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Free Surface Confinement Effects On A Round Jet, Jiahao Tian
Free Surface Confinement Effects On A Round Jet, Jiahao Tian
Electronic Theses and Dissertations
In this study, the characteristics of a round turbulent jet in the vicinity of a free surface are investigated. The results reveal that the velocity normal to the free surface is diminished, and the velocity components parallel to the free surface are enhanced in the region near the free surface. The magnitude of shear stress in the vertical central plane of the surface jet is smaller than that noticed in the free jet near the free surface, while the magnitudes of profiles are larger compared to that of the free jet. A higher magnitude of the vorticity is observed in …
Reliability Of Serviceability And Strength Of Deep Foundations Embedded In (P-Y) Sand Below Water Table Subjected To Lateral Cyclic Loading, Ruoah Yousif
Electronic Theses and Dissertations
Piles are used in many engineering applications especially when we have weak soil that cannot support the proposed structure, also when we have a scour issue with the soil (especially in designing foundations for bridges), or when large uplift capacity is needed. In many engineering applications the piles are subjected to lateral loads as well as axial loads. Many design variables (uncertainties) affect the behavior of laterally loaded piles and the pile-soil system and their modeling. In reality when engineers are faced with uncertainties, they use a factor of safety to design the structure or a component, which is a …
Behaviour Of Corroded X46 Steel Pipe Under Internal Pressure And Axial Load, Halima Dewanbabee
Behaviour Of Corroded X46 Steel Pipe Under Internal Pressure And Axial Load, Halima Dewanbabee
Electronic Theses and Dissertations
Corrosion is a major cause for buried gas pipeline failure. Current design guidelines are limited to pressure loading for assessing corroded pipeline's integrity. A few studies were conducted by other researchers to determine the remaining bending or pressure strength of the corroded pipelines under combined loading. No study was conducted to determine the axial compressive strength of the corroded pipelines although it could be the major cause of pipeline failure. Therefore, the current study was completed using full-scale tests and a parametric study using FEA to assess the integrity of X46 corroded pipe subjected to severe axial compression and internal …
Shallow Wake In Open Channel Flow - A Look Into The Vertical Variability, Arindam Singha
Shallow Wake In Open Channel Flow - A Look Into The Vertical Variability, Arindam Singha
Electronic Theses and Dissertations
The vertical variability of a typical wake behind a bluff body in an open channel flow has been investigated. The focus of the study was to explore the variability of the flow structures in terms of mean velocity profiles, turbulent parameters and coherent structures in the vertical direction. A sharp-edged bluff body was chosen to minimize the effect of Reynolds number and ensure fixed flow separation points in the vertical direction. Velocity measurement was performed by Particle Image Velocimetry at three vertical locations: near-bed, mid-depth and near the free surface. In the streamwise direction, three different fields-of-view are taken to …
Effect Of Drinking Water Ozone Treatment On Select Pharmaceuticals And Personal Care Products (Ppcps) And Endocrine Disrupting Compounds (Edcs), Chaoyang Yue
Electronic Theses and Dissertations
The effect of five process variables on the transformation of 16 selected PPCP/EDCs during drinking water ozonation was systematically studied through 25-1 fractional factorial designed experiments. Dissolved Organic Carbon (DOC) content, ozone dose, and their interaction were most significant for all 16 compounds, and accounted for 60-98 of the observed variability in the transformation efficiencies. Temperature was a significant factor for most of the fast-reacting compounds (kO3 >10 4 M-1s-1), accounting for up to 20 of the change in transformation efficiency, but was not significant for the slow-reacting compounds (kO3 -1s-1). Ozone exposure of > 1.0 mg L'-1' min-1 resulted in …
Repair Of Corroded Steel Beam Using Cfrp, Meiling Chen
Repair Of Corroded Steel Beam Using Cfrp, Meiling Chen
Electronic Theses and Dissertations
Many steel structures were built during World War I and II. More than twenty percent of steel bridges in the USA are structurally deficient. The cost for rehabilitation in most cases is far less than the cost of replacement. Moreover, the rehabilitation generally takes less time than replacement. Due to the limited methods available to mitigate this problem, new materials were explored in recent years to adopt cost-effective technique to address this issue. This thesis focuses on the use of Carbon Fiber Reinforced Polymer (CFRP) sheets as a competitive technique to restore the capacity of surface corroded steel beam. Rehabilitation …
Photocatalytic Degradation Of Select Drinking Water Pollutants Using Nano-Titanium Dioxide Catalyst, Marissa Labbe
Photocatalytic Degradation Of Select Drinking Water Pollutants Using Nano-Titanium Dioxide Catalyst, Marissa Labbe
Electronic Theses and Dissertations
