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Full-Text Articles in Civil and Environmental Engineering

Temporal Analysis Of Construction Safety Incidents In Southeastern U.S. Using Machine Learning Techniques, Mayowa O. Oladele Jan 2025

Temporal Analysis Of Construction Safety Incidents In Southeastern U.S. Using Machine Learning Techniques, Mayowa O. Oladele

College of Graduate Studies: Theses & Dissertations

Construction safety incidents remain a significant concern, particularly in the Southeastern U.S. due to the high-risk nature of the industry. Analyzing patterns in these incidents can help improve safety practices and reduce accidents. Machine learning (ML) techniques were employed in this study to identify temporal patterns in construction safety incidents, aiming to enhance proactive safety management. The machine learning methods used in this research included logistic regression, decision trees, random forest, support vector machine (SVM), and K nearest neighbors (KNN).

The objective of the study was to analyze temporal trends in safety incidents and identify the most effective machine learningtechnique …


Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker Jan 2025

Accelerated Test Method (Atm) For The Evaluation Of External Sulfate And Chloride Attack On Concrete Using Artificial Climate Environment (Ace): An Assessment Of Methodology, Eli Walker

College of Graduate Studies: Theses & Dissertations

This study seeks to investigate a testing methodology that utilizes accelerated testing methods (ATM) in conjunction with nondestructive testing methods (NDT) to assess destructive ion attacks on concrete. Through the testing of concrete samples, the impacts of chloride and sulfate ions on concrete will be tested by subjecting concrete to cyclic testing in an artificial climate environment. Electrical resistivity (ER) and ultrasonic pulse velocity (UPV) testing will evaluate the impact of the accelerated testing on the migration of destructive ions within the pore structure of the tested concrete. Based on this investigation, comparisons between accelerated, non-accelerated, and control samples will …


พฤติกรรมการเปลี่ยนช่องจราจรบริเวณจุดรับส่งผู้โดยสาร, ศุภวิชญ์ มัธยมนันทน์ Jan 2025

พฤติกรรมการเปลี่ยนช่องจราจรบริเวณจุดรับส่งผู้โดยสาร, ศุภวิชญ์ มัธยมนันทน์

Chulalongkorn University Theses and Dissertations (Chula ETD)

ในสภาพการจราจรจริง การไหลของกระแสจราจรมักถูกรบกวนจากยานพาหนะที่จอดเพื่อรับ–ส่งผู้โดยสาร ส่งผลให้ยานพาหนะที่ขับขี่ตามมามีสองทางเลือก ได้แก่ การรอให้ยานพาหนะด้านหน้าเคลื่อนตัวต่อไป หรือการเปลี่ยนช่องจราจรไปยังช่องที่สามารถเคลื่อนที่ได้ ซึ่งทั้งสองทางเลือกล้วนทำให้ประสิทธิภาพการไหลของจราจรลดลงเมื่อเทียบกับกรณีที่ไม่มีการรบกวนดังกล่าว ในปัจจุบัน การใช้แบบจำลองจราจรช่วยให้สามารถทำความเข้าใจและคาดการณ์สภาพการจราจรได้โดยไม่ต้องทดลองในพื้นที่จริง แต่แบบจำลองทั่วไปยังขาดความเฉพาะเจาะจงเมื่อต้องเผชิญสถานการณ์เฉพาะทาง โดยมักใช้พฤติกรรมพื้นฐานเพียงชุดเดียวในการแทนพฤติกรรมผู้ขับขี่ทุกกรณี งานวิจัยนี้มีวัตถุประสงค์เพื่อศึกษาพฤติกรรมการเปลี่ยนช่องจราจรของผู้ขับขี่เมื่อแล่นตามหลังรถที่จอดรับ–ส่งผู้โดยสาร จากนั้นนำพฤติกรรมที่ได้จากภาคสนามไปใช้ในการพัฒนาแบบจำลองสภาพจราจรใน PTV VISSIM และทำการเปรียบเทียบกับพฤติกรรมจริง ข้อมูลภาคสนามถูกเก็บรวบรวมด้วยการบันทึกวิดีโอและประมวลผลด้วย Video Analytics ก่อนนำไปสร้างแบบจำลอง ผลการศึกษาพบว่า แบบจำลองสามารถจำลองพฤติกรรมการเริ่มต้นเข้าสู่การเปลี่ยนช่องจราจรได้ใกล้เคียงกับข้อมูลจริง โดยช่องว่างเชิงเวลา (Lag Gap) ของยานพาหนะที่ขับขี่ตามมามีค่าเฉลี่ย 0.425 วินาทีในภาคสนาม และ 0.375 วินาทีในแบบจำลอง อย่างไรก็ตาม แบบจำลองยังไม่สามารถสะท้อนพฤติกรรมการเปลี่ยนช่องจราจรได้ครบถ้วนทุกด้าน ซึ่งเป็นประเด็นที่ควรได้รับการพัฒนาเพิ่มเติมในงานวิจัยอนาคต


Mitigation Of Antibiotic Resistance Using Ultraviolet Light-Emitting Diodes For Water Treatment, Nicole Heyniger, Patrick J. Mcnamara, Anthony D. Kappell, Brandon Schultz, Troy Skwor, Brooke K. Mayer Jan 2025

Mitigation Of Antibiotic Resistance Using Ultraviolet Light-Emitting Diodes For Water Treatment, Nicole Heyniger, Patrick J. Mcnamara, Anthony D. Kappell, Brandon Schultz, Troy Skwor, Brooke K. Mayer

Civil and Environmental Engineering Faculty Research and Publications

The presence of antibiotic-resistant bacteria (ARB) and antibiotic resistance genes (ARGs) in the environment is a growing issue, which has been exacerbated by the overuse and misuse of antibiotics in health care and agricultural systems. One means of mitigating antibiotic resistance is through drinking water and wastewater treatment, specifically during disinfection processes. Ultraviolet light-emitting diodes (UV-LEDs) are an emerging disinfection technology featuring adjustable peak wavelength emissions. We assessed the use of UV-LED for treating waterborne ARB (Escherichia coli and Aeromonas hydrophila) and ARGs (intracellular and extracellular) compared to conventional low-pressure UV (LP-UV). Overall, less efficient reduction (bacterial inactivation and/or gene …


Separating The Impacts Of A Corrosion Inhibitor From Copper Corrosion Products On Antibiotic Resistance In Drinking Water, Veronika Folvarska, Maya Adelgren, Emily Lou Lamartina, Ryan J. Newton, Yin Wang, Patrick J. