Engineering Commons^™

Applying Probabilistic Methods To The Nato Military Load Classification System For Bridges, Andrew J. Macdonald

Electronic Thesis and Dissertation Repository

Military vehicles frequently use civilian bridges. The loading effects of military vehicles, both wheeled and tracked, are specific and different than those of civilian vehicles in normal traffic. Calibration to determine appropriate load factors for military loading of civilian bridges has not been fully performed and the corresponding levels of safety have not been quantified. This lack of calibration prevents the implementation of limit state design methods for military bridges and the evaluation bridges for military loading. This thesis quantifies probabilistically the single lane traffic load effects on interior girders of simply supported slab-on-girder bridges for three military vehicles in …

Wind And Thermal Effects On Ground Mounted Photovoltaic (Pv) Panels, Chowdhury Mohammad Jubayer

Electronic Thesis and Dissertation Repository

A combination of Computational Fluid Dynamics (CFD) simulations and wind tunnel experiments are carried out to investigate the effects of wind on the aerodynamic loading and heat transfer of a ground mounted stand-alone photovoltaic (PV) panel with tilt angle of 25^o in open country atmospheric boundary layer. Several azimuthal wind directions are considered: Southern 0^o, Southwest 45^o, Northwest 135^o and Northern 180^o. Three dimensional Reynolds-Averaged Navier-Stokes (RANS) approaches with an unsteady solver using Shear Stress Transport (SST) k-ω turbulence closure are employed for the CFD simulations, whereas Particle Image Velocimetry (PIV) and …

Treatment Of Synthetic Oil Sands Tailing Water With Activated Carbon, Alfredo Martinez Iglesias

Electronic Thesis and Dissertation Repository

The extraction of bitumen from the Canadian tar sands has thus far generated approximately 840 billion liters of oil sands process affected water (OSPW) that is currently being stored in containment ponds. OSPW is known to be acutely toxic to various organisms, due to the presence of naphthenic acids (NAs). The scale and sheer volume of OSPW being stored in tailing ponds have generated serious public concerns. Many emerging technologies have been investigated as treatment options for OSPW reclamation. This work studied the feasibility of using granular activated carbon (GAC) to adsorb several naphthenic acids in a model solution of …

Scale-Up Methodology For Bench-Scale Slurry Photocatalytic Reactors Using Combined Irradiation And Kinetic Modelling, Patricio J. Valades Pelayo

Electronic Thesis and Dissertation Repository

The present study focuses on developing a predictive methodology to scale-up a slurry annular photoreactor using a TiO₂ Degussa P25 from the bench-scale to a pilot-plant scale. The bench-scale photoreactor is a Photo-CREC-Water II, a 2.65 L internally-irradiated slurry annular photocatalytic reactor. The pilot-plant scale photoreactor is a Photo-CREC Water Solar Simulator, a 9.8 L pilot-plant photoreactor, externally irradiated by eight lamps.

The adopted methodology allows the independent validation of radiative and kinetic models avoiding cross-correlation issues. The proposed approach involves two Monte Carlo methods, to model the Radiative Transfer Equation (RTE) inside each photoreactor. With this end, a …

Enhanced Dechlorination Of 1,2-Dichloroethane By Coupled Nano Iron-Dithionite Treatment, Ariel Nunez Garcia

Electronic Thesis and Dissertation Repository

1,2-dichloroethane (1,2-DCA) is a chlorinated solvent classified as a probable human carcinogen. Due to its extensive industrial applications, widespread contamination and recalcitrance towards abiotic dechlorination, 1,2-DCA remains a challenging compound for the remediation community and one of the great research interests. Batch experiments combining bimetallic or monometallic nZVI (stabilized or non-stabilized) with sodium dithionite were conducted for the degradation of 1,2-DCA. These experiments have yielded up to 92 % degradation of the initial 1,2-DCA concentration over the course of a year. Observed pseudo-first order rate constants (k_obs) range from 3.8 x 10^-3 to 7.8 x 10^{-3 …}

Influence Of Water Chemistry Parameters On The Dissolution Rate Of The Lead (Ii) Carbonate Hydrocerussite, Caitlin Se Kushnir

