Digital Commons Network^™

Liquid Phase Nano Metal Catalyzed Dechlorination Of Chlorinated Organic Compounds, Omneya El-Sharnouby

Electronic Thesis and Dissertation Repository

1,2-Dichloroethane (1,2-DCA) is among the most prevalent groundwater chlorinated organic compounds (COCs) found at hazardous sites throughout the world. Given its pervasive contamination and adverse health effects, there is considerable interest in developing novel remediation technologies for successfully treating 1,2-DCA along with other COCs from water sources. Chemical reduction by nano zero valent iron (monometallic (nZVI) or bimetallic (Pd-nZVI)) has proven to be a successful field applicable technology, yet it has failed in degrading such a recalcitrant compound as 1,2-DCA.

In this study, the development of a field applicable nano metal based technology capable of degrading 1,2-DCA was carried out. …

Investigation Of Grouted Dowel Connection For Precast Concrete Wall Construction, Douglas J. Provost-Smith

Electronic Thesis and Dissertation Repository

The grouted dowel connection is a simple and cost-effective connection used in many precast concrete structural systems. The required dowel length is currently designed as a regular bar in reinforced concrete, which underestimates the bond strength, thus resulting in excessive connection lengths. Furthermore, precast wall construction continues throughout cold weather, where in-situ heating of the grout used in the grouted dowel connections is usually conducted for short periods of time. Hence, early-age exposure to subfreezing conditions may affect the quality of the grout and subsequently the bond strength of the connection, which can compromise structural integrity.

In this thesis, full-scale …

Combined Analysis Of Tide- And Wave-Induced Water Table Fluctuations For Structural Characterization Of A Coastal Aquifer, Victoria A. Trglavcnik

Electronic Thesis and Dissertation Repository

Understanding of coastal hydrogeology is essential for the assessment, management, and protection of coastal groundwater resources. Coastal groundwater is often an important source of drinking water for coastal communities but can be contaminated by saltwater or human-derived contaminants. The groundwater table in coastal aquifers fluctuates in response to various oceanic pressure forces acting at the shoreline, including tides, individual waves, and offshore storms. Measurements of water table fluctuations in response to tides and waves can be used to characterize coastal aquifers and provide important insight into the hydraulic properties and structure, including the connectivity between the aquifer and ocean. Most …

Development Of Design Loads For Transmission Line Structures Subjected To Downbursts Using Aero-Elastic Testing And Numerical Modeling, Amal Elawady

Electronic Thesis and Dissertation Repository

The failure of transmission line structures due to severe High Intensity Wind (HIW) events is one of the major problems facing the electrical utility companies in various places around the globe including Canada. An extensive research program focusing on this problem started about fifteen years ago at The University of Western Ontario (UWO). In this Thesis, two major milestones are achieved leading to the advancement of the knowledge in this field. The first milestone is conducting, for the first time, a test on an aero-elastic model of a multi-span transmission system under reduced–scale simulated downbursts. The first objective of the …

Fate Of Benzalkonium Chlorides In Natural Environment And Treatment Processes, Adnan Hossain Khan

Electronic Thesis and Dissertation Repository

Benzalkonium chlorides (BACs) are a type of cationic surfactant and are highly adsorptive to negatively charged surfaces during the wastewater treatment process. They can, therefore, enter the aquatic environment via the suspended organic matter in wastewater effluents, and the terrestrial environment through the application of biosolids as a soil amendment for crop production or by the use of reclaimed wastewater for irrigation. This research investigated the fate of the two most commonly used BACs, benzyl dimethyl dodecyl ammonium chloride (BDDA; C₁₂-alkyl chain) and benzyl dimethyl tetradecyl ammonium chloride (BDTA; C₁₄-alkyl chain), individually and in mixture in …

Channel Form And Processes In A Formerly Glaciated Terrain, Nathaniel Bergman

Electronic Thesis and Dissertation Repository

Despite that many places around the world in general, and North America in particular, were glaciated during the last ice age, relatively little is known about rivers that evolved over these landscapes once they deglaciated. These rivers are commonly categorized as alluvial with a glacial legacy, and often described as plain gravel-bed or sand-bed rivers. Alternatively, they are considered to be bedrock rivers when the glacial deposits were eroded and underlying rock was exposed. However, ignoring the glacial history of these rivers is scientifically wrong and they should be termed "semi-alluvial". This work shows that classification is important, not only …

