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Methods To Improve The Remediation Of Polycyclic Aromatic Hydrocarbons (Pahs) In Aerobic And Anaerobic Environments, Brian Wartell

Dissertations

Oil spills occur regularly in terrestrial environments and crude oil can contain many compounds that are highly resistant to degradation. Among these compounds are high levels of polycyclic aromatic hydrocarbons (PAHs) which are not only toxic but can also be carcinogenic and/or mutagenic. The first chapter of this dissertation includes an extensive review chapter on the variables affecting the anaerobic degradation of hydrocarbons, with a particular focus on PAHs. Electron acceptors, electron donors, temperature, salinity, pH all play key roles in determining the possibility effective of effective degradation occurring. Thus, by addressing solutions, such as biostimulation, improving environmental variables for …

Experimental And Numerical Characterization Of Multiphase Subsurface Oil Release, Feng Gao

Dissertations

Subsurface oil release is commonly encountered in the natural environment and engineering applications and has received the substantial attention of researchers after the disastrous Deepwater Horizon Blowout oil spill in 2009. The main focus on the present research is to systematically study the hydrodynamics of underwater oil jet under a variety of conditions, including the effect of dispersant and different gas to oil ratios (GOR) by using experimental measurement as well as a Computational Fluid Dynamics (CFD) approach, from which the measured turbulent characteristics (e.g., velocity, turbulent kinetic energy, turbulence dissipation rate, etc.) of underwater oil jet are thoroughly examined …

Costs And Benefits Of Flood Mitigation In Louisiana, Arash Taghi Nezhad Bilandi

LSU Doctoral Dissertations

Assessing the costs and benefits of hazard mitigation efforts is an essential component of disaster management, planning, and resilience assessment. These calculations are particularly important in locations vulnerable to multiple hazards with high frequencies, such as coastal Louisiana. This study aims to provide an improved understanding of the costs and benefits of flood mitigation efforts in Louisiana funded by federal government grants between 2005 and 2015. Project data provided by the Governor’s Office of Homeland Security and Emergency Preparedness (GOHSEP) were summarized and missing values were imputed using robust statistical approaches. Elevation project cost was investigated for prediction by statistical …

Controls On Phosphorus Export From An Agricultural Watershed: Amsden Brook, Fort Fairfield, Maine Usa., Gregory J. Mcdonald

Electronic Theses and Dissertations

This study explores the sources and mechanisms of phosphorus (P) mobilization during base flow within the Amsden Brook watershed, Fort Fairfield, Maine, USA. Amsden Brook is an agriculturally dominated watershed drained by a spring-fed and perennial first- to second-order stream. We characterized the P concentrations within the watershed to investigate connections between soils, stream sediment, surface water, and groundwater. Waters were monitored monthly during the 2017 snow-free period for temperature, pH, dissolved oxygen, conductivity, soluble reactive P (SRP), total P, strong acid anions, strong base cations, dissolved organic carbon (DOC), Al, Fe, and Mn. Phosphorus speciation within soils and sediment …

Laboratory Evaluation Of Recycled Crushed Glass Cullet For Use As An Aggregate In Beach Nourishment And Marsh Creation Projects In Southeastern Louisiana, John C. Wildman

University of New Orleans Theses and Dissertations

To combat the rapid degradation of the Louisiana coast, the Louisiana Coastal Protection and Restoration Authority has planned strategic land building initiatives throughout the Louisiana Gulf coast, including beach nourishment and marsh creation projects. It is commonly agreed that the state lacks sufficient renewable sediment resources to maintain the planned CPRA land building program. However, Louisiana, the state that commonly ranks last in state recycling percentage, recycles an estimated 0.6% of the waste glass consumed in the state. Glass is predominantly silica sand. This thesis evaluates laboratory‑determined characteristics of recycled crushed glass cullet to assess its suitability as a renewable …

Elevated Temperature Progressive Damage And Failure Of Duplex Stainless Steel, Darren P. Luke