Electronic Thesis and Dissertation Repository

This work has focused on the kinetic dissolution of the lead (II) carbonate hydrocerussite (Pb₃(CO₃)₂(OH)₂) under four pH conditions (7.5, 8, 9, 10), three dissolved inorganic concentrations (DIC; 10, 20, 50 mg C/L), and three initial hydrocerussite concentrations (10, 20, 50 mg/L) in batch experiments. Experiments were performed in at least duplicate to determine total dissolved lead dissolution curves at short time scales (hr.). All equilibrium dissolved lead concentrations were achieved in 40 minutes or less, and matched trends from previous studies; pH 7.5 and pH 10 corresponding to the highest and …

Miniature Cone Penetration Test On Loose Sand, Sepideh Damavandinejad Monfared

Electronic Thesis and Dissertation Repository

Considering the difficulties associated with preparing loose sand samples in large calibration chambers and wide area of research on the behavior of loose sands, miniature calibration chamber experiments are used to perform cone penetration tests on soils in different states. A miniature cone calibration chamber has been designed and developed in this study. Nineteen tests have been performed on Ottawa sand and the results are compared to the available data in the literature. The accuracy of the results is validated by comparing the results with the suggested rate for the cone resistance in sands in literature. More specifically, results are …

Performance Of Micropiled Raft In Sand And Clay-Centrifuge And Numerical Studies, Ahmed M. Alnuaim

Electronic Thesis and Dissertation Repository

A micropile is a small diameter “cast-in-place” pile, which was initially used to repair deficient foundations. The overall performance of a micropiled raft (MPR) foundation system is similar to a piled raft foundation where the load is transmitted through both the raft and the micropiles. This thesis explores using micropiled rafts (MPR) as a new highly efficient foundation system that combines the advantages of the piled raft system and the efficient installation of micropiles and associated ground improvement. Currently, there is no guidance available regarding the performance of MPR foundations. Therefore, the main objectives of this research are to evaluate …

Thickening Of Mature Fine Oil Sands Tailings, Shriful Islam

Electronic Thesis and Dissertation Repository

The mature fine oil sands tailings (MFT) remain suspended in tailings disposal pond for decades because of the low sedimentation/consolidation rate. This study investigates the application of coagulation and electrokinetics to thicken, i.e., to increase the solid content of the MFT suspension. At first, the optimal ferric chloride concentration is identified as 350 mg/l in jar tests, under which the best thickening result is only 6.48% from an initial of 5% after 4 hours in cylinder coagulation tests. The electrokinetic thickening under an applied voltage gradient of 219 V/m reaches the final solid content of 18.75% after 7 hours. The …

Contribution Of Gypsum-Board Sheathing To The Compressive Resistance Of Wood Studs Subjected To Gravitational Loads, Daniel J. Grenier

Electronic Thesis and Dissertation Repository

Gypsum board is the most commonly used sheathing material in Canadian residential construction. Current Canadian standards recognize the role of gypsum-board sheathing in bracing studs to prevent weak-axis buckling and in resisting in-plane shear, but do not recognize its potential contribution to axial compressive resistance of a sheathed wall. The research in this thesis, therefore, investigates this contribution for light-frame wood stud walls sheathed with gypsum-board on both sides of the stud. The axial compressive resistance of bare and gypsum-board sheathed studs were computed using new finite element models that account for the nonlinear wood stress-strain relationship and nonlinear shear …

Numerical And Experimental Studies Of Transmission Lines Subjected To Tornadoes, Ahmed Hamada

Electronic Thesis and Dissertation Repository

The majority of worldwide weather-related transmission line failures have been attributed to High Intensity Wind (HIW) events in the form of tornadoes and downbursts. The research conducted in the current thesis presents a significant development in the understanding of the structural behaviour of transmission line systems under tornado loading. A comprehensive in-house numerical model that combines the data of computational fluid dynamic (CFD) simulations of tornado wind fields with three dimensional nonlinear structural analysis modelling is developed. A three dimensional four-nodded cable element is first formulated to simulate the nonlinear large deformation behaviour of the conductors. The support provided to …

