it makes the evaluation very subjective and prone to errors, it is an accepted practice. Conversely, in deep drilling, direct assessment of the bit wear condition is difficult and time consuming. Therefore, alternative techniques must be developed in order to evaluate, in real time, the wear condition of the bit and properties of the drilling medium. In this thesis, Acoustic Emission (AE) along with Measuring While Drilling (MWD) parameters are considered as an alternative technique to remotely monitor the ID bit wear condition (sharp and blunt) and rock properties (abrasivity). A series of rigorous and specialized drilling and abrasivity tests are utilised to generate the acoustic signatures with (topologically variant) and without (topologically invariant) changes in the topology of the tool cutting face. Main findings of this work are as follows: firstly, based on the step test results, linear relationships were developed that make it possible to estimate the depth of cut, weight on the bit (WOB) and torque on the bit (TOB) by simply using the time domain parameters of the AE signals. Wear tests also showed that AE amplitudes start to trend down as wear begins to accelerate. Secondly, acceptable pattern recognition rates are obtained for the majority of tool condition monitoring systems developed for predicting sharpness or bluntness of ID bits. In particular, the system composed by AErms [rms subscript] and TOB excels due to the high classification performance rates and the fewer input variables compared to other tool condition monitoring systems. Lastly, AE parameters, such as total number of events and root mean square of AE, in addition to testing parameters are found to accurately predict rock abrasivity measured via Cerchar Abrasivity Index (CAI). The importance of this index lies on: (i) the fact that ID drilling is commonly used in abrasive rock formations, and (ii) the way CAI has been defined (length of wear flat exerted on a steel pin after being scratched on one centimetre of rock surface), which intrinsically relates it to wear condition of the tool. The insights presented in this thesis open up a new promising field of study, impregnated diamond drilling using AE as an indirect technique to evaluate tool condition. Advisors/Committee Members: Karakus, Murat (advisor), Xu, Chaoshui (advisor), School of Civil, Environmental and Mining Engineering (school).

Subjects/Keywords: acoustic emission; diamond drilling; bit wear; rock abrasivity; machine learning; Research by Publication

Record Details Similar Records Cite « Share

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6^th Edition):

Perez Ospina, S. (2016). Acoustic analysis of rock cutting process for impregnated diamond drilling. (Thesis). University of Adelaide. Retrieved from http://hdl.handle.net/2440/113357

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16^th Edition):

Perez Ospina, Santiago. “Acoustic analysis of rock cutting process for impregnated diamond drilling.” 2016. Thesis, University of Adelaide. Accessed February 19, 2020. http://hdl.handle.net/2440/113357.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7^th Edition):

Perez Ospina, Santiago. “Acoustic analysis of rock cutting process for impregnated diamond drilling.” 2016. Web. 19 Feb 2020.

Vancouver:

Perez Ospina S. Acoustic analysis of rock cutting process for impregnated diamond drilling. [Internet] [Thesis]. University of Adelaide; 2016. [cited 2020 Feb 19]. Available from: http://hdl.handle.net/2440/113357.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Perez Ospina S. Acoustic analysis of rock cutting process for impregnated diamond drilling. [Thesis]. University of Adelaide; 2016. Available from: http://hdl.handle.net/2440/113357

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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Open Access Theses and Dissertations