Civil Engineering ETDs

Ductile failure of metals has been the focus of research efforts within academia and industry for many years since it is tremendously important for understanding the failure of structures under extreme loading conditions. However, limited research has been dedicated to elevated temperature ductile failure, which is critical for evaluating catastrophic events such as industrial, structural or shipping vessel fires. A detailed investigation was conducted on the structural response of Duplex Stainless Steel at elevated temperatures. The temperature dependence of elastic modulus, yield strength, ultimate strength, and ductility was measured up to 1000°C and a continuum damage plasticity model was developed. …

Spatial Exploration Of Trace Metals In Near-Surface Water And Soil In The Bolivian Altiplano, Lizzie Wilson

Civil and Environmental Engineering Theses and Dissertations

We analyzed soil and groundwater samples from the Bolivian Altiplano for trace metal concentrations, correlations and partitioning trends. Total digestion, sequential extraction and loss on ignition experiments were performed on soil samples. We ran aqueous samples on an ICP-MS. Results were analyzed to identify trace metal concentrations and find any significant correlations. We generated interpolated maps in ArcGIS to spatially analyze results. Results for elevated concentrations of interest were divided into sub-groups of organophilic metals, oxoanions and divalent metals and include vanadium, arsenic, selenium, zinc, nickel, lead, cobalt, uranium, copper and manganese. These elements are likely naturally sourced. We found …

Performance-Based Economical Seismic Design Of Multistory Reinforced Concrete Frame Buildings And Reliability Assessment, Chunyu Zhang

UNLV Theses, Dissertations, Professional Papers, and Capstones

As the next generation of seismic design methodology, performance-based seismic design (PBSD) method requires a structure satisfy multiple preselected performance levels under different hazard levels. Optimal PBSD methods provide different strategies to design the numerous variables, including strength, stiffness and ductility of each structural component. The overall goal of this study is to develop a new optimal PBSD method for multi-story RC moment frames. This method is capable of overcoming the deficiencies of existing optimal PBSD methods and can be implemented by the U.S. design practice. The proposed method minimizes construction cost and takes the limit of member plastic rotation …

Mechanisms Of Calcium Phosphate Mineralization On Biological Interfaces And Their Engineering Applications, Doyoon Kim

McKelvey School of Engineering Theses & Dissertations

All living organisms utilize phosphorus (P) as an essential component of their cell membranes, DNA and RNA, and adenosine triphosphate. Bones, in addition to bearing loads, play an important role in balancing P levels in our bodies. In bones, a network of collagen templates and calcium phosphate (CaP) nanocrystals builds hierarchical levels, from nano- to macroscale. Within this architecture, the thermodynamic properties of CaP minerals are influential. Despite the importance of nucleation, growth, and crystallization in collagen structures for tissue development, little kinetic study of these processes has been conducted due to the limited in situ techniques for monitoring these …

Effect Of Curing Conditions On Mechanical Properties And Durability Of Concrete, Edgar Lazaro Salas-Borrero

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis presents the results for three different concrete mix designs with compression strengths of 4500 psi. The experiment was conducted in the Las Vegas area during the summer, from August 16th to October 12th, 2018, where temperatures and relative humidity was recorded daily, three times a day. In total, 135 concrete specimens (4” x 8”) were taken on site and were subjected to five different curing conditions.

For each concrete mix design, three concrete samples (4” x 8”) were taken and submitted for each curing condition, resulting in 45 cylinders for each concrete mix design. The same number of …

Surface Resistivity For Concrete Quality Assurance, Stanley Tat

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this study was to determine the effectiveness of SRT for concrete quality assurance and to evaluate the relationship between SRT and the three chloride ion ingress methods currently used by various State DOTs. Additionally, the influence of binder type and content, concrete age, and water-to cementitious materials ratio on the experimental results were also examined.