Advanced oxidation processes, such as photocatalysis, are attractive water treatment options in which the generation of a strong oxidizing species, the hydroxyl radical (•OH), is responsible for the mineralization of pollutants bearing reduced carbons. This work aims to assess the photocatalytic degradation of phenolic compounds in the presence of titanium dioxide (TiO 2) nanoparticles (in aqueous) and UV light. Individual and combined effects of experimental variables such as TiO2 particle size (5, 10 and 32 nm), temperature (23, 30 and 37C) and reactant type (phenol, o-cresol, m-cresol) on the apparent degradation rate constant was determined. The largest photocatalytic activity was …
Non-Linear Analysis Of Concrete Beams Prestressed And Post-Tensioned With Carbon Fiber Reinforced Polymer (Cfrp) Bars., Mohamad Fathy Abd El Aziz
Non-Linear Analysis Of Concrete Beams Prestressed And Post-Tensioned With Carbon Fiber Reinforced Polymer (Cfrp) Bars., Mohamad Fathy Abd El Aziz
Electronic Theses and Dissertations
The deterioration of concrete bridges has been a major concern for structural engineers especially with regard to deterioration caused by the corrosion of steel reinforcement. One of the promising avenues to overcome this problem is to take advantage of the non corrosive characteristic of the Fiber Reinforced Polymer (FRP) bars in reinforcing and/or prestressing concrete bridges. In addition FRP bars have high specific strength, i.e., strength to weight ratio, when compared to conventional steel. Using FRP bars in a combined system of internal prestressing and external post-tensioning provides a potential solution to increase the service life of concrete bridges. However, …
Scour By Submerged Square Wall Jets At Low Densimetric Froude Numbers., Partha Sarathi
Scour By Submerged Square Wall Jets At Low Densimetric Froude Numbers., Partha Sarathi
Electronic Theses and Dissertations
In this research an effort is made to better understand the scour caused by submerged square jets in a cohesionless bed. The variables of interest are the densimetric Froude number, the tailwater depth and sediment grain size. Experiments were carried out at three different values of densimetric Froude numbers (= 3.9, 6.6 and 10.0), a range of tailwater conditions varying from low to very high submergence, and two different sand bed grain sizes. Velocity measurements were conducted using a laser Doppler anemometer. At a given densimetric Froude number, progressing from the start of the test towards asymptotic conditions, the geometric …
Modal Identification Using Optimization Approach., Li Li
Modal Identification Using Optimization Approach., Li Li
Electronic Theses and Dissertations
In this thesis, the modal identification problem is pursued using two different optimization approaches. The first approach is a deterministic optimization approach that minimizes the output model error in the time domain between a direct solution using the modal model and the measured response. Examples of single-input single-output identification are used to illustrate this method; it has been shown this approach is robust against noise and can be used to fine-tune the modal parameter, especially for the damping. The second approach is based on probabilistic optimization; the objective function is defined as the a posteriori probabilistic density of the parameters …
Characteristics Of Confined Square Jets In The Vicinity Of A Free Surface., Girish Sankar
Characteristics Of Confined Square Jets In The Vicinity Of A Free Surface., Girish Sankar
Electronic Theses and Dissertations
The results of an experimental investigation of a turbulent jet flow issuing from a square nozzle in the vicinity of a free surface are presented. Experiments were conducted using a two-dimensional laser Doppler anemometer and a particle image velocimeter. The focus of this study was the near region of the jet (X/B < 30). Here, B refers to the nozzle width and X is the distance from the nozzle exit. LDA measurements were conducted at eight stations downstream of the nozzle exit along the centerline of the jet. Four tailwater depths were used in this study. Additional measurements were also conducted to identify axis switching and to this end measurements were obtained at various transverse locations. PIV measurements were conducted in the near jet region (X/B < 3) corresponding to a tailwater depth of 2.5B. A good comprehension of the fluid dynamics of a square jet expanding in the vicinity of the free surface is achieved. Higher order moments were calculated to provide information on the coherent structures and study the role of velocity fluctuations. Two local peaks on either side of the jet centerline is observed. The difference in magnitudes of the peaks indicate differences in the prevailing entrainment characteristics on the top and bottom portions of the jet. Through the quadrant analysis, sweep and ejection type events were observed. To better understand these events, four kinds of eddies are classified for simplicity and their behavior is discussed.* (Abstract shortened by UMI.) *This dissertation is a compound document (contains both a paper copy and a CD as part of the dissertation). The CD requires the following system requirements: Microsoft Office.Dept. of Civil and Environmental Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis2005 .S26. Source: Masters Abstracts International, Volume: 44-03, page: 1441. Thesis (M.A.Sc.)--University of Windsor (Canada), 2005.
