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Faculty of Engineering - Papers (Archive)

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Full-Text Articles in Engineering

Effects Of Membrane Fouling On N-Nitrosamine Rejection By Nanofiltration And Reverse Osmosis Membranes, Takahiro Fujioka, Stuart J. Khan, James A. Mcdonald, Rita K. Henderson, Yvan Poussade, Jorg E. Drewes, Long Nghiem Jan 2013

Effects Of Membrane Fouling On N-Nitrosamine Rejection By Nanofiltration And Reverse Osmosis Membranes, Takahiro Fujioka, Stuart J. Khan, James A. Mcdonald, Rita K. Henderson, Yvan Poussade, Jorg E. Drewes, Long Nghiem

Faculty of Engineering - Papers (Archive)

The impact of fouling on N-nitrosamine rejection by nanofiltration (NF) and reverse osmosis (RO) membranes was investigated in this study. Membrane fouling was simulated using tertiary treated effluent and several model fouling solutions (that contained sodium alginate, bovine serum albumin, humic acid or colloidal silica) to elucidate the changes in rejection behaviour of N-nitrosamines. In general, the rejection of N-nitrosamines increased when the membranes were fouled by tertiary effluent. The rejection of small molecular weight N-nitrosamines was most affected by membrane fouling. In particular, the rejection of N-nitrosodimethylamine (NDMA) by the ESPA2 membrane increased from 34 to 73% after membrane ...


Effect Of Ply Configuration On Hollow Square Reinforced Concrete Columns Confined With Carbon Fibre-Reinforced Polymer (Cfrp), T D. Le, M T. Lester, Muhammad N. S Hadi Jan 2013

Effect Of Ply Configuration On Hollow Square Reinforced Concrete Columns Confined With Carbon Fibre-Reinforced Polymer (Cfrp), T D. Le, M T. Lester, Muhammad N. S Hadi

Faculty of Engineering - Papers (Archive)

This paper presents results of testing twelve hollow square reinforced concrete specimens wrapped with Carbon fibre reinforced polymer CFRP. The effect of ply configuration on the behaviour of the specimens is investigated. All specimens were 800mm high and had the dimensions of 200mm×200mm in cross-section and a hollow core of 80mm×80 mm. The specimens were divided into four groups with three specimens each. The specimens in the first group without bonding CFRP served as references. While the remaining three groups of specimens were externally wrapped with CFRP in three different ply configurations of hoop, vertical and 45◦ angle ...


Effect Of Eccentric Load On Retrofitted Reinforced Concrete Columns Confined With Frp, Thong M. Pham, X Lei, Muhammad N. S Hadi Jan 2013

Effect Of Eccentric Load On Retrofitted Reinforced Concrete Columns Confined With Frp, Thong M. Pham, X Lei, Muhammad N. S Hadi

Faculty of Engineering - Papers (Archive)

Different behaviour of diverse sections of confined Reinforced Concrete (RC) columns under eccentric load is investigated in this study. Three types of sections are considered, which include square columns, square with rounded corners and modified circular columns. Twelve reinforced square concrete columns were made from normal strength concrete and subdivided into four groups. The first three columns were the Reference Group and had no modification.The next three columnswere modified with round corners and wrapped with three layers of Carbon Fibre Reinforced Polymer (CFRP), another three were bonded with four pieces of segmental circular concrete covers and wrapped with three ...


An Elasto-Plastic Model For Liquefiable Sands Subjected To Torsional Shear Loadings, Gabriele Chiaro, Junichi Koseki, Nalin L. I De Silva Jan 2013

An Elasto-Plastic Model For Liquefiable Sands Subjected To Torsional Shear Loadings, Gabriele Chiaro, Junichi Koseki, Nalin L. I De Silva

Faculty of Engineering - Papers (Archive)

This paper presents a modeling procedure for simulating the monotonic undrained torsional shear behavior of sands, including stress-strain relationship, and excess pore water pressure generation, while considering the void ratio and stress level dependence of stress-strain-dilatancy behavior of sand. A unique set of soil parameters is required by the model to satisfactorily predict the undrained behavior of loose and dense Toyoura sand over a wide range of initial void ratios and confining pressures, as proven by simulating experimental data produced by the authors and found in the literature.