In this study, Type V Portland and three SCMs; namely fly ash, slag, and silica fume were used. Fine and coarse, aggregates were supplied by a local quarry. To evaluate the transport properties of the studied concretes, RMT, RCPT, and ACT were …

Calculation Of Access Charge For High Speed Rail Xpresswest Of Nevada, Sameeksha Sapkota

UNLV Theses, Dissertations, Professional Papers, and Capstones

XpressWest is a High Speed Rail (HSR) system that plans to connect Las Vegas with California at Palmdale. It will utilize the railway network of the California High Speed Rail (CAHSR) to connect Las Vegas with California destinations that include Los Angeles and San Francisco. For sharing the railway network of CAHSR, XpressWest will pay certain charge known as an access charge. The access charge is the fee paid by the train operator to the infrastructure owner for the addition of trains in a track. There are several access charge systems in the world. However, there is no study that …

A Comprehensive Study Of Arsenic Removal From Aqueous Solution Using Low-Cost Adsorbents, Mrinmoyee Mondal

Electronic Thesis and Dissertation Repository

Arsenic poisoning in water is a global concern for many years due to its high carcinogenic and toxic effect on the human body. Adsorption is one of the promising technology to treat arsenic-contaminant water. Recently, natural adsorbent modified with metal oxide/hydroxide is being studied widely, because of its great removal efficiency, inexpensive and eco-friendly properties.

In the present study, two low-cost adsorbents namely Aerocrete and Vermiculite (modified with iron oxy-hydroxide) were assessed for arsenic (both As(III) and As(V)) removal. The maximum removal of As(V) was ~99% at pH 6 for both adsorbents (3g/L). Optimum removal of As(III) was observed at …

An Engineered Fit-For-Purpose Polymer Nanocomposite Seal Repair Material For Wellbores, Moneeb Genedy

Civil Engineering ETDs

Seal integrity of wellbores has become of significant interest due to repeated leakage and spill incidents occurring worldwide that jeopardize both human health and the environment in addition to causing significant economic burden. This is attributed to the fact that wellbores intersecting geographical formations contain potential leakage pathways. The cement-steel and cement-rock formation interfaces are recognized as two critical leakage pathways.

A seal repair material that has good bond strength with both steel and rock formations in addition to the ability to completely fill thin microcracks is needed to restore the seal integrity of wellbores. In this research, engineered polymer …

Aversion And Warning Factors For Assessing Existing Reinforced Concrete Structures, Marcie Van Weerdhuizen

Electronic Thesis and Dissertation Repository

In a world of aging infrastructure, sustainability initiatives require additional investment in the assessment of existing reinforced concrete structures. Reliability-based assessment should minimize costs by reducing conservatism, while ensuring levels of safety equivalent to those for new designs. Current Canadian and US provisions assign target reliability levels for structural assessment based on criteria including occupancy type, expected failure behaviour, and the effect of element failure on the overall structural integrity. These criteria are defined using discrete and qualitative parameter values. It is shown that the true structural conditions can be better represented by verifying the applicability and completeness of these …

From Probabilistic Socio-Economic Vulnerability To An Integrated Framework For Flash Flood Prediction, Sepideh Khajehei

Dissertations and Theses

Flash flood is among the most hazardous natural disasters, and it can cause severe damages to the environment and human life. Flash floods are mainly caused by intense rainfall and due to their rapid onset (within six hours of rainfall), very limited opportunity can be left for effective response. Understanding the socio-economic characteristics involving natural hazards potential, vulnerability, and resilience is necessary to address the damages to economy and casualties from extreme natural hazards. The vulnerability to flash floods is dependent on both biophysical and socio-economic factors. This study provides a comprehensive assessment of socio-economic vulnerability to flash flood alongside …

Treated Versus Untreated Aggregate Bases For Flexible Pavements: A Nationwide Comparitive Study, Hemant Gc, Mena I. Souliman

Civil Engineering Theses

Aggregates are a major part of highway construction and its quality as well as strength affects the overall performance of the pavement structure. The base material near the construction site does not always meet the strength requirement needed for the pavement construction and the hauling of quality aggregate increases the construction costs. For better use of local available materials, stabilizing agents such as lime and asphalt cement have been utilized to increase the strength of crushed aggregate bases. Performance of pavement structures is heavily influenced by the thickness of the structure as well as material properties of each layer. The …

Experimental Testing And Modeling Of Partial Nitrification At Different Temperatures, Xiaoguang Liu

Electronic Thesis and Dissertation Repository

Nitrogen in wastewater treatment plant effluents has adverse environmental effects on aquatic systems. Excessive concentrations of nitrogen in water bodies can result in the depletion of dissolved oxygen, deterioration of water quality, and shifts of biotic community. Conventional biological nitrogen removal (BNR) processes consume high energy for nitrification and require external carbon for denitrification. Alternatively, partial nitrification is of interest as an emerging technology for its lower need of organic carbon addition and cost savings in aeration. In this study, the main objectives are: 1- developing a mathematical model involving operational parameters for the determination of successful partial nitrification conditions; …

