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Slope Stability Enhancement Of An Upstream Tailings Dam: Laboratory Testing And Numerical Modelling, Yazeed A. Alsharedah

Electronic Thesis and Dissertation Repository

Mine tailings are the byproduct of mining activities, which need to be disposed of once the ore is extracted. They can be disposed of in either dry or wet forms. The latter is most common with the tailings being disposed of in the form of slurry inside retention structures. The retention structure may be a natural, manmade, or built dam, which is the case in most of nowadays mining locations. In this thesis, improving the stability of an upstream tailings dam using soil additives is investigated. The experimental phase of this study involved laboratory tests conducted to characterize mine tailings …

Smouldering Remediation: Transient Effects Of Front Propagation, Laura L. Kinsman

Electronic Thesis and Dissertation Repository

Remediation of sites contaminated with non-aqueous phase liquids (NAPLs) presents a significant challenge, particularly for complex and high molecular weight compounds such as coal tar and creosote. Self-sustaining Treatment for Active Remediation (STAR) is an innovative remediation technology based on the principles of smouldering combustion, which has shown potential for rapid destruction of source zone contaminants. The success of smouldering remediation has been previously demonstrated both at the laboratory and field scale, however, these studies have focused primarily on the overall degree of remediation. Laboratory column experiments were employed to identify key transient processes that have the potential to influence …

Investigation Of Hybrid Foundation System For Offshore Wind Turbine, Ahmed Mohamed Reda Abdelkader

Electronic Thesis and Dissertation Repository

Green energy resources are essential to meet the growing energy demands in the near future while reducing the effects of global warming. Offshore wind energy is one of the main efficient renewable energy sources which drive the ever increasing expansion of offshore wind farms globally. Wind energy technologies are improving making energy production more affordable, which helped Denmark, for example, to produce about 25% of its energy. One of the main challenges for offshore wind projects is the cost of foundation construction, which represents about 40% of the total cost. The investigated hybrid foundation system has the potential to reduce …

Silver Nanoparticle Transport Through Soil: Illuminating The Governing Pore-Scale Processes, Ian L. Molnar

Electronic Thesis and Dissertation Repository

Engineered nanoparticles are widely used and will eventually be released to the subsurface environment and contaminate groundwater resources. However, the transport of engineered nanoparticles through soil is currently not well understood and cannot be modelled in any fundamental manner, placing groundwater resources at risk from nanoparticle contamination. This inability to accurately simulate transport is due to a lack of experimental information on nanoparticle interactions in the pore spaces of real soils.

This thesis illuminates the pore-scale processes governing silver nanoparticle transport through soil. In addition, it examines the influence of surface chemistry and grain/pore distributions on those processes. For the …

Application Of 3d Printing Technology In Porous Anode Fabrication For Enhanced Power Output Of Microbial Fuel Cells, Bin Bian

Electronic Thesis and Dissertation Repository

Microbial fuel cells (MFCs) are widely researched for application in wastewater treatment. However, the current anodes used in MFCs often suffer from high fabrication cost and uncontrollable pore sizes. In this thesis, three-dimensional printing technique was utilized to fabricate anodes with different micro pore sizes for MFCs. Copper coating and carbonization were applied to the printed polymer anodes to increase the conductivity and specific surface area. Voltages of MFCs with various anodes were measured as well as other electrochemical tests such as linear sweep voltammetry and electrochemical impedance spectroscopy. 3D copper porous anode produced higher maximum voltages and power densities …

Shear And Peel Stresses At The Interface Between Hollowcore Slabs And The Topping Concrete, Aiham Adawi

Electronic Thesis and Dissertation Repository

Hollowcore slabs are used in floors and roofs of residential, commercial, industrial and institutional buildings. They are precast/prestressed concrete elements produced using the extrusion process. Their surface finish can be “machine-cast” or “intentionally roughened”. A typical floor consists of a number of hollowcore slabs that are connected together. Prestressing causes hollowcore slabs to camber, which results in an uneven floor surface. A 50 mm topping concrete is commonly cast to level the floor surface. To avoid delamination, engineers require bonding agents to be applied on the hollowcore slab surface before pouring the topping concrete. The concrete topping can be used …