Influence Of Ti/N Ratio On Simulated Cghaz Microstructure And Toughness In X70 Steels, Z X. Zhu, M Marimuthu, L Kuzmikova, H J. Li, F Barbaro, L Zheng, M Z. Bai, C Jones Jan 2013

Influence Of Ti/N Ratio On Simulated Cghaz Microstructure And Toughness In X70 Steels, Z X. Zhu, M Marimuthu, L Kuzmikova, H J. Li, F Barbaro, L Zheng, M Z. Bai, C Jones

Faculty of Engineering - Papers (Archive)

Three API 5L X70 steels with different Ti and N contents and otherwise identical chemistry were selected to investigate the effect of Ti/N ratio on the toughness in coarse grained heat affected zone (CGHAZ). A Gleeble 3500 thermomechanical simulator was used to simulate the thermal profile of CGHAZ of double submerged arc welding process. The microstructure was examined by optical microscopy. Statistics of CGHAZ grain coarsening were compiled by measuring the prior austenite grain size. Toughness of the simulated CGHAZ regions was evaluated by Charpy V-notch testing at -20 and -40°C. Morphology of the impact fracture surface was ...


Stabilization Of Nazn(Bh4)3 Via Nanoconfinement In Sba-15 Towards Enhanced Hydrogen Release, Guanglin Xia, Li Li, Zaiping Guo, Qinfen Gu, Yanhui Guo, Xuebin Yu, Hua-Kun Liu, Zongwen Liu Jan 2013

Stabilization Of Nazn(Bh4)3 Via Nanoconfinement In Sba-15 Towards Enhanced Hydrogen Release, Guanglin Xia, Li Li, Zaiping Guo, Qinfen Gu, Yanhui Guo, Xuebin Yu, Hua-Kun Liu, Zongwen Liu

Faculty of Engineering - Papers (Archive)

In the present work, the decomposition behaviour of NaZn(BH4)3 nanoconfined in mesoporous SBA-15 has been investigated in detail and compared to bulk NaZn(BH4)3 that was ball milled with SBA-15, but not nanoconfined. The successful incorporation of nanoconfined NaZn(BH4)3 into mesopores of SBA-15 was confirmed by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, 11B nuclear magnetic resonance, nitrogen absorption/desorption isotherms, and Fourier transform infrared spectroscopy measurements. It is demonstrated that the dehydrogenation of the space-confined NaZn(BH4)3 is free of emission of boric by-products, and significantly improved hydrogen release kinetics ...


Microstructure Evolution And Alloying Elements Distribution Between The Phases In Powder Near-B Titanium Alloys During Thermo-Mechanical Processing, Mansur Ahmed, Azdiar A. Gazder, Dmytro G. Savvakin, Orest M. Ivasishin, E V. Pereloma Jun 2012

Microstructure Evolution And Alloying Elements Distribution Between The Phases In Powder Near-B Titanium Alloys During Thermo-Mechanical Processing, Mansur Ahmed, Azdiar A. Gazder, Dmytro G. Savvakin, Orest M. Ivasishin, E V. Pereloma

Faculty of Engineering - Papers (Archive)

In the present study, two powders near-β Ti alloys having a nominal composition of Ti-5Al-5Mo-5V-XCr-1Fe (X = 1–2, wt%) were studied. The alloys were produced via the blended elemental powder metallurgy technique using hydrogenated Ti powder. Microstructure evolution and the distribution of the alloying elements between the phases were investigated after each step of thermo-mechanical processing (TMP). Microstructures were refined through the TMP in both alloys. Porosity was reduced with deformation at 1173 K (900 °C) in the β phase field. The β → α phase transformation occurred during soaking at 1023 K (750 °C) in the α + β phase field ...


Development Of Reliability-Based Design For Railway Prestressed Concrete Sleepers, Sakdirat Kaewunruen, Alexander Remennikov, Martin H. Murray May 2012

Development Of Reliability-Based Design For Railway Prestressed Concrete Sleepers, Sakdirat Kaewunruen, Alexander Remennikov, Martin H. Murray

Faculty of Engineering - Papers (Archive)

Faster and heavier train services are a driven improvement aspect for leaner and more profitable transport logistics of either passengers or freights. Ballasted rail track has been adopted for modern railways because of its many superior advantages in design, construction, short- and long-term maintenance, sustainability, financial capital and life cycle cost. An important element of the railway track system, which distributes the wheel load to the formation and holds the rail gauge, is the railway sleeper. Field data has raised concerns about design techniques for prestressed concrete (PC) sleepers. Most current design codes for these rely on allowable stresses and ...


