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Performance Evaluation Of A Coupled Photovoltaic-Thermal Solar Powered Desalination Pilot System, Martin Chavarin

Open Access Theses & Dissertations

A pilot scale coupled photovoltaic-thermal solar powered desalination system was evaluated at the Brackish Groundwater National Desalination Research Facility (BGNDRF). The pilot system consisted of a 3-kW photovoltaic-thermal (PVT) solar panel array and a 2.3 kW photovoltaic (PV) array coupled with a 4 gal/min single-stage 4 membrane reverse osmosis (RO) desalination system. A heat exchange system was in place to provide simultaneous cooling for the PVT system and heating to the RO system feed water. This system was evaluated with three objectives in mind. The first objective was to identify whether cooling of the PVT panels resulted in a significant …

How Active Rainwater Harvesting May Help Reduce Nuisance Flooding: Flood Analysis And Social Barriers To Adoption, Isabel Lopez

Open Access Theses & Dissertations

As urbanization continues to expand, fewer pervious surfaces are available to help reduce stormwater runoff from rainfall. The impacts of urbanization are becoming evident through sunny day flooding - flooding that occurs in areas not designated by the Federal Emergency Management Agency (FEMA) as flood zones. Nevertheless, water accumulates in low-lying areas and compromises street intersections and other parts of neighborhoods. Some methods can help alleviate the impacts of unexpected heavy rains, such as passive and active rainwater harvesting. As a pilot study, in a selected area in the northeast of El Paso, the level of adoption (e.g., what percentage …

High-Energy Storm Events And Their Impacts On Carbon Storage In Tidal Wetlands Of South Carolina, Gavin Gleasman

All Dissertations

Atmospheric carbon dioxide (CO₂) concentrations have been increasing at an accelerating rate for the past two centuries, profoundly impacting global climate change. Atmospheric CO₂ concentrations are influenced by the global carbon cycle through physical and biogeochemical pathways. Tidal wetland environments play a vital role in the global carbon cycle by offsetting atmospheric CO₂ concentrations through their natural physiochemical processes of high autotrophic productivity, allochthonous organic matter deposition, anoxic soils, and continuous accretion which promotes carbon sequestration with long-term storage at the land-ocean margin. The Intergovernmental Panel on Climate Change (IPCC) and United States Global Change Research …

Developing An Early Warning System Of Highway Slope Failure Based On In-Situ Hydraulic Conductivity Of Soil, Alinda Gupta

Civil Engineering Dissertations - Archive

Highway slope failure is globally a momentous issue. Highway slope failure poses a significant issue in transportation infrastructure. Several factors can contribute to slope failures, including geological conditions, weather events, and human activities. Weather events like heavy rainfall, cyclic shrinkage and swelling can trigger slope failures constructed on high plastic clays. It increases pore water pressure, causing soil saturation, and inducing failure. The consequences of highway slope failures are severe, ranging from traffic disruptions, road closures, and damage to vehicles and infrastructure, to potential injuries or loss of lives. Addressing and mitigating slope failure risks is crucial for ensuring the …

An Accelerated Corrosion Test Method For Pre-Cracked Reinforced Concrete, Shahriar Abed

Civil Engineering Dissertations - Archive

Reinforced concrete (RC), a composite material combining the strength of concrete and the tensile strength of steel reinforcement, has significantly transformed the field of civil engineering and contributed to the advancement of modern infrastructure. Reinforced concrete structures are susceptible to deterioration over time despite their numerous advantages. One of the primary factors leading to the degradation of RC is the corrosion of steel reinforcement, primarily caused by exposure to aggressive environmental elements such as chloride ions, carbonation, and moisture. This dissertation aims to provide valuable insights into the accelerated corrosion behavior of steel bars embedded in concrete, considering factors such …

Phase Distribution Of Nickel, Chromium, And Cobalt In Seawater At Olivine-Enriched Beaches: Implications For Carbon Capture By Enhanced Silicate Weathering, Nathaniel J. Padrnos

Master's Theses

The application of olivine to coastal areas is a proposed method of removing carbon dioxide from the atmosphere for climate change mitigation. Olivine is abundant and dissolves relatively fast, but it contains trace amounts of nickel (Ni), chromium (Cr), and cobalt (Co) which may be toxic to marine biota in cases of widespread coastal olivine spreading. Prior studies have suggested that Ni concentrations in marine sediments and/or the overlying water column due to olivine dissolution could be a limiting factor for its carbon capture potential. Therefore, it is critical to understand and model the processes affecting trace metal bioavailability after …