Attributing Accelerated Increases In Salinity In The Mediterranean Coastal Zone To Climate Change And Seawater Desalination Brine And The Resultant Unsustainability Of Modern Desalination Technology, Brandon W. Harper

HCNSO Student Capstones

Anthropogenic climate change influences our oceans on a global scale and has brought about increased salinity levels in large areas of our oceans such as the North Atlantic (Dunbar 2009). Concentrations of large scale desalination plants around small bodies of water add to this pattern and have shown even larger increases in salinity due to desalination brine discharge (Purnama et al., 2005). Salinity profile data over time should show similar increases in salinity in the Mediterranean Sea due to climate change and localized data should show increased salinity due to brine discharge. This study aims to pinpoint the extent of …

A Microscopic Simulation Laboratory For Evaluation Of Off-Street Parking Systems, Yun Yuan

Theses and Dissertations

The parking industry produces an enormous amount of data every day that, properly analyzed, will change the way the industry operates. The collected data form patterns that, in most cases, would allow parking operators and property owners to better understand how to maximize revenue and decrease operating expenses and support the decisions such as how to set specific parking policies (e.g. electrical charging only parking space) to achieve the sustainable and eco-friendly parking.

However, there lacks an intelligent tool to assess the layout design and operational performance of parking lots to reduce the externalities and increase the revenue. To address …

The Live Load Response Of The Open Web Steel Joist Black Slough Bridge, Piero Caputo

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

The bridge being studied spans the Black Slough River in the Nucor/Vulcraft facilities near Brigham City, Utah. The bridge is composed of seven heavyweight open web steel joists supporting a concrete deck-slab element and sitting in two concrete cantilever walls serving as bearings. A full-scale live-load test was performed using forklift vehicles at four locations on the deck. During the test, axial strains, deflections, and rotations where measured.

In their provisions, the American Association of State Highway and Transportation Officials (AASHTO) included a simplified number of equations and solutions used to calculate GDFs for standardized decks supported by beam systems. …

Controlling Relative Humidity Using Glycerin, Juan Martinez

Civil Engineering Undergraduate Honors Theses

A series of tests were conducted to control relative humidity (RH) using a bubbler system that contained a series of glass jars and glass vials filled with different concentrations of glycerin. The relative humidity within the glass jars was measured. The total time interval for each laboratory test was 48 hours. During the first 24 hours a pump was used to bubble air through the glycerin solution. During the second 24 hours, the pump was turned off, and the RH within the system was monitored within the closed system. Target RH measurements from 100% to a 0% were obtained. The …

Midpoint And Endpoint Sustainability Assessment Of U.S. And China Manufacturing: A Comparative Mrio+Recipe Analysis, Mustafa Saber

Master's Theses

Manufacturing is among the most important industries for an economy, which creates value-added, fosters innovation, stimulates employment and economic growth. Therefore, manufacturing industries are crucial for a country’s sustainable development not only for economic reasons but also for social (.e.g. employment, tax, etc.) and environmental ones. Thus, manufacturing activities’ contribution to the economy is critically related with environmental and social impacts. Sustainable economic growth is essential and necessary for a country to provide all necessary goods and services to its growing population.

And, this is highly linke with the creation of new jobs and in this context, manufacturing jobs have …

Young’S Modulus As A Measurement To Estimate Damage Related With Alkali-Silica Reaction In Concrete., Anazaria J. Ortega Gonzalez

Civil Engineering Undergraduate Honors Theses

The main purpose of this research is to compare two nondestructive methods to assess Alkali-Silica reaction (ASR) in concrete. Fifteen concrete prisms were cast using aggregates with different Alkali-Silica reactivity such as Jobe sand and Van Buren sand. The change in strain, shear wave velocity and Young’s modulus were determined according to ASTM C129 and ASTM C215, respectively. This data was collected by Dillon K Self, who determined that the shear wave velocity and strain are inversely proportional. However, when single cracking in the concrete specimen transition to map cracking, the shear wave velocity dropped significantly, whereas the strain value …