Investigation Of Fracture Toughness Measurement For Pipeline Steels Based On Se(B) And Se(T) Specimens, Zijian Yan

Electronic Thesis and Dissertation Repository

This thesis deals with issues related to the experimental determination of the fracture toughness resistance curves, i.e. the J-integral (J)-R curve and crack tip opening displacement (CTOD)-R curves, using the single-edge bend (SE(B)) and single-edge tension (SE(T)) specimens. First, the impact of the crack front curvature on the J-R curve measured from the SE(B) specimen is investigated through systematic linear-elastic and elastic-plastic three-dimensional (3D) finite element analyses (FEA) of SE(B) specimens containing both straight and curved crack fronts. Three average relative crack lengths are considered, namely 0.3, 0.5 and 0.7, and three specimen width-to-thickness ratios are …

Probabilistic Modeling And Bayesian Inference Of Metal-Loss Corrosion With Application In Reliability Analysis For Energy Pipelines, Hao Qin

Electronic Thesis and Dissertation Repository

The stochastic process-based models are developed to characterize the generation and growth of metal-loss corrosion defects on oil and gas steel pipelines. The generation of corrosion defects over time is characterized by the non-homogenous Poisson process, and the growth of depths of individual defects is modeled by the non-homogenous gamma process (NHGP). The defect generation and growth models are formulated in a hierarchical Bayesian framework, whereby the parameters of the models are evaluated from the in-line inspection (ILI) data through the Bayesian updating by accounting for the probability of detection (POD) and measurement errors associated with the ILI data. The …

Wind-Induced Pressures In Air Permeable, Double-Layer Roof Systems In Regions Of Separated Flow, Jeong Hee Oh

Electronic Thesis and Dissertation Repository

This thesis is concerned with the wind-induced pressure distribution acting on air permeable, double-layer roof systems placed on low-rise buildings. Because of the pressure transmission into the cavity between layers, the pressure difference in the double-layer systems differs significantly from that in a single layer. The interior pressures (in the cavity between layers) are highly correlated with external pressures at the openings on the external surface of the outer layer and thereby, the net wind load for the design of the outer layer is considerably reduced by the pressure equalization between the external and internal surfaces of the outer layer. …

Response Of Transmission Line Conductors Under Downburst Wind, Haitham Aboshosha

Electronic Thesis and Dissertation Repository

Electricity is transmitted by Transmission Lines (TLs) from the source of production to the distribution system and then to the end consumers. Failure of a TL can lead to significant economic losses and to negative social consequences resulting from the interruption of power. High Intensity Winds (HIW), in the form of downbursts and tornadoes, are believed to be responsible for more than 80% of the weather-related failure of TLs around the world. The studies reported in this thesis are part of an ongoing extensive research program at Western University focusing on the response of TLs under HIW. Previous investigations conducted …

Solid-Phase Extraction As Sample Preparation For Bioassay-Based Micropollutant Quantification, Chen Feng

Electronic Thesis and Dissertation Repository

Solid phase extraction (SPE) using chemically bonded silica particles or small particles of an organic polymer resin, is being studied extensively for extraction of polar or non-polar compounds from various water matrices. This study focused on the evaluation of the performance of three commercial cartridges belonging to three different groups: reversed-phase, mixed-mode anion exchanger and mixed-mode cation exchanger. In the first stage of research, the performance of three cartridges was compared by extracting four antibiotics with different physic-chemical properties from water samples. The results obtained from column sorption experiments were plotted into breakthrough curves and batch equilibrium experiments results were …

Characterization Of The Green Roof Growth Media, Ginevra Alessandra Perelli

Electronic Thesis and Dissertation Repository

Green roofs are becoming a popular solution to manage the stormwater, to reduce the energy consumption in highly urbanized environment and provide many additional benefits. One of the key components that characterize the green roof system is the growth medium; the medium supports the plants, providing water and nutrient storage, and contributes to the roof insulation.