Parametric Analysis Of Bolted Flange Connections Of Circular Monopoles., Olumadunwa Olusanya
Parametric Analysis Of Bolted Flange Connections Of Circular Monopoles., Olumadunwa Olusanya
Electronic Theses and Dissertations
The present study involved the parametric analysis of bolted flange connections of eighteen different circular monopoles. The parameters considered were the number of bolts (8, 6, and 4) and thickness of flange plate [25.4 mm (1.0 in.), 19.05 mm (0.75 in.) and 12.7 mm (0.50 in.)]. These were analyzed under stiffened and unstiffened conditions. Four, two and four stiffeners, 12.7 mm (0.50 in.) thick, were used with 8-, 6- and 4-bolt arrangements. Each finite element model is made up of a small diameter (171.5 mm) circular pipe and a large diameter (327 mm) circular pipe both welded to circular flanges. …
Dynamic Analysis Of Guyed Antenna Towers For Seismic Loads., Hussam M. Meshmesha
Dynamic Analysis Of Guyed Antenna Towers For Seismic Loads., Hussam M. Meshmesha
Electronic Theses and Dissertations
The increasing demand for personal communication services (PCS), such as digital cell phones and pagers, as well as digital television (DTV), has created new challenges for creating and maintaining telecommunications towers. For such communication tools, antenna towers are the best choice because they are relatively economical and effective for remote transmission, especially in North America where land area is large. Wireless firms are further pressured to complete digital systems within the next five years and to provide "seamless" coverage. The Canadian Standard for Antennas, Towers and Antenna-Supporting Structures, CSA-S37-01, provides guidance for seismic analysis of lattice towers. However, simplified design …
Experimental And Numerical Investigations Of Chemical Grouting In Heterogeneous Porous Media., Tirupati Bolisetti
Experimental And Numerical Investigations Of Chemical Grouting In Heterogeneous Porous Media., Tirupati Bolisetti
Electronic Theses and Dissertations
The objective of the present study is to understand the processes influencing the colloidal silica grout injection into porous media through experimental and numerical investigations. Experimental studies include viscosity measurements, grout injection into columns and grouted sand testing. The grout viscosities are measured during gelation under shear. Colloidal silica grout injection experiments are performed on two different sizes of columns to understand the grouting processes as well as to generate data for numerical simulations. The larger diameter column experiments are performed by varying colloidal silica solution and the type of water. The smaller diameter column (slim tube) experiment was conducted …
Investigation Of Total Gaseous Mercury In The Atmosphere Of The Great Lakes And St. Lawrence River Basin., Hongyu You
Investigation Of Total Gaseous Mercury In The Atmosphere Of The Great Lakes And St. Lawrence River Basin., Hongyu You
Electronic Theses and Dissertations
Mercury (Hg) is a highly toxic pollutant, and it can undergo long-range transport in the atmosphere. Hg is a pollutant of concern because of its tendency to accumulate and concentrate in biota. In this study, a statistical analysis of total gaseous mercury (TGM) was carried out using seven years of measurements at three Canadian Atmospheric Mercury Measurement Network (CAMNet) sites in the Great Lakes basin and three years measurements at two CAMNet sites in the St. Lawrence River basin. The average TGM concentrations ranged from 1.59 +/- 0.24 to 1.84 +/- 0.39 ng m-3 at the five sites. Two of …
Application Of Damage Mechanics For Fatigue Life Assessment., Md. Mustaqur Rahman
Application Of Damage Mechanics For Fatigue Life Assessment., Md. Mustaqur Rahman
Electronic Theses and Dissertations
Traditional multiaxial fatigue assessment models are based on the definition of an equivalent uniaxial measurement of the stress and strain tensors in the critical region of the studied component. An equivalent uniaxial criterion is then used to assess the fatigue life. In this thesis, we study a new approach based on Continuum Damage Mechanics theory. The introduction of the Continuum Damage Mechanics (CDM) in late 1970s to model fatigue has opened a new arena of research for developing a suitable model for multiaxial fatigue. In CDM, constitutive equations are derived by using internal variables under the framework of the thermodynamics …