Multiphysics Numerical Modeling For Pfas Transport Within Vadose And Saturated Zones, Pierrette Iradukunda

Boise State University Theses and Dissertations

The extent and severity of wildfires have increased around the world, necessitating a greater understanding of the consequences of wildfire and post-fire impacts on soil and groundwater. Wildfire suppression techniques like aqueous film-forming foams (AFFF) can also contaminate the soil with per- and polyfluoroalkyl substances (PFAS), which can contribute to human and environmental health concerns. PFAS are dangerous man-made chemical compounds that are persistent, mobile, poisonous, and a major cause of soil and groundwater contamination. In addition to contamination by aqueous film-forming foams, PFAS has accumulated in the environment as a result of being utilized in numerous other goods over …

Hydraulic Habitat Suitability For The Rio Grande Silvery Minnow At The Los Chavez Irrigation Outfall, New Mexico, Haley A. Ormsbee

Civil Engineering ETDs

It is essential to manage the Middle Rio Grande for aquatic species to preserve the native biodiversity of the river. During periods of low flow, endangered species such as the Rio Grande Silvery Minnow (RGSM) may get trapped in a drying reach without the ability to escape from isolated pools. Very little is known about how areas of refuge, such as irrigational outfall channels, buffer RGSM from stream flow intermittency. Hence, there is a crucial need to quantify available habitat for RGSM in areas of refuge. This study aims to make connections between flow regimes and physical-habitat conditions to help …

Evaluating Direct Filtration As An Alternative To Conventional Carbon-Based Advanced Treatment For Indirect Potable Reuse, Savannah M. Flemmer

Civil & Environmental Engineering Theses & Dissertations

Hampton Roads Sanitation District (HRSD) is recharging purified wastewater into the Potomac Aquifer via the Sustainable Water Initiative for Tomorrow (SWIFT) project. Conventional SWIFT treatment applies coagulation, flocculation, sedimentation, ozonation, biofiltration, granular activated carbon (GAC) adsorption, and ultraviolet disinfection to secondary effluent to produce water that meets drinking water standards for managed aquifer recharge. HRSD is considering implementing direct filtration as an alternative to conventional treatment for two additional SWIFT facilities. Direct filtration presents an opportunity for significant cost savings by eliminating sedimentation, shortening flocculation detention time, and reducing coagulant usage. Without upstream removal of solids and organics, however, biofilters …

Prairie Protector: Student Development Of Systems Thinking Habits In The Context Of Agroecosystems, Erin Ingram, Jennifer Keshwani

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Introduction: The Great Plains ecosystem offers an opportunity for young people to gain knowledge about intricate systems through practical learning. The spread of woody plants into grasslands, known as the “Green Glacier,” poses a risk to biodiversity and animal production. Although effective management strategies exist, some land managers are reluctant to use them. It is critical to cultivate a scientifically literate population that can think systematically and make informed decisions based on STEM principles to address such complex agroecosystem problems.

Methods: In this study, semi-structured focus group discussions with high school students were analyzed to determine whether Prairie …

Systematic Investigation Of Wavy Surface Roughness Profiles Using Common Roughness Algorithms, Russell Gray

Boise State University Theses and Dissertations

Roughness is an important parameter in rock engineering. Sine wave-based simulated wavy profiles were used to investigate systematic changes of amplitude and frequency on roughness indices. Profiles were 1000 mm in length with amplitude ranging from 0-10 mm and frequency ranging from 0-10 Hz. The roughness algorithms used were Root Mean Square (RMS), Energy, Sinuosity, Z2, Mean Absolute Angle (MAA), and Modified Divider a-Value. Roughness indices were visualized as contour plots. Similarities of the shapes and spacing of the contours as well as the magnitude of the roughness indices prompted the pairing of RMS and Energy algorithms, Z2 and MAA …

A Hybrid Lateral Flow Sand Filter Wastewater Treatment System: An Evaluation On The Treatment And Disposal Capabilities Of A Modified Sand Filter, Harry Mccaskill Iv

Graduate Theses and Dissertations (2019 - present)

Decentralized wastewater treatment exists primarily in suburban and rural areas where centralized treatment is not an option. Traditional on-site treatment systems usually include the use of a septic tank and a drain field. This orthodox method works well when implemented into environments that are accommodating for the infiltration of effluents, and thus allowing for soil treatment. Unfortunately, there are some circumstances that prevent traditional systems from working such as impermeable soil conditions. The Wastewater Treatment System analyzed in this thesis was created to overcome such inhospitable environments. More specifically, this system is catered towards the rural residences of The Alabama …