Behavior Of Fire-Exposed Rc Frames Before And After Jacketing, M. Monir M. Ajan Alhadid

Electronic Thesis and Dissertation Repository

Analysis and design of fire-exposed Reinforced Concrete (RC) frames before and after jacketing with concrete layers are commonly performed using prescriptive methods that rely on the concept of fire rating. These methods were developed based on empirical results on individual RC members subjected to certain fire conditions. In typical fire scenarios, the residual capacity, stiffness and thermal deformations affects not only the local performance of each fire-exposed member, but also the load redistribution and global behavior of the entire frame. In terms of fire safety, the philosophy of the new building codes considers objective-based design as an alternative of the …

Multiscale Wind Modelling For Sustainability And Resilience, Djordje Romanic

Electronic Thesis and Dissertation Repository

The research presented herein is a mix of meteorological and wind engineering disciplines. In many cases, there is a gap between these two fields and this thesis is an attempt to bridge that gap through multiscale wind modelling approaches. Data and methods used in this study cover a multitude of spatial and temporal scales. Applications are in the fields of sustainability and resilience. This relationship between multiscale wind modelling and sustainability and resilience is investigated examining several case studies of three different developments: urban, rural and coastal.

An urban wind modelling methodology is proposed and applied for a specific development …

The Effects Of Furfural On Biological Hydrogen Production In Batch And Microbial Electrolysis Cell, Hyeongu Yeo

Electronic Thesis and Dissertation Repository

Furfural inhibits biohydrogen production and numerous studies has been carried out on detoxification of furfural to enhance biofuel production. Electrochemical detoxification of furfural is a new approach to remove furfural without the degradation of sugars. However, there is limited information on the effects of the degradation products of furfural on biohydrogen production in batch tests and the impact of furfural on anode-respiring bacteria (ARB) in microbial electrolysis cells (MECs). This study investigated the effect of furfural and its derivatives, furfuryl alcohol (FFA) and 2-furoic acid (FA), on biohydrogen production. The impact of furfural on hydrogen production in MECs was also …

Foundation Effects Of Trees Under Wind Loads, Padmavathi Venkata Sagi

Electronic Thesis and Dissertation Repository

Winching tests were conducted on a mature 24-year-old Norway spruce tree. The tree was instrumented with strain gauges along the root structure and tilt sensors along the tree stem and was winched to failure. Tracked tree-root system response to failure load and the material properties of the tree-root-soil system were used to examine the applicability of simple engineering principles to tree stability analysis. Tree stability was studied using the principles of Winkler foundation model for the first time. In order to study the very complex windthrow phenomenon, a novel experimental technique was used. Tree saplings with complete structural root systems …

Enhancing The Seismic Performance Of Steel Structures Utilizing Superelastic Shape Memory Alloys, Papia Sultana

Electronic Thesis and Dissertation Repository

Although conventional earthquake-resisting structural systems provide the life safety level during earthquakes, they experience significant structural damage when exposed to strong ground shaking that render structural retrofitting as uneconomical. Superelastic shape memory alloys (SMAs) can be used in steel structures to reduce the residual deformations due to their recentering capability, which can facilitate post-seismic retrofitting. The primary aim of this thesis is to enhance the seismic performance of both regular and modular steel structures using an optimum amount of superelastic SMAs material in terms of maximum inter-storey drift, residual drift, and damage scheme.

First, a simplified method based on pushover …

Evapotranspiration From Extensive Green Roofs: Influence Of Climatological Conditions, Vegetation Type, And Substrate Depth, Maria Eloisa Sia

Electronic Thesis and Dissertation Repository

Green roofs are gaining popularity worldwide as a low impact development tool to mitigate increasing stormwater runoff within dense urban areas. Evapotranspiration (ET) is the key hydrologic process governing the capacity of a green roof to retain rainfall as it regenerates available water storage space in the green roof substrate (soil) between rainfall events. To date, there are limited data on how the interaction between different climatological conditions and design parameters (e.g., vegetation type, substrate depth) affect ET rates. This currently limits the ability to optimize green roof design for stormwater management. In this field study, the impact of climatological …

Numerical Studies For Improving Fracture Toughness Resistance Curve Testing Using Single-Edge (Notched) Tension Specimens, Yifan Huang