Two-Dimensional Scour Hole Problem: Role Of Fluid Structures, Alex Bey
Two-Dimensional Scour Hole Problem: Role Of Fluid Structures, Alex Bey
Electronic Theses and Dissertations
An experimental program was carried out to further understand the scour caused by a plane wall jet. To this end, a two-dimensional laser Doppler anemometer was used to characterize the velocity field at various stations in the scour hole region. Present observations indicate that different types of flow structures influence scour at different time periods. Following vigorous digging caused principally by jet shear forces and impingement at the start of the test, the flow was characterized by the presence of longitudinal axial vortices, turbulent bursts and movement of the jet impingement point during the later stages. Attempts have been made …
P-Delta Effect For Leg Members Of Latticed Communication Towers., Mitul Shah
P-Delta Effect For Leg Members Of Latticed Communication Towers., Mitul Shah
Electronic Theses and Dissertations
Guyed Latticed Communication Towers are highly complex structures which are very difficult to model and analyze. Because of their geometric non-linearity, P-D effects are significant. To evaluate this, a sample guyed tower with one set of guys was modeled and linear and non-linear analyses were carried out to show the effect of P-D. Because of P-D effect, the moments are magnified by 1.29. The results show clearly that P-D effect cannot be ignored. Three representative guyed towers of 76.8 m (252 ft), 212 m (697 ft) and 583 m (1914 ft) height with four, five and nine guy levels respectively …
'Green' Manufacturing: A Life Cycle Inventory Of The Automotive Paint Process And Protocols For Industry Application., Angelos Anastassopoulos
'Green' Manufacturing: A Life Cycle Inventory Of The Automotive Paint Process And Protocols For Industry Application., Angelos Anastassopoulos
Electronic Theses and Dissertations
In response to growing interest in 'green' vehicles, Life Cycle Analysis (LCA) and Life Cycle Inventory (LCI) concepts can quantify the automobile's environmental impacts. Potential benefits include Design-for-Environment (DfE) opportunities, increased manufacturing efficiencies, and future application to consumer-based eco-rating systems. Detailed and up-to-date LCI data for general application by LCI practitioners does not exist at this time for the majority of Manufacturing/Assembly processes in North America, including the automotive paint process. With an Original Equipment Manufacturer (OEM) industry partner's commitment to a publicly available LCI database (i.e., NREL LCI Database), however, a representative vehicle assembly facility was selected for completion …
Reliability Analysis Of Laterally Loaded Piles Embedded In Soft Clay Below Water Table., Sunghan Lee
Reliability Analysis Of Laterally Loaded Piles Embedded In Soft Clay Below Water Table., Sunghan Lee
Electronic Theses and Dissertations
This study will present the theoretical formulation and numerical investigation of laterally loaded piles embedded in soft clay below the water table with random design variables. For the given statistical data on design parameters, it will determine the assessment of statistical performance of laterally loaded piles. The pile behavior depends on: the soil-pile material parameters (EI, b, epsilon50, c, gamma), which are considered as the random variables; type of load (force, bending moment); magnitude of load (nonlinear behavior); type of constraints (free head or fixed head) and type of structural system (single isolated pile or pile group). For single piles, …
Use Of Acoustic Emission Signals Through Steel Reinforcement To Detect The Onset Of Corrosion, Weiben Chen
Use Of Acoustic Emission Signals Through Steel Reinforcement To Detect The Onset Of Corrosion, Weiben Chen
Electronic Theses and Dissertations