The object of this thesis is to investigate the hydraulic and the thermal properties of the green roof growth medium and to study the relationship among these properties through extensive laboratory analyses. In addition, the laboratory results are compared with direct measurements in the …

Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta

Electronic Thesis and Dissertation Repository

The aim of this study was to assess the synergistic effects of co-fermentation of glucose, starch, and cellulose using anaerobic digester sludge (ADS) on the biohydrogen (H₂) production and the associated microbial communities. At initial pH of 5.5 and mesophilic temperature of 37 ºC, the H₂ yields were greater by an average of 27 ± 4% in all the different co-substrate conditions compared to the mono-substrate conditions, which affirmed that co-fermentation of different substrates improved the hydrogen potential. The sensitivity of mesophilic ADS to a temperature shock was also investigated. Unacclimatized mesophilic ADS responded well to a …

Biostimulation Of Oil Refinery Soils, Thipphathong Vattaso

Electronic Thesis and Dissertation Repository

Oil refinery contaminated soils usually contain carcinogenic products, including polycyclic aromatic hydrocarbons (PAHs), and therefore require treatment for environmental and human protection. Biostimulation is the modification of external factors affecting the performance of indigenous bacteria and it may be employed to enhance natural attenuation at contaminated sites. Contaminated soil samples, provided by Imperial Oil (Sarnia, Ontario), were analyzed using pyrosequencing to sequence DNA strains in order to identify types of bacterial genus found in the samples. Flavobactericeae and Marinobacter were the two most dominant genus found in the sample, both recorded with the ability to degrade PAHs.

Favourable conditions and …

Electrical Resistivity Tomography For Mapping Subsurface Remediation, Christopher Power

Electronic Thesis and Dissertation Repository

Cleaning up sites contaminated with dense non-aqueous phase liquids (DNAPLs) remains a challenging geoenvironmental problem. The performance of site remediation methods is difficult to assess without a practical, non-destructive technique to map where and how quickly DNAPL mass is being reduced. The promise of electrical resistivity tomography (ERT) in this context has not been realized, in part because traditional ERT methods were used to solve the near-impossible problem of mapping the initial DNAPL outline. However, new developments in ERT have emerged that focus on resolving subsurface changes over time. The objective of this work was to evaluate the potential of …

Physical Sulphate Attack On Concrete, Ahmed Ramadan Suleiman

Electronic Thesis and Dissertation Repository

Field experience with concrete exposed to sulphates has often shown that concrete can suffer from surface scaling above the ground level caused by physical sulphate attack. This type of attack has been ignored and, in some instances, confused with chemical sulphate attack. In addition, current standards that evaluate the performance of concrete under sulphate attack, only deal with the chemical aspects of sulphate attack. This lack of information has led to confusion and contradictory views regarding the mechanisms of concrete deterioration due to physical sulphate attack. In the current thesis, the performance of concrete exposed to environments prone to physical …

Full-Scale Tests Of A Wood-Frame Structure Under Extreme Wind Loads, Derek A. Stedman

Electronic Thesis and Dissertation Repository

Tornadoes can produce some of the strongest winds on earth; these highly localized storms can cause massive damage. Assessments of tornado wind speeds are done using post-event observations of damage via the Enhanced Fujita Scale.

A very commonly observed failure occurs at the roof-to-wall connection where the roof breaks up or flies away, typically leaving the walls in place. However, once the roof is gone the walls are more vulnerable to the wind. If a wall subsequently fails, it increases the risk of injury or death for occupants. Significant research has been done for failures of roof-to-wall connections and roof …

Development Of Probabilistic Corrosion Growth Models With Applications In Integrity Management Of Pipelines, Shenwei Zhang

Electronic Thesis and Dissertation Repository

Metal-loss corrosion is a major threat to the structural integrity and safe operation of underground oil and gas pipelines worldwide. The reliability-based corrosion management program has been increasingly used in the pipeline industry, which typically includes three tasks, namely periodic high-resolution inline inspections (ILIs) to detect and size corrosion defects on a given pipeline, engineering critical assessment of the corrosion defects reported by the inspection tool and mitigation of defects. This study addresses the core involved in the reliability-based corrosion management program. First, the stochastic process in conjunction with the hierarchical Bayesian methodology is used to characterize the growth of …

Mechanism Of Dissolution Of High Valence Lead Oxides In Water Under Depleting Chlorine Conditions, Daoping Guo