Evaluation And Influence Of Recycled Concrete Aggregate Base Layers On Hma Pavement Performance, Jessie Daniel Ramirez

Theses and Dissertations

This research investigated the influence of the RCA base layers on the HMA pavement performance as compared with CA base layers using laboratory tests on collected base layer materials and field tests on corresponding pavement sections. Field and laboratory testing programs were conducted to investigate RCA and CA base layer materials in which identified test sections at the selected pavement sites were subjected to testing using FWD, walking profiler, and DCP. Visual distress surveys were also conducted at the selected pavement sections. RCA and CA base layer samples were collected from these pavement sites and were subjected to a laboratory …

Swat Online: Development Of A Web-Based Decision Support System For The Soil And Water Assessment Tool, Spencer Dean Mcdonald

Theses and Dissertations

As satellite and climate modelling technology continues to improve and as climatological disasters and issues continue to impact the global community, climate data will increase in size and relevance. With this new influx of information, it is becoming more and more important for scientists to simply and concisely communicate their findings to both decision makers in governments and disaster preparedness organizations and also to the general public. The Soil and Water Assessment Tool (SWAT) is a powerful modelling tool that allows scientists to simulate essentially all of the physical processes involved in the water cycle. The data that SWAT produces …

Relationship Between Compressive Strength Of Different Shape And Thickness Specimens Of Type S Mortar, Theodore James Moffett

Theses and Dissertations

Mortar is the cementitious binding material placed between masonry blocks to create a composite system. The American Society of Testing and Materials (ASTM), along with other organizations, have established the testing of prismatic mortar specimens for evaluating mechanical properties, like compressive strength. Mortar joints, however, possess vastly different characteristics compared to prismatic specimens, especially in terms of geometry and water content. These differences prevent a direct comparison of compressive strength between prismatic specimens and actual mortar joints in the assembly. The objective of this study was to analyze Type S mortar joints, with particular emphasis on specimen shape and water …

Experimental Evaluation Of Replaceable Shear Fuse Moment Connections, Shannon Shun Oh

Theses and Dissertations

Steel special moment frames (SMFs) are known to be highly ductile seismic force- resisting systems. The performance of an SMF relies on the ability of the connections to accommodate large inelastic deformations. After the brittle failure of some steel moment frame connections during the 1994 Northridge Earthquake, experimental tests were used to investigate the ductility and strength of these connections. An experimental study was performed to investigate the seismic performance a new connection called the Replaceable Shear Fuse (RSF) connection. The RSF connection uses shear-yielding fuse plates to prevent beam and column yielding. A total of 7 test specimens with …

Development Of A Simplified Analysis Approach For Predicting Pile Deflections Of Piers Subjected To Lateral Spread Displacements And Application To A Pier Damaged During The 2010 Maule, Chile, M8.8 Earthquake, Logan Matthew Palmer

Theses and Dissertations

The 2010, moment magnitude 8.8 earthquake that occurred near Maule, Chile caused major damages to several piers in the Port of Coronel located approximately 160 kilometers (100 miles) to the South of the earthquake epicenter. One of the piers, the North Pier, experienced significant lateral spreading that was caused from liquefaction of the soils at the approach zone of the pier. Damages from lateral spreading and liquefaction effects consisted of sheet pile welding ruptures of the cross-support beams, stiffener buckling, pile displacements, pile rotations, and pier deck displacement. Researchers analyzed the North Pier after the earthquake and documented in detail …

A Flexible Service-Oriented Approach To Address Hydroinformatic Challenges In Large-Scale Hydrologic Predictions, Michael Antonio Souffront Alcantara

Theses and Dissertations

Water security is defined as a combination of water for achieving our goals as a society, and an acceptable level of water-related risks. Hydrologic modeling can be used to predict streamflow and aid in the decision-making process with the goal of attaining water security. Developed countries usually have their own hydrologic models; however, developing countries often lack hydrologic models due to factors such as the maintenance, computational costs, and technical capacity needed to run models. A global streamflow prediction system (GSPS) would help decrease vulnerabilities in developing countries and fill gaps in areas where no local models exist by providing …