Influence Of Waves On Groundwater Flows And Geochemistry In A Sandy Nearshore Aquifer: A Combined Field And Modelling Study, Spencer S. Malott

Electronic Thesis and Dissertation Repository

Waves are known to influence the flux of pollutants to coastal waters via groundwater discharge. This study combines field measurements with numerical groundwater modelling to evaluate the influence of a period of intensified wave conditions (wave event) on nearshore groundwater flows and geochemistry in a sandy freshwater beach. Comprehensive vertical nested pressure transducer data obtained over a 2.5 day isolated wave event reveal the development of transient groundwater flow recirculations through the nearshore aquifer combined with enhanced water exchange across the sediment-water interface (i.e., beach face). The wave-induced groundwater flows were simulated in FEFLOW using a phase-averaged wave setup approach …

Behaviour Of Helical Pile Connectors For New Foundations, Muhammad Ahmad Muhammad Diab

Electronic Thesis and Dissertation Repository

Despite the wide application of the connections between slender pile types, which end with a mono steel bar at the ground level (e.g. helical piles and micro piles), and new reinforced concrete foundations with limited width (e.g. RC grade beams) in the piling industry in North America, neither a clear understanding of the connections' behaviour nor a specific design criteria for their implementation is presented.

The main goal of this research was to clearly understand the behaviour of these connections and their failure mechanism under monotonic and cyclic loadings. The research methodology involved conducting experimental tests on 33 full-scale pile-foundation …

Fundamentals Of Electro-Flotation And Electrophoresis And Applications In Oil Sand Tailings Management, Raquibul Alam

Electronic Thesis and Dissertation Repository

This thesis addresses two challenges facing the management of mature fine tailings (MFT) from oil sand processing. The first challenge is the high concentration of residual bitumen in tailings ponds, which poses a hazard to aquatic biota and impact to the environment. A laboratory scale study is carried out to assess the suitability of electro-flotation (EF) for removal of bitumen from oil sand tailings slurry. The results of the study confirm that EF is effective to reduce bitumen contents of tailings slurry. At a current density 150 A/m², the bitumen concentration is reduced from 106.8 mg/L to less …

Morphological Response Of Sand Bed Streams To Unsteady Flow Events: An Experimental Study, Etta Haley Gunsolus

Electronic Thesis and Dissertation Repository

Changes in riverine discharge, such as those due to reservoir flushing, seasonal variation or extreme precipitation events, can alter sediment transport rates and morphology of the stream bed. Experimental research investigated the effect of unsteady flow event hydrographs on stream bed morphological response. Laboratory experiments were conducted in a 5.0 m-long sediment transport flume with a bed comprised of a medium sand. Experimental hydrographs were composed of antecedent (base-flow), unsteady event (flood) and post- flood (return to base-flow) stages. Three distinct series of experimental laboratory runs were conducted to systematically investigate the effect of three characteristics of unsteady flow event …

Tropical Cyclone Wind Hazard Assessment For Southeast Part Of Coastal Region Of China, Sihan Li

Electronic Thesis and Dissertation Repository

Tropical cyclone (TC) or typhoon wind hazard and risk are significant for China. The return period value of the maximum typhoon wind speed is used to characterize the typhoon wind hazard and assign wind load in building design code. Since the historical surface observations of typhoon wind speed are often scarce and of short period, the typhoon wind hazard assessment is often carried out using the wind field model and TC track model. For a few major cities in the coastal region of mainland China, simple or approximated wind field models and a circular subregion method (CSM) have been used …

Self-Sustaining Smouldering Combustion As A Novel Disposal Destruction Method For Waste Water Biosolids, Tarek L. Rashwan

Electronic Thesis and Dissertation Repository

Managing biosolids, the major by-product from wastewater treatment plants (WWTPs), persists as a major global challenge that often constitutes the majority of WWTP operating costs. Self-sustained smouldering is a new approach for organic waste treatment, in which the waste (i.e., the fuel) is destroyed in an energy efficient manner after mixing it with sand. Smouldering has never been applied to biosolids. Column experiments, using biosolids obtained from a WWTP, were employed to identify if - and under what conditions - smouldering could be used for treating biosolids. The parameter space in which smouldering was self-sustaining was mapped as a function …