Electronic Thesis and Dissertation Repository

The fracture toughness resistance curve, i.e. the J-integral resistance curve (J-R curve) or the crack tip opening displacement resistance (CTOD-R) curves, is widely used in the integrity assessment and strain-based design of energy pipelines with respect to planar defects (i.e. cracks). This thesis deals with issues related to the experimental determination of the J(CTOD)-R curves using the newly-developed single-edge (notched) tension (SE(T)) specimens. In the first study, the plastic geometry factor, i.e. the η_pl factor, used to evaluate J in a J-R curve test based on …

Anaerobic Digestion And Co-Digestion Of Thickened Waste Activated Sludge (Twas) And Food Waste (Fw), Mohammad M I Chowdhury

Electronic Thesis and Dissertation Repository

This study aimed at assessing the impact of ultrasonication on the anaerobic digestibility of thickened waste activated sludge (TWAS) in anaerobic fluidized bed reactor (AnFBR), determining the unbiodegradable fraction of TWAS, and exploring co-digestion of food waste (FW) and TWAS. Two lab-scale AnFBRs treating TWAS were studied to explore the impact of ultrasonication (US) in the break down and reuse of scum for methane production. At an organic loading rate (OLR) of 4.7 kg COD/m³-d and 480 kJ of US energy, COD and VSS destruction efficiencies were 65% and 63%, respectively roughly 20% higher than the control reactor …

Innovating Two-Stage Concrete With Improved Rheological, Mechanical And Durability Properties, Manal F. Najjar

Electronic Thesis and Dissertation Repository

Two-stage concrete (TSC), also known as preplaced aggregate concrete, is a special type of concrete that is produced using a unique procedure which differs from that of conventional concrete. TSC is distinguished by its high coarse aggregate content and exceptional placement technique, whereby aggregates are first pre-placed in the mold then injected with a special grout. The preplacement of aggregates saves substantial energy since only the grout needs mechanical mixing; the grout is self-leveling and needs no vibration and no mechanical compaction. However, TSC applications are still limited despite substantial advancement of modern concrete technology. Therefore, there is a need …

Starx Technology For Waste Oil Sludge Treatment Investigated With Numerical Modelling, Rebecca L. Solinger

Electronic Thesis and Dissertation Repository

Growing stockpiles of industrial liquid waste stored in lagoons are an outstanding problem worldwide. Self-sustaining Treatment for Active Remediation (STAR) is an emerging technology based on smouldering combustion that has been successfully deployed for in situ remediation of field sites (Grant et al., 2016). STAR is currently being developed as an ex situ treatment system (STARx) for industrial wastes by intentionally mixing them with sand. One engineering concept for STARx is the “hotpad”, for which some initial experiments have been conducted. However, a thorough experimental investigation is challenging due to the cost and time associated with each experiment. This work …

Hydraulic And Electrokinetic Delivery Of Remediants For In-Situ Remediation, Ahmed I. A. Chowdhury

Electronic Thesis and Dissertation Repository

Nano-scale zero valent iron (nZVI) has shown promising mobility and in-situ reactivity with chlorinated volatile organic compounds when injected into saturated porous media. The current study evaluated nZVI mobility and subsequent reactivity with in-situ contaminants in a variably saturated porous media. The nZVI particles, synthesized onsite at subzero temperatures, demonstrated complete trichloroethene (TCE) degradation within the target area. Furthermore, a three dimensional finite difference model (CompSim) was utilized to investigate nZVI mobility in variably saturated zones. Model predicted well head data were in very good agreement with field observations. Simulation results showed that the injected slurry migrated radially outward from …

Estimation Of Wind Hazard Over Canada And Reliability-Based Assignment Of Design Wind Load, Qian Tang

Electronic Thesis and Dissertation Repository

The current National Building Code of Canada (NBCC) recommends a wind load factor of 1.4 and the nominal wind velocity pressure corresponding to 50-year return period value of the annual maximum hourly-mean wind speed, V_AH. This study is focused on mapping wind hazard for Canada and on calibrating the required design wind load to improve reliability consistency of the designed structures.

