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The Effects Of Silica On The Properties Of Vitreous Enamels, Signo Tadeu Dos Reis, Mike Koenigstein, Liang Fan, Genda Chen, Luka Pavic, Andrea Mogus-Milankovic

Materials Science and Engineering Faculty Research & Creative Works

Ground coat enamels for low carbon steel that contain silica as a mill addition have been developed to study the changes of their properties. Acid-resistant commercial enamel where silica addition was varied from 0 to 10.0 wt % was used for this investigation. The effects of the addition on the corrosion resistance, thermal properties, electrical properties, and mechanical adherence of the enamel to low carbon steel were studied. The corrosion resistance of the steel enameled coupons was tested using a salt spray (fog) apparatus for time periods reaching 168 h at room temperature. It was found that, although the density …

Experimental Study Of Low Cycle Fatigue Properties For Epoxy Resins With Dibutyl Phthalate (Dbp), Zhi Wang, Jiajia Zhou, Lianjian Song, Long Li

Department of Civil, Environmental, and Geospatial Engineering Publications

In order to improve the toughness of traditional epoxy resin, dibutyl phthalate (DBP) was introduced into the epoxy resin. The static mechanical performance of plasticized and unplasticized epoxy resin was evaluated. The test results showed that the DBP modified epoxy resin can obtain a higher toughness than conventional epoxy resin, but the elastic modulus and the tensile strength were slightly reduced. The low cycle fatigue test results indicated that the stress ratio and the stress level were two critical factors of fatigue life, which was increased with the growth of stress ratio. It was also found that the fatigue life …

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 …

Laboratory Study On The Strength Behaviour Of Two Laterally Loaded Adobe Walls, Brad D. Weldon, Paola Bandini, Michael J. Mcginnis, Eduardo Dávila, Diego I. Garcia Vera

Civil Engineering Faculty Publications and Presentations

Adobe is a traditional construction technique found in historic and new construction throughout the world, often in earthquake-prone regions. Adobe structures are particularly susceptible to seismic forces due to their substantial mass and low tensile capacity. In addition, adobe is affected negatively by moisture that may penetrate from the ground or through the plaster. This paper describes the preliminary findings of an experimental program to investigate the effect of higher water content in the lower part of the wall on the wall strength behaviour under lateral loading. Lateral load tests were conducted on two quarter-scale adobe walls, one in air-dry …

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 …

Dynamic Response Analysis Of Rutting Resistance Performance Of High Modulus Asphalt Concrete Pavement, Chundi Si, Enli Chen, Zhanping You, Riulan Tian, Ran Zhang, Junfeng Gao

Department of Civil, Environmental, and Geospatial Engineering Publications

In order to systematically study the rutting resistance performance of High-Modulus Asphalt Concrete (HMAC) pavements, a finite element method model of HMAC pavement was established using ABAQUS software. Based on the viscoelasticity theory of asphalt, the stress and deformation distribution characteristics of HMAC pavement were studied and compared to conventional asphalt pavement under moving loads. Then, the pavement temperature field model was established to study the temperature variation and the thermal stress in HMAC pavement. Finally, under the condition of continuous temperature variation, the creep behavior and permanent deformation of HMAC pavement were investigated. The results showed that under the …

Preface: Earth Observation For Integrated Water And Basin Management: Challenges For Adaptation To A Changing Environment, María J. Polo, Maria P. González-Dugo, Christopher M.U. Neale

Daugherty Water for Food Global Institute: Faculty Publications

Integrated river basin management involves a sound knowledge of water and land interactions, and impacts from and feedbacks to human activity. Remote sensing has been an efficient and increasingly promising means of gathering direct information of the Earth surface, as well as information on water and energy fluxes. The recent generation of high-resolution sensors offers a huge potential for monitoring, assessing, and modelling our changing environment in a context of uncertainty about how future climate conditions will affect the current water resource and basin management framework. Moreover, large amounts of data are now available posing a challenging opportunity to the …

Spatial And Temporal Analysis Of Precipitation And Effective Rainfall Using Gauge Observations, Satellite, And Gridded Climate Data For Agricultural Water Management In The Upper Colorado River Basin, Mahyar Aboutalebi, Alfonso F. Torres-Rua, L. Niel Allen

Civil and Environmental Engineering Faculty Publications

Accurate spatial and temporal precipitation estimates are important for hydrological studies of irrigation depletion, net irrigation requirement, natural recharge, and hydrological water balances in defined areas. This analysis supports the verification of water savings (reduced depletion)from deficit irrigation of pastures in the Upper Colorado River Basin. The study area has diverse topography with scattered fields and few precipitation gauges that are not representative of the basin.Gridded precipitation products from TRMM-3B42, PRISM, Daymet, and gauge observations were evaluated on two case studies located in Colorado and Wyoming during the 2014–2016 irrigation seasons. First, the resolution at the farm level is discussed. …

Evaluating Future Flood Scenarios Using Cmip5 Climate Projections, Narayan Nyaupane, Balbhadra Thakur, Ajay Kalra, Sajjad Ahmad