Soac-Net: A Model To Manage Service-Based Business Process Authorization, Haiyang Sun, Jian Yang, Weiliang Zhao, Sanjay K. Nepal Jan 2012

Soac-Net: A Model To Manage Service-Based Business Process Authorization, Haiyang Sun, Jian Yang, Weiliang Zhao, Sanjay K. Nepal

Faculty of Engineering - Papers (Archive)

Business process (BP) can be supported by a large number of resources with evolving contents. In order to receive the support from these resources, the BP must satisfy the authorization policies of these resources. On the other hand, a BP also has its own authorization policies that users must satisfy in order to interact with the BP. Meanwhile, execution policies need to be applied to manage the sequence of tasks invocations in a BP. Therefore, without proper coordination among these policies, BP may not be able to perform correctly, e.g., imperative support from a specific resource could be missing ...


Sensing And Rheological Capabilities Of Mr Elastomers, Weihua Li, Tongfei Tian, Haiping Du Jan 2012

Sensing And Rheological Capabilities Of Mr Elastomers, Weihua Li, Tongfei Tian, Haiping Du

Faculty of Engineering - Papers (Archive)

Magnetorheological elastomers (MREs) are smart materials where polarized particles are suspended in a non-magnetic solid or gel-like matrix. Two kinds of MREs, namely anisotropic and isotropic, are fabricated either under a magnetic field or without a field [1,2]. In anisotropic MREs, polarised particles are arranged in chains within a polymer media such as silicon rubber or natural rubber. The shear modulus of MRE can be controlled by the external magnetic field, which has led to many applications, such as tuned vibration absorbers, dampers and sensors


Dielectric Relaxation In The Dymn1-Xfe Xo3 System, Fang Hong, Zhenxiang Cheng, Shujun Zhang, Xiaolin Wang Jan 2012

Dielectric Relaxation In The Dymn1-Xfe Xo3 System, Fang Hong, Zhenxiang Cheng, Shujun Zhang, Xiaolin Wang

Faculty of Engineering - Papers (Archive)

The dielectric constant and loss of perovskite DyMn1xFexO3 samples show strong dispersion in various frequencies, which is indicative of relaxation. The activation energies were obtained through Arrhenius law fitting and range from 0.213 eV to 0.385 eV. The Fe content dependence of the characteristic frequency f0 and the activation energy Ea shows two transitions that are well consistent with the change in orbital ordering. Meanwhile, different magnetic orderings could affect the relaxation and induce the change in Ea


Rapid Microwave-Assisted Synthesis Of Mn3o4-Graphene Nanocomposite And Its Lithium Storage Properties, Li Li, Zaiping Guo, Aijun Du, Hua-Kun Liu Jan 2012

Rapid Microwave-Assisted Synthesis Of Mn3o4-Graphene Nanocomposite And Its Lithium Storage Properties, Li Li, Zaiping Guo, Aijun Du, Hua-Kun Liu

Faculty of Engineering - Papers (Archive)

A nanocomposite of Mn3O4 wrapped in graphene sheets (GSs) was successfully synthesized via a facile, effective, energy-saving, and scalable microwave hydrothermal technique. The morphology and microstructures of the fabricated GS–Mn3O4 nanocomposite were characterized using various techniques. The results indicate that the particle size of the Mn3O4 particles in the nanocomposite markedly decreased to nearly 20 nm, significantly smaller than that for the bare Mn3O4. Electrochemical measurements demonstrated a high specific capacity of more than 900 mA h g−1 at 40 mA g−1, and excellent cycling stability with no capacity decay can be observed up to 50 cycles ...


Synthesis Of Uniform Tio2@Carbon Composite Nanofibers As Anode For Lithium Ion Batteries With Enhanced Electrochemical Performance, Zunxian Yang, Guodong Du, Qing Meng, Zaiping Guo, Xuebin Yu, Zhixin Chen, Tailiang Guo, Rong Zeng Jan 2012

Synthesis Of Uniform Tio2@Carbon Composite Nanofibers As Anode For Lithium Ion Batteries With Enhanced Electrochemical Performance, Zunxian Yang, Guodong Du, Qing Meng, Zaiping Guo, Xuebin Yu, Zhixin Chen, Tailiang Guo, Rong Zeng

Faculty of Engineering - Papers (Archive)

Very large area, uniform TiO2@carbon composite nanofibers were easily prepared by thermal pyrolysis and oxidization of electrospun titanium(IV) isopropoxide/polyacrylonitrile (PAN) nanofibers in argon. The composite nanostructures exhibit the unique feature of having TiO2 nanocrystals encapsulated inside a porous carbon matrix. The unique orderly-bonded nanostructure, porous characteristics, and highly conductive carbon matrix favour excellent electrochemical performance of the TiO2@carbon nanofiber electrode. The TiO2@carbon hybrid nanofibers exhibited highly reversible capacity of 206 mAh g−1 up to 100 cycles at current density of 30 mA g−1 and excellent cycling stability, indicating that the composite is a ...


Frontier Technologies In Design And Construction For Sustainable Transport Infrastructure, Buddhima Indraratna, Sanjay Shrawan Nimbalkar, Cholachat Rujikiatkamjorn Jan 2012

Frontier Technologies In Design And Construction For Sustainable Transport Infrastructure, Buddhima Indraratna, Sanjay Shrawan Nimbalkar, Cholachat Rujikiatkamjorn

Faculty of Engineering - Papers (Archive)

Railways are expected to be one of the main modes of future transport in rapidly developing countries with high population densities, including Sri Lanka. In spite of recent advances in rail track geotechnology, ballasted tracks progressively degrade under heavy cyclic and impact loading. Field studies often provide significant knowledge to better understand track performance and to extend the current state-of-the-art in design. Therefore, comprehensive field trials were carried out on two instrumented rail tracks in Bulli and in Singleton, New South Wales, Australia. In these studies, several track sections were reinforced with different types of geosynthetics placed beneath the ballast ...


Kinematic Analysis Of Electroactive Polymer Actuators As Soft And Smart Structures With More Dof Than Inputs, Rahim Mutlu, Gursel Alici, Weihua Li Jan 2012

Kinematic Analysis Of Electroactive Polymer Actuators As Soft And Smart Structures With More Dof Than Inputs, Rahim Mutlu, Gursel Alici, Weihua Li

Faculty of Engineering - Papers (Archive)

Electroactive polymer (EAP) actuators have been attracting the attention of researchers due to their muscle-like behaviour and unusual properties. Several modelling methods have been proposed to understand their mechanical, chemical, electrical behaviours or ‘electro-chemo-mechanical’ behaviour. However, estimating the whole shape or configuration of the EAP actuators has always been challenging due to their highly non-linear bending behaviour. This paper reports on an effective method to estimate the whole shape deflection of the EAP actuators by employing a so-called backbone approach. Tri-layer configured polypyrrole (PPy) based EAP actuators were used as a soft and smart structure with more degrees of freedom ...


Precipitation Behavior Of Magnetite In Oxide Scale During Cooling Of Microalloyed Low Carbon Steel, Xianglong Yu, Zhengyi Jiang, Daijun Yang, Dongbin Wei, Quan Yang Jan 2012

Precipitation Behavior Of Magnetite In Oxide Scale During Cooling Of Microalloyed Low Carbon Steel, Xianglong Yu, Zhengyi Jiang, Daijun Yang, Dongbin Wei, Quan Yang

Faculty of Engineering - Papers (Archive)

Precipitation behavior of magnetite particles in the thermal grown oxide scale during isothermal cooling of microalloyed low carbon steel was studied using scanning electron microscopy (SEM) and thin film X-ray. The oxide scale was generated from Gleeble 3500 Thermal-Mechanical Simulator connected with a humid air generator, to simulate 550 and 450°C isothermal treatments. Several types of magnetite precipitates were observed during different cooling processes with respect to the possible mechanisms of precipitation have been discussed. It is found that magnetite particles is as a result of pro-eutectoid precipitation from oxygen-rich wustite, and also as a product of the partial ...


Microstructural Characterisation Of Railhead Damage In Insulated Rail Joints, C Rathod, David Wexler, Tara Chandra, Huijun Li Jan 2012

Microstructural Characterisation Of Railhead Damage In Insulated Rail Joints, C Rathod, David Wexler, Tara Chandra, Huijun Li

Faculty of Engineering - Papers (Archive)

As an integral part the railway network infrastructure, insulated rail joints (IRJs) electrically isolate track segments providing critical feedback to both track signaling and train position detection systems. Because of the discontinuous nature of IRJs, accumulated damage at the railhead is high. Failure modes include plastic flow of metal across joints, bolt and fishplate failures, delamination of insulated material and, as a result of rolling contact fatigue, end post and endpost surface damage. In the current investigation, microstructural changes in the vicinity of endposts of IRJs made from both surface coated and uncoated rail are investigated using techniques of optical ...


Chosen-Ciphertext Secure Anonymous Conditional Proxy Re-Encryption With Keyword Search, Liming Fang, Willy Susilo, Chunpeng Ge, Jiandong Wang Jan 2012

Chosen-Ciphertext Secure Anonymous Conditional Proxy Re-Encryption With Keyword Search, Liming Fang, Willy Susilo, Chunpeng Ge, Jiandong Wang

Faculty of Engineering - Papers (Archive)

Weng et al. introduced the notion of conditional proxy re-encryption (or C-PRE, for short), whereby only the ciphertext satisfying one condition set by the delegator can be transformed by the proxy and then decrypted by delegatee. Nonetheless, they left an open problem on how to construct CCA-secure C-PRE schemes with anonymity. Fang et al. answered this question by presenting a construction of anonymous condi- tional proxy re-encryption (C-PRE) scheme without requiring random oracle. Nev- ertheless, Fang et al.'s scheme only satises the RCCA-security (which is a weaker variant of CCA-security assuming a harmless mauling of the challenge ciphertext is ...


Magnetovolume Effect In Ho2fe17-Xmnx Compounds, Jianli Wang, A J. Studer, S J. Kennedy, R Zeng, S. X. Dou, S J. Campbell Jan 2012

Magnetovolume Effect In Ho2fe17-Xmnx Compounds, Jianli Wang, A J. Studer, S J. Kennedy, R Zeng, S. X. Dou, S J. Campbell

Faculty of Engineering - Papers (Archive)

The structural and magnetic properties of seven compounds in the Ho2Fe17-xMnx series (x = 0-5) have been investigated. The spontaneous magnetization Ms at 10 K exhibits a minimum at x ≈ 3.8 while the 3d-sublattice magnetization MT is found to decrease at ∼ −3.4 μB/per Mn atom compared with the rate of ∼−2.0 μB/per Mn atom expected from a simple dilution model. All of the Ho2Fe17-xMnx compounds exhibit anisotropic thermal expansion below their Curie temperatures leading to the presence of strong magnetovolume ...


Development Of A Metallurgical Coke Analogue To Investigate The Effects Of Coke Mineralogy On Coke Reactivity, Raymond Longbottom, Brian J. Monaghan, Oliver Scholes, Merrick R. Mahoney Jan 2012

Development Of A Metallurgical Coke Analogue To Investigate The Effects Of Coke Mineralogy On Coke Reactivity, Raymond Longbottom, Brian J. Monaghan, Oliver Scholes, Merrick R. Mahoney

Faculty of Engineering - Papers (Archive)

In this study the suitability of a laboratory analogue for coke for studying the effects of minerals on the reactivity of coke was evaluated. In addition to this, the effects of different physical properties and production conditions on the reactivity of the coke analogue were also tested. The coke analogue was used for control testing of specific mineral, and to some degree maceral, effects on reactivity. Such information would improve our fundamental understanding of coke reactivity behaviour and could be used to develop more accurate predictive models of coke strength after reaction (CSR) or associated indices and coke properties. The ...


A Validated Thermal Model Of Bead-On-Plate Welding, Djarot Darmadi, A K. Tieu, John Norrish Jan 2012

A Validated Thermal Model Of Bead-On-Plate Welding, Djarot Darmadi, A K. Tieu, John Norrish

Faculty of Engineering - Papers (Archive)

In this paper, finite element model is used to carry out thermal analysis of bead-on-plate welding. The model followed the proposed five step strategies which were then built into a model to obtain temperature history at the positions of thermocouples. Temperature field was also evaluated by comparing predicted weld bead with the actual weld bead. Using these proposed strategies, well matched temperature histories and temperature field have been obtained.


Hydrogen De-/Absorption Improvement Of Nabh4 Catalyzed By Titanium-Based Additives, Jianfeng Mao, Zaiping Guo, Ivan P. Nevirkovets, Hua-Kun Liu, S. X. Dou Jan 2012

Hydrogen De-/Absorption Improvement Of Nabh4 Catalyzed By Titanium-Based Additives, Jianfeng Mao, Zaiping Guo, Ivan P. Nevirkovets, Hua-Kun Liu, S. X. Dou

Faculty of Engineering - Papers (Archive)

NaBH4 is considered as a promising candidate material for solid-state hydrogen storage due to its high hydrogen content of 10.6 wt %. However, its practical use is hampered by its high thermodynamic stability and slow H-exchange kinetics. In the present work, the effects of Ti-based additives, including Ti, TiH2, and TiF3, on the dehydrogenation and rehydrogenation of NaBH4 (NaH+B) were investigated. It was revealed that all of the titanium-based additives were effective in improving the hydrogen desorption and absorption reactions of NaBH4, and, among them, TiF3 possessed the highest catalytic activity. The whole dehydrogenation process for the NaBH4–0 ...


Crossing Point Phenomena () In Specific Heat Curves Of Superconducting Ferromagnets, Anuj Kumar, R P. Tandon, Jianli Wang, Rong Zeng, V P. S Awana Jan 2012

Crossing Point Phenomena () In Specific Heat Curves Of Superconducting Ferromagnets, Anuj Kumar, R P. Tandon, Jianli Wang, Rong Zeng, V P. S Awana

Faculty of Engineering - Papers (Archive)

Crossing point phenomena are one of the interesting and still puzzling effects in strongly correlated electron systems. We have synthesized RuSr2Gd1.4Ce0.6Cu2O10-delta (GdRu-1222) magneto-superconductor through the standard solid state reaction route and measured its magnetic, transport, and thermal properties. We also synthesized RuSr2Eu1.4Ce0.6Cu2O10-delta (EuRu-1222) then measured its heat capacity in zero magnetic fields for reference. The studied compounds crystallized in the tetragonal structure with space group I4/mmm. To explore the crossing point phenomena, the specific heat [C-p (T)] was investigated in the temperature range 1.9-250 K, under magnetic field of up to 70 kOe. Unfortunately ...


Infrared Phonon Anomaly And Magnetic Excitations In Single-Crystal Cu3bi(Seo3)2o2cl, K H. Miller, P W. Stephens, C Martin, E Constable, R A. Lewis, H Berger, G L. Carr, D B. Tanner Jan 2012

Infrared Phonon Anomaly And Magnetic Excitations In Single-Crystal Cu3bi(Seo3)2o2cl, K H. Miller, P W. Stephens, C Martin, E Constable, R A. Lewis, H Berger, G L. Carr, D B. Tanner

Faculty of Engineering - Papers (Archive)

nfrared reflection and transmission as a function of temperature have been measured on single crystals of Cu3Bi(SeO3)2O2Cl. The complex dielectric function and optical properties along all three principal axes of the orthorhombic cell were obtained via Kramers-Kronig analysis and by fits to a Drude-Lorentz model. Below 115 K, 16 additional modes [8(E∥â)+6(E∥b̂)+2(E∥ĉ)] appear in the phonon spectra; however, powder x-ray diffraction measurements do not detect a new structure at 85 K. Potential explanations for the new phonon modes are discussed. Transmission in the far ...


Use Of The Soil Modulus For Compaction Control Of Compacted Soils, Ana Heitor, Buddhima Indraratna, Cholachat Rujikiatkamjorn Jan 2012

Use Of The Soil Modulus For Compaction Control Of Compacted Soils, Ana Heitor, Buddhima Indraratna, Cholachat Rujikiatkamjorn

Faculty of Engineering - Papers (Archive)

Insufficient compaction conditions can cause significant roadway infrastructure maintenance costs. Conventional compaction control, using nuclear methods, is based on the discrete in situ determination of the dry density and moisture content. Recently, there has been an increase interest in alternative methods for compaction control using intelligent compaction technologies. This method enables the continuous measurement of the soil modulus and the degree of compaction on the layer that is being compacted. Thus, the efficiency of the compaction process can be maximized. Although the adoption of this method is very promising, it constitutes a change of project specification for the contractors (i ...


Normalized Confinement Stiffness Approach For Modeling Frp-Confined Concrete, Veysel Yazici, Muhammad N. S Hadi Jan 2012

Normalized Confinement Stiffness Approach For Modeling Frp-Confined Concrete, Veysel Yazici, Muhammad N. S Hadi

Faculty of Engineering - Papers (Archive)

Passive confinement provided by fiber-reinforced polymer (FRP) jackets increases the compressive strength and axial deformation capacity of concrete. This study explains a normalized confinement stiffness approach to quantify the strength and strain increase of FRP confined concrete using a previously proposed and most widely-used model for both active and passive confinement of concrete, and claims that these equations can still be used for FRP-confined concrete with very simple modifications. A comparison of the proposed model's accuracy to American Concrete Institute guidelines was made using experimental results reported in the literature. The proposed modified model was shown to be quite ...


Numerical Simulation Of Fully Grouted Rock Bolts, Hossein Jalalifar, Naj Aziz Jan 2012

Numerical Simulation Of Fully Grouted Rock Bolts, Hossein Jalalifar, Naj Aziz

Faculty of Engineering - Papers (Archive)

This chapter describes the application of numerical modelling to civil and mining projects, particularly rock bolting, developing a Final Element (FE) model for the bolt, grout, rock, and two interfaces under axial and lateral loading, verifying the model, analysing the stress and strains developed in the bolt and surrounding materials. Numerical methods are the most versatile computational methods for various engineering disciplines because a structure is discritised into small elements and the constitutive equations that describe the individual elements and their interactions are constructed. Finally, these numerous equations are solved together simultaneously using computers. The results from this procedure include ...


Decision Support: Informing Flood Management, R Laine, C Cook, B Lemass Jan 2012

Decision Support: Informing Flood Management, R Laine, C Cook, B Lemass

Faculty of Engineering - Papers (Archive)

This paper describes the development of a new flood management decision support system which significantly improves the ability of flood practitioners to: 1) Identify adaptation and mitigation solutions to flood inundation; 2) Facilitate objective community flood risk management consultation and 3) Justify floodplain management decisions in a transparent and structured manner to all stakeholders. The nature of a Decision Support System (DSS) and its place in floodplain management is described and it is shown how a DSS can be used as a practical tool to identify options available to flood management practitioners. The new flood management system presented in this ...


Dyni2mn—Magnetisation And Mössbauer Spectroscopy, Jianli Wang, Stewart James Campbell, Shane Joseph Kennedy, S. X. Dou, Guang Heng Wu Jan 2012

Dyni2mn—Magnetisation And Mössbauer Spectroscopy, Jianli Wang, Stewart James Campbell, Shane Joseph Kennedy, S. X. Dou, Guang Heng Wu

Faculty of Engineering - Papers (Archive)

The physical properties of DyNi2Mn doped with 57Fe have been investigated by X-ray diffraction, magnetisation (10–300 K) and 57Fe Mössbauer spectroscopy measurements (5–300 K). DyNi2Mn(57Fe) crystallizes in the MgCu2-type cubic structure (Fd−3m space group). The ordering temperature is found to be TC = 99(2) K, much higher than those of DyNi2 (∼22 K) and DyMn2 (∼35 K). Analyses of isothermal M–H curves and the related Arrott plots confirm that the magnetic phase transition at TC is second order. The magnetic entropy change around TC is 4.0 J/kg K for a magnetic field change ...


Microstructural Evolution During Gaseous Hydrogen Charging Of Zircaloy-4 Processed By High-Pressure Torsion: A Comparative Study, Zhiyang Wang, Huijun Li, Ulf Garbe, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao Jan 2012

Microstructural Evolution During Gaseous Hydrogen Charging Of Zircaloy-4 Processed By High-Pressure Torsion: A Comparative Study, Zhiyang Wang, Huijun Li, Ulf Garbe, Mark D. Callaghan, Yanbo Wang, Xiaozhou Liao

Faculty of Engineering - Papers (Archive)

The original and high-pressure torsion (HPT) processed Zircaloy-4 materials were hydrided using gaseous hydrogen charging at different hydrogen pressures (10, 15 and 20 atm). The phase and microstructural evolutions of the samples during hydriding were characterized. It showed that when hydriding at the identical conditions, more hydrides tended to form in the HPT samples compared to that of the original ones. At a hydrogen pressure of 20 atm, the HPT sample was completely converted to ε-ZrH2 while some δ-ZrH1.66 hydrides (volume fraction ~5.73%) were present in the material without HPT preprocessing. The HPT samples exhibited high potential for ...