Extreme value analysis of V_AH was carried out by considering surface wind observations from approximately 1300 stations. The results indicate that the spatial trends of the estimated mean of V_AH are similar whether the data …

Removal Of Target Ppcps From Secondary Effluent Using Aops And Novel Adsorbents, Venkateswara Reddy Kandlakuti

Electronic Thesis and Dissertation Repository

Atenolol (β-blocker), Clofibric Acid (Lipid regulators) and Diclofenac (Anti-inflammatory) are the drugs widely used and reported to have adverse effects on fish and other organisms. These drugs are found at trace levels in lakes, rivers and sewage treatment plants and conventional treatment plants are ineffective to eliminate these at those levels. A high resolution LC-MS/MS was used to quantify these drugs at low levels. Various advanced oxidation methods were used for the present research to eliminate these drugs from secondary effluent. Complete removal of PPCPs was achieved by synthesizing immobilized TiO2 on a stainless steel mesh and using a combination …

Soil Aquifer Treatment For Wastewater Reclamation In A High Water Demand Society, Diego J. Velasquez

Electronic Thesis and Dissertation Repository

Water resources around the world are under increasing pressure from the rapidly growing demands of rising population and industrialization. Furthermore, changes in global weather patterns are expected to intensify its current and future stresses. In the present study, knowledge and perceptions towards wastewater reclamation for potable and non-potable uses were investigated by the used of an on-line survey distributed amongst the university community at Western university. Subsequent statistical analysis of the results was performed using IBM-SPSS software. Survey results show that member of the university community are more likely to accept reclaimed wastewater for applications that do not involve drinking …

Time-Dependent Behaviour Of Micro-Tunneling Construction In Queenston Shale, Hayder Mohammed Salim Al-Maamori

Electronic Thesis and Dissertation Repository

The Queenston shale among other shales from southern Ontario exhibits time-dependent deformation behaviour. This behaviour is manifested in the form of volume increase which can cause damages to the hosted underground structures. The time-dependent deformation of rocks can cause cracks in the springline of tunnels, wall inward movement, roof spalling and floor heave, which requires costly remedial measures. The expansion of the existing infrastructures in southern Ontario requires construction techniques, such as micro-tunneling to build new tunnels and pipelines under the existing structures with minimal impact to these structures and to the environment. However, adopting this technique in swelling rocks, …

Evaluation Of Voc Degradation In Photo-Catalytic Air Reactors: Tio2 Immobilization, Energy Efficiency And Kinetic Modeling, Cristina S. Lugo Vega

Electronic Thesis and Dissertation Repository

The high VOC emissions from anthropogenic sources are detrimental to both the environment and humans, contributing with ground-level ozone and particle matter formation. Heterogeneous photocatalysis provides significant potential for VOC degradation. However, the approaches to be used for photocatalyst immobilization in scaled and highly efficient photoreactors are still not well established. Furthermore, there is a lack of reported photonic efficiencies and a shortage of required methods to establish these efficiencies.

To address these issues, this PhD Dissertation reports the study of photonic efficiencies, TiO₂ immobilization on a stainless steel mesh and kinetic models in a scaled-up Photo-CREC-Air Reactor. Acetone …

Automated Control Flaw Generation Procedure: Cheakamus Dam Case Study, Bogdan Pavlovic

Electronic Thesis and Dissertation Repository

This thesis deals with the problem of aging hydropower infrastructure systems and system components, a problem that is very common across Canada. Flaws of common risk analysis methods are noted, and the need for new risk analysis approaches is identified. System dynamics simulation method is introduced as an implementation mechanism for the System Theoretic Process Analysis (STPA). STPA and its adaptation to complex hydropower systems are explained thoroughly. Fuzzy logic is used to model operator’s decision making. The main objectives of the research include the development of an automated generic approach that implements STPA and fuzzy logic for the investigation …

Catalytic Conversion Of Fructose, Glucose And Industrial Grade Sugar Syrups To 5-Hydroxymethylfurfural, A Platform For Fuels And Chemicals, Sadra Souzanchi

Electronic Thesis and Dissertation Repository

5-hydroxymethylfurfural (HMF) as a versatile and polyfunctional compound derived from dehydration of biomass has attracted increasing attentions in research over the past decades. HMF is an important intermediate and platform chemical, which can be converted into different useful chemicals as well as the promising biofuels. It can be obtained from acid-catalyzed dehydration of different C₆-based carbohydrates such as glucose, fructose, sucrose and cellulose.