Civil and Environmental Engineering and Construction Faculty Research

Frequent flooding events in recent years have been linked with the changing climate. Comprehending flooding events and their risks is the first step in flood defense and can help to mitigate flood risk. Floodplain mapping is the first step towards flood risk analysis and management. Additionally, understanding the changing pattern of flooding events would help us to develop flood mitigation strategies for the future. This study analyzes the change in streamflow under different future carbon emission scenarios and evaluates the spatial extent of floodplain for future streamflow. The study will help facility managers, design engineers, and stakeholders to mitigate future …

Lifecycle Modeling And Assessment Of Unmanned Aerial Vehicles (Drones) Co2e Emissions, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

There are no studies that model the potential effectiveness of Unmanned Aerial Vehicles (UAVs) or drones to reduce CO2e lifecycle (including both utilization and vehicle phase) emissions when compared to conventional diesel vans, electric trucks, electric vans, and tricycles. This study presents a novel analysis of lifecycle UAV and ground commercial vehicles CO2e emissions. Different route and customer configurations are modeled analytically. Utilizing real-word data, tradeoffs and comparative advantages of UAVs are discussed. Breakeven points for operational emissions are obtained and the results clearly indicate that UAVs are more CO2e efficient, for small payloads, than conventional diesel vans in a …

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. …

Riverbank Filtration Impacts On Post Disinfection Water Quality In Small Systems—A Case Study From Auburn And Nebraska City, Nebraska, Matteo D'Alessio, Bruce Dvorak, Chittaranjan Ray

Daugherty Water for Food Global Institute: Faculty Publications

Small water systems can experience a fluctuating quality of water in the distribution system after disinfection. As chlorine is the most common disinfectant for small systems, the occurrence of disinfection byproducts (DBPs) represents a common problem for these systems. Riverbank filtration (RBF) can be a valuable solution for small communities located on riverbanks. The objectives of this study were to evaluate (i) the improvements in water quality at two selected RBF systems, and (ii) the potential lower concentrations of DBPs, in particular, trihalomethanes (THMs), in small systems that use RBF. Two small communities in Nebraska, Auburn and Nebraska City, using …

Optimal Placement Of Distributed Energy Storage Systems In Distribution Networks Using Artificial Bee Colony Algorithm, Choton K. Das, Octavian Bass, Ganesh Kothapalli, Thair S. Mahmoud, Daryoush Habibi

Research outputs 2014 to 2021

The deployment of utility-scale energy storage systems (ESSs) can be a significant avenue for improving the performance of distribution networks. An optimally placed ESS can reduce power losses and line loading, mitigate peak network demand, improve voltage profile, and in some cases contribute to the network fault level diagnosis. This paper proposes a strategy for optimal placement of distributed ESSs in distribution networks to minimize voltage deviation, line loading, and power losses. The optimal placement of distributed ESSs is investigated in a medium voltage IEEE-33 bus distribution system, which is influenced by a high penetration of renewable (solar and wind) …

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 …

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 …

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 …

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 …

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 …

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 …

Comparing Beijing's And Tokyo's Population Growths, Ernest M. Oleksy

The Downtown Review

The growth of the human population has led to the formation of largely populated agglomerations known as megacities. Although megacities can be found on multiple continents, Asia’s collection displays how megacities can develop in their own directions. Japan’s megacity of Tokyo, like other Japanese megacities, has adopted a western approach. China’s Beijing, on the other hand, continues to embrace its eastern roots. These megacities may differ in their ideologies, but they share in experiencing similar phenomena. One of these phenomena is population growth.

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 …

Walker, Dorian (Fa 1240), Manuscripts & Folklife Archives

FA Finding Aids

Finding aid only for Folklife Archives Project 1240. Collection of oral history interviews with railroad employees, locals, and historians recorded on Betacam and Betacam SP for Dorian Walker’s 1995 film Beauty of the Southland. Portions of the interviews were also used for a 2010 miniseries, All Aboard.

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 …

Flow Analysis Through Collectorwell Laterals: A Case Study From Sonoma County Water Agency, California, Matteo D'Alessio, John Lucio, Ernest Williams, Donald Seymour, Jay Jasperse, Chittaranjan Ray

Daugherty Water for Food Global Institute: Faculty Publications

The Sonoma County Water Agency (SWCA) uses six radial collector wells along the Russian River west of Santa Rosa, to provide water for several municipalities and water districts in north-western California. Three collector wells (1, 2, and 6) are located in the Wohler area, and three collector wells (3, 4, and 5) are located in the Mirabel area. The objective of this paper is to highlight the performance of the three collector wells located in the Mirabel area since their construction. The 2015 investigation showed a lower performance of Collectors 3 and 4 compared to their original performances after construction …

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 …

Assessing The Feasibility Of Soil Infiltration Trenches For Highway Runoff Control On The Island Of Oahu, Hawaii, Martina Sobotkova, Jaromir Dusek, Ghasem Alavi, Laxman Sharma, Chittaranjan Ray

Daugherty Water for Food Global Institute: Faculty Publications

The coastal waters of Hawaii are extremely important for recreation as well as for the health of the marine environment. Non-point source pollution from storm runoff poses a great threat to surface water quality in Hawaii. The State of Hawaii Department of Transportation (HDOT) includes infiltration trenches as a best management practice (BMP) option to reduce pollution caused by stormwater runoff. HDOT guidelines state that the implementation of BMPs is needed to reduce sediment and pollutant loads to streams and the ocean. In this study, the suitability of soils adjacent to highways on Oahu for the siting of infiltration trenches …