Corrosion processes produce elastic energy waves in the form of acoustic emission (AE). For corrosion in reinforced concrete structures, AE waves are emitted beginning with the depassivation of oxide layers of reinforcing steel, the initial stage of corrosion processes. This study examines the feasibility of using AE technique to detect corrosion through steel reinforcement, which has relatively lower attenuation than concrete. Comparison of coupling AE sensors on steel and on concrete was made. Accelerated corrosion regime and two-channel multifunctional AE equipment with piezoelectric sensors were employed for laboratory experiments. The detectable distance from corrosion source to sensor was estimated via …
Dynamic And Static Analyses Of Continuous Curved Composite Multiple-Box Girder Bridges., Magdy Said Samaan
Dynamic And Static Analyses Of Continuous Curved Composite Multiple-Box Girder Bridges., Magdy Said Samaan
Electronic Theses and Dissertations
Horizontally curved concrete deck on multiple steel box girder bridges is a structurally efficient, economic, and aesthetically pleasing method of supporting curved roadway systems. Modern highway constructions are often in need of bridges with horizontally curved alignments due to the tight geometry restrictions. Continuous curved composite box girder bridges allow for the use of longer spans, thus reducing costs of the substructure. Despite all inherent advantages of continuous curved composite box girder bridges, they do pose challenging problems for engineers in calculating the load distribution due to moving vehicles across the bridges. Curved bridges are subjected to high torsional as …
Inactivation Of Laccase And Enzymatic Removal Of Phenol From Water., Shovini Dasgupta
Inactivation Of Laccase And Enzymatic Removal Of Phenol From Water., Shovini Dasgupta
Electronic Theses and Dissertations
Laccase, as a developmental preparation from an industrial enzyme producer, catalyzes the oxidation of phenols. The reaction products are insoluble polymers and are readily removed from the solution. Experiments were conducted to evaluate the potential use of laccase in an alternative enzyme based treatment technology to remove parent phenol from buffered distilled water at room temperature. All tests were conducted in continuously stirred batch reactor. pH was optimized. At an optimum condition of pH, effects of substrate concentration, product formation, dissolved oxygen (DO) availability, hydrogen peroxide addition, and aeration on phenol removal were investigated. The turnover capacity of laccase (defined …
Predicting Spatial Distributions Of Sediments In Fluvial Environments Using Kriging And Flowline Based Distances., Jason S. Wintermute
Predicting Spatial Distributions Of Sediments In Fluvial Environments Using Kriging And Flowline Based Distances., Jason S. Wintermute
Electronic Theses and Dissertations
The process of predicting reasonable spatial distributions of surficial sediments in fluvial environments using interpolation techniques can be quite challenging. The process of sediment transport creates anisotropy in the spatial distributions that follow the direction of flow. Standard geostatistical software only allow for the incorporation of one anisotropy direction for the entire problem domain. This is problematic for fluvial environments because an average direction usually misrepresents the local changes in anisotropy throughout the river. A distance transformation technique based on flowlines was applied in an attempt to improve the way geostatistical algorithms deal with anisotropy. The standard geostatistical method of …
Removal Of Reactive Azo Dyes From Water By Zero-Valent Iron Reduction Followed By Peroxidase-Catalyzed Polymerization., Mousumi Mani Biswas
Removal Of Reactive Azo Dyes From Water By Zero-Valent Iron Reduction Followed By Peroxidase-Catalyzed Polymerization., Mousumi Mani Biswas
Electronic Theses and Dissertations
Removing reactive azo dyes from textile wastewater is a significant challenge due to their color, non-biodegradability and toxicity. Although various treatment methods are available, it was hypothesized that reduction by zero-valent Fe followed by enzymatic treatment could be an environmentally friendly and cost effective approach. Zero-valent Fe cleaves the azo bond, reducing the dyes to aromatic amines, which are then oxidized and polymerized by enzymatic treatment. Finally, these polymers are removed by coagulant (PEI) aided sedimentation and filtration. The effectiveness of zero-valent Fe and Arthromyces ramosus peroxidase (ARP) treatment in the proposed process were studied on two representative reactive azo …