Rigid Pavement Analysis System (Rpas): An Enhanced Graphical User Interface, Samina Samrose

Open Access Theses & Dissertations

In recent decades there has been a significant interest among researchers in developing pavement analysis tools that will work with high efficiency and provide accurate results within a short timeframe. The University of Texas at El Paso (UTEP) has developed a finite element-based pavement analysis software named â??Rigid Pavement Analysis Systemâ?? (RPAS) capable of analyzing Jointed PCC pavements of any number of PCC and soil layers. The processing core of this software was developed in MATLAB with a pre- and post-processing user interface developed in C++. The MATLAB code is compiled into an executable and together with the C++ interface …

Improved Vehicle-Bridge Interaction Modeling And Automation Of Bridge System Identification Techniques, Omar Abuodeh

All Dissertations

The Federal Highway Administration (FHWA) recognizes the necessity for cost-effective and practical system identification (SI) techniques within structural health monitoring (SHM) frameworks for asset management applications. Indirect health monitoring (IHM), a promising SHM approach, utilizes accelerometer-equipped vehicles to measure bridge modal properties (e.g., natural frequencies, damping ratios, mode shapes) through bridge vibration data to assess the bridge's condition. However, engineers and researchers often encounter noise from road roughness, environmental factors, and vehicular components in collected vehicle signals. This noise contaminates the vehicle signal with spurious modes corresponding to stochastic frequencies, impacting damage monitoring assessments. Thus, an efficient and reliable SI …

Biocrude Production From Lignin In Hydrothermal Medium: Effect Of Rapid Heating And Short Residence Time, Kyoko Hirayama

Civil & Environmental Engineering Theses & Dissertations

This study aims to address knowledge gaps in the production of valuable products from waste streams generated during lignocellulosic biofuel production. The primary objective is to develop a process that converts lignin, a byproduct of bioethanol refineries, into a sustainable biolubricant.

The first chapter examines recent advancements in synthesizing biolubricants and investigates their scalability. It explores innovative materials, catalysts, chemical modification approaches, and additives that have emerged in the field. A particular hurdle is the oxidative stability of biolubricants derived from plant oils, which are prone to autooxidation due to their C=C bonds. To overcome this, the study aims to …

Adaptation Of Nirtrifiers And Heterotrophs To Low Dissolved Oxygen In An Activated Sludge Biological Nutrient Removal Pilot Plant, Shashank Khatiwada

Civil & Environmental Engineering Theses & Dissertations

Low dissolved oxygen (DO) operation is one of the innovative technologies in biological nutrient removal (BNR) processes that is being investigated due to the potential to reduce aeration requirements, reduce a treatment plant’s carbon footprint, and to lower costs associated with chemical addition to promote denitrification. These benefits are achieved through development of micro-zones, within aerated basins where simultaneous nitrification and denitrification (SND) can occur. In this study, an activated sludge BNR pilot was run in an anerobic/aerobic (A/O) configuration at a controlled temperature and constant flow to observe microorganism-driven transformations of nitrogen and phosphorus at varying low DO conditions. …

The Extent Of Drone Education Being Taught In Asc Schools To 4-Year Construction Students, Cheran Teja Dumpati

All Theses

The technology of Unmanned Aircraft Systems (UAS) is growing rapidly in many fields and has become one of the skills in demand in the industry. Universities are one of the primary sources of teaching drone technology with a career-oriented approach. The goal of this study is to investigate the content of the drone curriculum being taught in Associated Schools of Construction (ASC) schools. This includes the topics covered, practical training offered, and the key deliverables taught. This information serves as a foundation for the schools that are looking forward to start drone courses in their department. The research found that …

Drinking Water Quality Management Progress In Ontario, Two Decades After Walkerton, Megan Fuller, Emma Wells, Laith Furatian, Ian Douglas, Kaycie Lane

Department of Civil and Environmental Engineering: Faculty Publications

Following the waterborne disease outbreak in Walkerton, Ontario, the province made significant efforts to implement recommendations of the public inquiry that resulted. As Ontario reformed its drinking water sector, other jurisdictions were advancing risk-based quality management frameworks for drinking water, including the World Health Organization (WHO) through its water safety plan (WSP) framework. Two decades after the Walkerton tragedy, this paper seeks to: (i) evaluate alignment of Ontario’s Drinking Water Quality Management Standard (DWQMS) with the WSP framework (ii) review readily available data for evidence that Ontario’s DWQMS implementation has improved drinking water safety and promoted a preventive approach through …