Electronic Thesis and Dissertation Repository

Destabilization of lead corrosion scales present in plumbing materials used in water distribution systems results in elevated lead concentrations in drinking water. Lead release caused by changes in water chemistry (e.g., redox conditions) is often due to the destabilization of lead carbonate and oxide solid phases. Although prior studies have examined the effects of varying water chemistry on the stability of β-PbO₂ (plattnerite), β-PbO₂ stability under depleting chlorine conditions is poorly understood. In addition little is known regarding the mechanisms by which Pb₃O₄ (minium) dissolves under drinking water conditions. In this thesis, long-term batch dissolution …

Static And Seismic Performance Of Geosynthetics-Strengthened Pile Foundations, Ahmed M. Taha

Electronic Thesis and Dissertation Repository

Geosynthetic reinforcement in earth structures has been used extensively over the last two decades. Extensive research has been carried out to investigate solutions to enhance the lateral stability of pile foundations. This research is motivated by the need to install piles in sites characterized by soft subsurface soil conditions, and often times, in seismic active areas. This research work explores an innovative use of geosynthetics to enhance the lateral performance of pile foundations. The static and seismic soil-structure-interaction behaviors of geosynthetics-reinforced pile foundation systems were evaluated using a series of reduced scale physical model tests performed on a shaking table …

Behaviour Of Reinforced Concrete Conical Tanks Under Hydrostatic Loading, Tareq M. Azabi

Electronic Thesis and Dissertation Repository

Reinforced concrete conical tanks are used in municipalities and industrial applications as liquid containing vessels. Such tanks can be ground supported tanks or elevated on a supporting shaft. Although most design codes provide guidelines for rectangular and cylindrical tanks, no guidance is provided in such codes for conical tanks. Therefore, this thesis is motivated to study the behaviour and design of this type of tanks. In the current study, the accuracy of a design approach based on the provisions of Portland Cement Association (PCA-CCTWP) code for cylindrical tanks combined with an equivalent cylindrical approach provided by the American Water Works …

Shear Capacity Of Reinforced Concrete Beams At Elevated Temperatures, Mohamed Diab

Electronic Thesis and Dissertation Repository

Fire safety is an important design aspect that ensures structural integrity of a Reinforced Concrete (RC) building during fire events. As new codes are moving from prescriptive methods to performance-based methods, design engineers are in need of rational design tools to assess the capacity of RC elements during a fire event. Previous research work focused on the flexural and axial capacities of concrete elements exposed to fire. Research addressing the shear capacity of concrete elements exposed to fire is limited in the literature.

An analytical method to predict the shear capacity of RC beams exposed to elevated temperatures is proposed. …

Structural And Durability Performance Of Precast Segmental Tunnel Linings, Safeer Abbas

Electronic Thesis and Dissertation Repository

The use of precast concrete tunnel linings (PCTLs) has been escalating due to its efficient and economical installation process compared to that of normal cast in-situ lining practice. Normally, PCTL segments are designed for 100 years of service life. However, tunnel structures often suffer premature degradation primarily due to reinforcement corrosion, which requires costly repair and maintenance. Hence, addressing and solving such durability-sustainability dilemma of tunnels is a must. The main aim of this dissertation is to evaluate the structural and durability performance of full-scale conventional reinforced concrete (RC) PCTL segments in comparison to steel fibre-reinforced concrete (SFRC). Moreover, the …

Removal And Recovery Of Heavy Metals By Nickel Smelter Slag, Maame Kyeiwaa Addai

Electronic Thesis and Dissertation Repository

The research was performed to assess the potential of nickel smelter slag, an industrial waste, as an adsorbent in the removal of heavy metals from solution. Results from batch studies on the effect of pH, metal-slag contact time, particle size, competition by other ions and slag dose were used to estimate the optimum adsorption conditions of the slag as an adsorbent for Cu, Pb, Cd, Ni and Zn. Adsorption of Cu and Pb were akin to the pseudo second order kinetic model and followed the Langmuir adsorption isotherm model. The calculated k₂ values were 0.18 mg g^-1min …