Evaluation Of Filtration Performance Of A Rotating Belt Filter For Different Primary Wastewater Influents., Tulip Chakraborty

Electronic Thesis and Dissertation Repository

Human activities around the world are responsible for production of enormous amount of wastewater, which needs to be treated quickly and effectively to avoid environmental concerns and other health implications. As an alternative to primary settlers in treating municipal wastewater, Salsnes, a subsidiary company of Trojan Technologies offers rotating belt filters (RBF) to treat the wastewater. A bench scale filtration unit of the RBF was developed to investigate the effect of varying water qualities from several wastewater plants in London, Ontario on the performance of the filter. The unit can achieve up to 80% reduction in total suspended solids (TSS), …

Field Scale Application Of Nanoscale Zero Valent Iron: Mobility, Contaminant Degradation, And Impact On Microbial Communities, Chris M.D. Kocur

Electronic Thesis and Dissertation Repository

This thesis began by verifying that nanoscale zero valent iron (nZVI) synthesis methods could be scaled up and implemented at the field scale in a safe manner. This led to successful demonstration of nZVI injection and mobility under constant head gravity injection into a contaminated utility corridor in Sarnia, Ontario. Where field studies have fallen short in the past was linking the somewhat qualitative field geochemical parameters to other evidence of nZVI transport. Definitive nZVI detection was elusive in previous field studies due to the highly reactive nature of the particles caused by their high surface area. nZVI was detected …

The Effects Of Volatile Fatty Acids On The Performance Of Microbial Electrolysis Cells, Nan Yang

Electronic Thesis and Dissertation Repository

This study investigated the performance of microbial electrolysis cells (MECs) fed with three common fermentation products: acetate, butyrate, and propionate. Each substrate was fed to the reactor for three consecutive-batch cycles. The results showed high current densities for acetate, but low current densities for butyrate and propionate (maximum values were 6.0 ± 0.28, 2.5 ± 0.06, 1.6 ± 0.14 A/m², respectively). Acetate also showed a higher coulombic efficiency of 87 ± 5.7 % compared to 72 ± 2.0 and 51 ± 6.4 % for butyrate and propionate, respectively. This paper also revealed that acetate could be easily oxidized …

Evaluation Of Gauge-Radar Merging Methods For Quantitative Precipitation Estimation In Hydrology: A Case Study In The Upper Thames River Basin, Jack L. Mckee

Electronic Thesis and Dissertation Repository

Hydrological models rely on accurate precipitation data in order to produce results with a high degree of confidence and serve as valuable flood forecasting and warning tools. Gauge-radar merging methods combine rainfall estimates from rain gauges and weather radar in order to capitalize on the strengths of the individual instruments and produce precipitation data with greater accuracy for input to hydrological models. A comprehensive review of gauge-radar merging methods reveals that there is an opportunity for near-real time application in hydrological models. The performance of four well known gauge-radar merging methods, including mean field bias correction, Brandes spatial adjustment, local …

Performance Of Protective Perimeter Walls Subjected To Explosions In Reducing The Blast Resultants On Buildings, Fada Casi F Alsubaei

Electronic Thesis and Dissertation Repository

The existing methods to predict the blast effects on structures located behind blast walls are based on plane rigid walls and the results of small-scale studies, which are not validated by the results of full-scale experiments. Hence, they are only valid for a very limited range of scaled parameters. Also, they do not account for the impact of non-spherical charges or for different ignition points; they also put their emphasis on mid-and far-field overpressures.

The current thesis investigates blast wave propagations created by cuboid charges and their effects on structural members at close-in and nearby ranges. First, a preliminary numerical …

Process Control For Biological Nutrient Removal Processes In Fluidized Beds Treating Low Carbon To Nitrogen Municipal Wastewater, Joseph Donohue

Electronic Thesis and Dissertation Repository

Conventional wastewater treatment techniques - utilizing microorganisms to remove organics and nutrients (i.e. nitrogen and phosphorus) from a water stream and partially incorporate them into their cell structure - struggle to adapt with increased urbanization due to land and infrastructure requirements. The circulating fluidized-bed bioreactor (CFBBR) was developed as a way to provide biological treatment in an urbanized area by cultivating high-density bacteria on an inert media. The technology operates as a pre-anoxic nitrification/denitrification wastewater treatment process. The system is initially loaded with media, providing a platform for microbial growth. Internal recycle streams in the system provide the energy to …

An Approach To Developing A Spatio-Temporal Composite Measure Of Climate Change-Related Human Health Impacts In Urban Environments, Mohammad Amin Owrangi

Electronic Thesis and Dissertation Repository

Introduction:

Rapid population growth along with an increase in the frequency and intensity of climate change-related impacts in costal urban environments emphasize the need for the development of new tools to help disaster planners and policy makers select and prioritize mitigation and adaptation measures. Using the concept of the resilience of a community, which is a measure of how rapidly the community can recover to its previous level of functionality following a disruptive event is still a relatively new concept for many engineers, planners and policy makers, but is becoming recognized as an increasingly important and some would argue, essential …

Assessment Of The Regionalization Of Precipitation In Two Canadian Climate Regions: A Fuzzy Clustering Approach, Sarah E. Irwin

Electronic Thesis and Dissertation Repository

Regional frequency analysis (RFA) is used to obtain reliable estimates of local precipitation events for a variety of applications in water resources engineering. The focus of the presented research is on an initial step of the RFA process; that is the formation of precipitation regions (also referred to as regionalization). The aim of this study is to dissect the regionalization procedure into its individual components that require subjective user input, and to evaluate their respective influences on the results. All assessments are conducted in two of Canada's climate regions; namely the Prairie and Great Lakes-St. Lawrence lowlands. Additionally, a new …

Statistical Analyses Of Historical Pipeline Incident Data With Application To The Risk Assessment Of Onshore Natural Gas Transmission Pipelines, Chio Lam

Electronic Thesis and Dissertation Repository

Statistical analyses of the pipe-related incident data for onshore gas transmission pipelines between 2002 and 2013 collected by the Pipeline and Hazardous Material Safety Administration (PHMSA) of the United States Department of Transportation (DOT) are conducted. It is found that the total length of the onshore gas transmission pipelines in the US is approximately 480,000 km as of 2013. The third-party interference, external corrosion, material failure and internal corrosion are the leading causes for the pipe-related incidents, responsible for over 75% of the total incidents between 2002 and 2013. Based on the pipeline mileage and incident data, the average rate …

Monotonic And Cyclic Performance Of Spun-Cast Ductile Iron Helical Tapered Piles, Ahmed Fahmy

Electronic Thesis and Dissertation Repository

The performance of a novel piling system is investigated, which involves a spun-cast ductile iron (SCDI) tapered shaft fitted with a lower helical plate. It combines the efficiency of the tapered section, the competitive cost, effectiveness and durability of spun cast ductile iron with a rough surface and the construction advantages of helical piles. The system is installed using a fast, low vibration and reduced noise process. Seven instrumented piles including five SCDI tapered and two steel straight pipes were installed in sand using mechanical torque. The piles were subjected to cyclic and monotonic compression, uplift and lateral load tests. …

Application Of Polyurethane Products In Accelerated Construction Of Innovative Noise Barrier, Bahman Daee

Electronic Thesis and Dissertation Repository

Noise barriers (sound walls) are usually constructed along roadways to mitigate the airborne noise emanating from vehicles. They are currently built using various materials including precast concrete panels, masonry, wood and transparent sheets. The main challenge in roadside construction is the obstruction of roadways during the construction, which may result in traffic congestion, public dissatisfaction, car collision and subsequently fatalities. In order to decrease the risk of roadside construction, accelerated and non-obstructive methods are highly preferred by transportation authorities.

An innovative wall system comprised of polyurethane products is proposed, developed and investigated for application in accelerated construction of noise barriers. …

Stormwater Management Performance Of Green Roofs, Andrew W. Sims

Electronic Thesis and Dissertation Repository

Green roofs are gaining recognition in North America as effective tools for managing stormwater runoff in urban areas. A greater understanding of how green roofs perform with respect to fundamental stormwater management criteria, such as stormwater retention and peak flow attenuation is required. This study investigated the impact that changing climates have on the retention performance of three green roofs in London, Calgary, and Halifax. It was found that Calgary (67%) has significantly better retention performance then both London (48%) and Halifax (34%). However, London retained the greatest volume of stormwater (758 mm), followed by Halifax (517 mm) then Calgary …