Investigation Of Issues Concerning Wellbore Leakage, Ishtiaque Anwar

Civil Engineering ETDs

A range of applications, such as subsurface fluid storage facilities, geothermal wells, and CO2 storage wells, are concerned about leakage along wellbores. The research described in this dissertation was largely directed toward wellbore leakage concerns for the US Strategic Petroleum Reserve (SPR). For SPR wellbores, multiple fluids are likely to exist in fractures and flow paths associated with leaky wellbores, including liquids (e.g., liquid hydrocarbon - crude oil) and gases (e.g., gas ex-solved from liquid and/or nitrogen from MIT tests). Anomalous pressure records have been observed at the wellhead of SPR wellbores, indicative of wellbore leakage. In a few cases, …

Integrating Human Psychology Into Car-Following Models For Accurate Response Prediction: A Realistic Approach, Faiza Khan

Masters Theses and Doctoral Dissertations

Car-following models traditionally focus on vehicle kinematics or dynamics parameters without considering human psychology. However, recent research has attempted to incorporate psychology into car-following models. Despite these efforts, there are limitations in understanding the psychological triggers that influence individual drivers' responses. To address this gap, we propose a new car-following model based on the Theory of Planned Behavior (TPB), which incorporates a human element by utilizing concepts of psychology. To gather the data pertaining to human input a questionnaire was carefully developed utilizing the Theory of Planned Behavior. Data collection and analysis were done through a survey using google forms. …

Combining Semi-Continuous And Discrete Water Quality Data To Characterize Solute Transport, Biogeochemical Processes, And Wildfire Disturbances In Fluvial Systems, Justin Rae Nichols

Civil Engineering ETDs

In the past decade, high-frequency water quality sondes have become more abundant in watersheds across North America and Europe and are gaining a foothold in Asia and South America. In this dissertation, three relevant topics associated with high-frequency data are investigated, i.e., the impact of winter’s precipitation on surface water quality and stream metabolism, the longitudinal propagation of wildfire disturbances through a fluvial network, and the use of machine learning with high-frequency data to estimate fluvial nutrient processing. First, we found that significant snow precipitation can cause surface water anoxia and declines in stream metabolism. Second, our data illustrate that …

Towards Sustainable Water Management: Soil Analysis, Modeling, And Sensor Implementation On A Micro-Basin Chile's Los Lagos Region, Tammy N. Huynh

Civil Engineering ETDs

The Los Lagos region of Chile is experiencing ecological and socioeconomic challenges because of climate change. Despite efforts by the agricultural sector to understand and manage water resources, the lack of basic water quantification data affects their ability to effectively plan and implement water management strategies. This research aims to address this critical issue through three key objectives. First, characterize soil properties related to texture and structure in a micro-basin of the Los Lagos region. Secondly, it aims to investigate the hydrologic budget of the micro-basin with an emphasis on soil moisture using the Soil Moisture Routing model (SMR). Lastly, …

Evaluating The Feasibility Of Using Strain Measured During Sinusoidal Rate Pumping Tests To Characterize An Aquifer, Riley Blais

All Theses

Pumping tests with sinusoidal variation in pumping rate have been proposed as a method for improving aquifer characterization. These tests can interrogate a larger aquifer volume than slug tests and they can be more sensitive to small variations in drawdown. Current methods of using sinusoidal variations of rate are based on measuring pressure signals from the reservoir or aquifer, which requires access to monitoring wells. An alternative approach has been developed that measures the strain in the vadose zone instead of pressure in the reservoir. An instrument has been developed at Clemson University that can measure small strains using optical …

Healthcare Built Environment And The Covid-19 Pandemic, A Mixed-Method Study, Mohammad Saleh Nikooopayan Tak

All Theses

The outbreak of COVID-19 presented an unparalleled risk to public health, leading to urgent scientific efforts in understanding transmission mechanisms and mitigating risks, especially in healthcare settings. This mixed-methods study examines knowledge advancement regarding indoor air quality in healthcare facilities during the pandemic. A systematic literature review of 163 post-COVID studies identifies key research thrusts and 31 recommendations related to building ventilation, air filtration, surface disinfection, and monitoring. Comparison with over 200 pre-pandemic publications reveals both reliance on established infection control principles and unique contributions, such as detecting viral RNA in air and surface samples indicating potential airborne and fomite …