Sensitivity Analysis Of Laterally Loaded Piles Embedded In Stiff Clay Above Water Table., Lebing Liu
Sensitivity Analysis Of Laterally Loaded Piles Embedded In Stiff Clay Above Water Table., Lebing Liu
Electronic Theses and Dissertations
This study presents the theoretical formulation and numerical investigation of sensitivity analysis of laterally loaded piles embedded in stiff clay located above the water table. Single piles with various lengths and boundary conditions subjected to static and cyclic loadings applied to the pile-head as lateral forces and bending moments are analyzed. The cyclicity is introduced explicitly to p-y curve. The p-y soil response is of quasi static type. The pile groups of 3 x 3 piles with various spacing (2D, 3D, 4D and 5D) are also analyzed in the study. For single piles, the pile structure is considered as one-dimensional …
Short-Term Performance Of A Newly Developed Connection For Use In Precast Double Tee Systems., William D. Tape
Short-Term Performance Of A Newly Developed Connection For Use In Precast Double Tee Systems., William D. Tape
Electronic Theses and Dissertations
The focus of this work was to investigate the effectiveness of using advanced composite materials to enhance double tee to double tee connections in regions of significant seismic and lateral load. This work stems partly from the unfortunate losses experienced during the 1994 Northridge California earthquake. Moreover, this work was also developed from discussions with a local precasting company, which is concerned about premature failure of the connection due to stress concentrations. The author contends that the current connection method, intermittent welded plates, does result in stress concentrations, which can effect the system's overall performance. The proposed connection was formed …
Advancement Of Waste Management Strategies In Developing Nations (Costa Rica)., Luis Alvarez
Advancement Of Waste Management Strategies In Developing Nations (Costa Rica)., Luis Alvarez
Electronic Theses and Dissertations
Planning a comprehensive waste management strategy in developing nations can be both difficult and markedly different from established waste practices in developed nations. Commonly accepted data sampling methods and approaches to waste management may have to be modified extensively to suit an area's unique characteristics. This thesis proposes a waste sampling protocol and a waste management strategy appropriate for developing nations. The proposed methods of study were tested with data from the cities of San Pablo and San Isidro in Costa Rica at the Las Joyas dumpsite. Volume based sampling was found to be a reasonable approach where truck weigh …
Effect Of Welding On The Width Of The Heat-Affected Zone Of Aluminum Alloys., Vincent Aleo
Effect Of Welding On The Width Of The Heat-Affected Zone Of Aluminum Alloys., Vincent Aleo
Electronic Theses and Dissertations
Present aluminum design standards and specifications in North America require that the zone affected by welding be taken to extend a distance of 25 mm each side from the centre of the weld and that the yield strength of the metal in the zone affected by the weld be taken as the welded yield strength. The objective of this investigation is to determine the effect of welding on the width of the heat-affected zone (HAZ) of aluminum alloys. This was required for the development of an equation to determine the width of the HAZ for different parameters. One hundred and …
Effects Of Submergence And Test Startup Conditions On Local Scour By Plane Turbulent Wall Jets., Niranjan P. Deshpande
Effects Of Submergence And Test Startup Conditions On Local Scour By Plane Turbulent Wall Jets., Niranjan P. Deshpande
Electronic Theses and Dissertations
Experiments were carried out to study the interaction of plane turbulent wall jets with cohesionless soils during scour. The jet of water having a constant mean velocity of 1.16 m/s and thickness of 25.4 mm at the nozzle exit was set to initially flow tangentially along the sand bed with a median grain size of 2.15 mm. Both scour profile measurements and velocity measurements were obtained for a range of submergences, defined by the ratio of the tailwater depth to the nozzle opening. The results confirm the presence of two distinct types of flow fields, one that occurs at lower …