In this thesis, a cost-effective process for catalytic conversion of simple sugars (particularly glucose and fructose) and industrial grade sugar syrups to HMF was studied in a novel biphasic continuous-flow tubular reactor using inexpensive heterogeneous …

Hydrothermal Liquefaction Of High-Water Content Biomass And Waste Materials For The Production Of Biogas And Bio-Crude Oil, Laleh Nazari

Electronic Thesis and Dissertation Repository

Growing interest in renewable energies due to shrinking reserves of fossil fuels and climate change concerns have led to extensive research towards gaseous and liquid fuels production from renewable energy resources such as biomass and wastes. Energy generation from municipal and industrial wastes such as wastewater sludge is also environmental friendly way to deal with large volume of waste disposal with the additional advantage of eliminating part of the indirect greenhouse gas emissions from energy crops-derived biofuels.

In this thesis, a novel process for co-production of biogas and bio-crude oil from high-water-content wastewater sludge through hydrothermal liquefaction (HTL) treatments is …

Short-Term Deflections Of Reinforced Concrete Beams, Caitlin Mancuso

Electronic Thesis and Dissertation Repository

Excessive deflection of concrete beams is a recurring serviceability problem. Provisions in current building codes, CSA A23.3-14 and ACI 318-14, account for some but not all of the contributing factors. The effect of loading concrete members at very young ages on the associated deflections remains uncertain.

Concrete stress-strain data reported by others are used to investigate if conventional stress-strain relationships, and empirical equations in A23.3-14 for tensile strength and elastic modulus are accurate for young concretes. Moment-curvature analyses based on conventional simplifying approximations used for flexural analysis are performed. For concretes less than one day old, the conventional relationships and …

Electrokinetics And Vacuum Combined Dewatering Of Oil Sand Tailings, Rui Zhang

Electronic Thesis and Dissertation Repository

One of the challenges faced by the oil sand industry is the dewatering of mature fine oil sands tailings (MFT) due to the low permeability. Vacuum pressure or electrokinetic (EK) dewatering is effective to meet this objective. This research was focused on the experimental study and analytical modelling to explore the influence of combined vacuum and EK treatment on MFT. In this study, systematical experiments on MFT recovered from the northern Alberta were carried out. At first, the characterization and EK cell tests were conducted to measure the basic properties and the coefficient of electroosmotic permeability (ke) of MFT. Secondly, …

Identification Of Groundwater Discharge Along The Shoreline Of Large Inland Lakes In Southern Ontario, Tao Ji

Electronic Thesis and Dissertation Repository

Groundwater discharge may be an important pathway for delivering pollutants into nearshore waters of large inland lakes, including the Great Lakes and Lake Simcoe in Southern Ontario, Canada. This pathway however is poorly understood and quantified. While field methods for evaluating groundwater discharge to surface waters in tributary and marine settings have been widely applied and are well tested, there are limited field methods available for evaluating groundwater discharge to large inland lakes, particularly at the regional scale (i.e. 5-100 km). The objective of this thesis was to evaluate suitable field methods for quantifying groundwater discharge into large inland lakes …

Mat-705: Improving The Efficiency Of Zinc Sacrificial Anodes In Repaired Concrete, Ahmed G. Bediwy, Mohamed T. Bassuoni, Martin Beaudette

Canadian Society for Civil Engineering

Zinc sacrificial anodes are considered an effective and economical method to prevent the electrochemical corrosion of steel bars by providing cathodic current to bars, which can provide corrosion protection at low galvanic current densities in the range of 0.2 to 2 mA/m2. Sacrificial anodes are commonly used in RC structures particularly in bridge decks to mitigate a critical phenomenon that occurs in the original concrete beside the repaired patches, which is known as the ‘halo effect’. One of the key factors affecting the efficacy of zinc anodes is the resistivity of concrete or cementitious repair material in which these anodes …

Mat-701: Predicting The Compressive Strength Of Ultra-Lightweight Concrete By An Artificial Neural Network, Jordan Ouellet, Jean-Luc Martel, Claudiane Ouellet-Plamondon, Alan Carter

Canadian Society for Civil Engineering

Ultra-lightweight concrete (ULWC) has potential applications for floating structures and architectural elements because of its dry density coming in at under 1000 kg/m3. The objective was to develop an artificial neural network (ANN) to aid the ULWC designer according to his needs. Boundary conditions were set for each material and 13 constraints based on the water binder ratio, density, air content, binder and aggregate content. The ANN predicted the compressive strength with a comfortable margin of error, with the gap encountered being attributed to variability in workability. Precise constraints and boundary conditions are needed to ensure a lower variability in …