Design Wind Loads For Solar Modules Mounted Parallel To The Roof Of A Low-Rise Building, Sarah Elizabeth Stenabaugh

Electronic Thesis and Dissertation Repository

To assess the wind induced pressures on an array of solar modules mounted parallel to the roof surface of a low-rise building, wind tunnel studies were conducted on an array on a 1/20 scale building model with either a flat roof or a 30° roof slope. The spacing between individual modules, G, and the mounting height above the roof surface, H, were studied. Large G yielded improved wind resistance by lowering the external peak suctions and peak net suctions. Large H beyond a small cavity depth was determined to be detrimental for wind resistance as the peak external …

Experimental And Numerical Study On Full-Scale Precast Steel Fibre-Reinforced Concrete Pipes, Nedal Mohamed

Electronic Thesis and Dissertation Repository

Reinforced concrete (RC) pipes are widely used as open channels (non-pressurized pipes) for sewage and storm water conveyance. RC pipes have generally achieved a reliable long-term performance. Depending on multiple parameters (e.g. pipe diameter, pipe wall thickness, required strength, etc.) the pipe may have up to three welded reinforcement cages in order to resist anticipated loads. Each cage is an assembled unit of steel reinforcement consisting of circumferential and longitudinal bars or wires. The fabrication process of a steel cage reinforcement is time and labour consuming. Thus, eliminating the steel cage reinforcement will yield an overall reduction in the production …

Multi-Method Modeling Framework For Support Of Integrated Water Resources Management, Vladimir V. Nikolic

Electronic Thesis and Dissertation Repository

The existing definition of integrated water resources management (IWRM) promotes a holistic approach to water resources management practice. The IWRM deals with planning, design and operation of complex systems in order to control the quantity, quality, temporal and spatial distribution of water with the main objective of meeting human and ecological needs and providing protection from water disasters. One of the main challenges of IWRM is development of tools for operational implementation of the concept and dynamic coupling of physical and socio-economic components of water resources systems. This research examines the role of simulation in IWRM practices, analyses the advantages …

Helical Pile Installation Torque And Capacity Correlations, Jared Louis Harnish

Electronic Thesis and Dissertation Repository

Large diameter helical piles are being utilized increasingly to support large compressive and tensile loads. Both the magnitude of the required installation torque and the pile capacity can be directly attributed to the soil shearing resistance developed over the embedded area of the pile including the shaft and helical plates. Hence, the pile capacity can be correlated to the installation torque. Such correlations are widely used in helical pile industry as a means for quality control/quality assurance. However, the reliability of capacity-torque correlations for predicting the large diameter helical piles is adversely affected by the inaccurate measurement of the installation …

Static And Dynamic Response Of Silty Toyoura Sand With Pva Fibre And Cement Additives, Colin J.R. Schmidt

Electronic Thesis and Dissertation Repository

After the Great East Japan Earthquake of 2011, nearly 24 million tons of disaster debris such as concrete products, natural and polymeric fibres, and tsunami deposits remained on the coast of Japan. Much of this debris was recycled and repurposed in engineering projects such as embankments, park restoration, and agricultural field restoration around Tokyo Bay, one of the hardest hit regions of the country. Such a major disaster developed a need for the stabilization of the liquefaction susceptible regions of the reclaimed Tokyo Bay coastline. This thesis specifically focuses on the stabilization against liquefaction of Toyoura sand with the typical …

A Self-Potential For Monitoring Self-Sustaining Treatment For Active Remediation (Star), Mehrnoosh Ebrahimzadeh

Electronic Thesis and Dissertation Repository

Self-sustaining Treatment for Active Remediation (STAR) is a novel soil remediation approach for Non-Aqueous Phase liquids (NAPLs) embedded in a porous medium. STAR is based on liquid smoldering combustion which destroys NAPLs while simultaneously generating heat due to the exothermic oxidation reaction. The technique is currently in use in several field pilot tests and a full-scale site remediation. Propagation of the smoldering front is monitored in the field by temperature data obtained from a thermocouple network, with limited resolution. Geophysical techniques, such as Self-Potential (SP), have potential as a non-destructive means for monitoring remediation processes. The SP method measures natural …