Water Hammer Analysis For Ash Slurry Disposal Pipelines Of A Thermal Power System, Biprodip Mukherjee, Subhasish Das, Satyapriya Mandal

Journal of Environmental Science and Sustainable Development

Coal-ash slurry transportation via pipelines has been accepted as a potential, economical, and dependable mode of two-phase flow of solid-liquid transportation. It is solid-liquid transportation where the ash slurry generally flows through mild steel, and a good amount of pump energy and pressure is required to convey the slurry with a density above 1220 kg/m3. The study is basically on the water hammer analysis of ash slurry conveying pipes. Nevertheless, since the hammer analysis is typically carried out in normal water, the study of ash slurry is compared to the know criteria of potable water. The study aims to understand …

Evaluating The Permeability Of Porous Aggregate Concrete Using Electrical Resistivity-Based Measurements, Ariel Miguel Mendez Aragoncillo

Theses and Dissertations

Recycled concrete aggregates (RCA) and lightweight aggregates (LWA) are popular alternative aggregates for concrete. However, due to their highly porous structure, concrete with RCA and LWA shows a different microstructure and higher permeability than conventional concrete. Thus, the existing relationships used to evaluate the permeability and, consequently, the durability of concrete are not applicable in concretes with RCA and LWA. This research examined the permeation properties of recycled aggregate concrete (RAC) and lightweight aggregate concrete (LWAC). The relationships between electrical resistivity-based measurements in RAC and LWAC and their permeation properties were determined and compared to that of normal weight aggregate …

Correlation Analysis Between External Damages And Transverse Load Distribution Capacit Y Of Hollow Slab Bridges, Cao Hao, Sun Dunhua, Wang Zichen, Zhao Fuli, Sun Haipeng, Xiong Wen

Journal of China & Foreign Highway

To correctly evaluate the service status of prefabricated hollow slab girder bridge, based on the measured data of apparent disease and load test of hollow slab girder bridge in reconstruction and expansion project, this paper first analyzed the data characteristics of the beam body, hinge joints, and support disease samples and obtained their statistical distribution rules. Then, according to the typical diseases (transverse cracks and hinge cracks at the bottom of the beam), the BP neural network was used to build a correlation model for them, and the close correlation between the two typical diseases of hollow slab girder bridge …

Research Of Disease Analysis And Reinforcement Technology For Typical Orthotropic Bridge Deck, Guo Fukuan, Zhou Shangmeng

Journal of China & Foreign Highway

In order to effectively solve the disease problem of orthotropic steel bridge decks, this paper relied on a steel box girder cable-stayed bridge deck reinforcement project to carry out steel bridge deck disease analysis and reinforcement technology research. The results show that the main disease of steel bridge decks is fatigue cracking. The fatigue cracks are numerous, short, and deep, and they continuously grow and cause more severe disease. The excessive fatigue stress amplitude is the main factor leading to the fatigue cracking of steel bridge decks. Once the crack occurs, the stress amplitude of the crack tip increases continuously, …

Review Of Research Progress Of Frame Beam Anchore D Structure In Slope Supporting, Zhang Junhui, Zhou Qinwei, Li Feng, Zhang Shiping

Journal of China & Foreign Highway

This paper summarized the research status of frame beam anchored structures in slope supporting and reinforcement engineering in China and abroad. It analyzed the results of structural design, model test, and field construction. Through induction and analysis, it is found that the current design of frame beam anchored structure has certain limitations, and it is necessary to form a universal design theory and method. The model test of frame beam anchored structure in slope supporting is limited by the test equipment and conditions and fails to be carried out on a large scale. The key points and standards of the …

Experimental Study On Interface Fatigue C Haracteristics Of Asphalt P Avement Pothole Patch Under External Factors, Ai Changfa, Shao Zhutao, Huang Yangquan, Ren Dongya

Journal of China & Foreign Highway

After the asphalt pavement patch for potholes is put into use, the interface joints around it are prone to fatigue and durability problems under the action of external factors such as the natural environment and driving load effect. In order to analyze the fatigue characteristics of the repaired interface joints under the action of external factors, the four-point bending fatigue test and pull-out test, combined with the results of orthogonal analysis, were used to determine the best bonding scheme of the repaired interface. The influence of external factors such as temperature, frequency, and strain level on the fatigue life of …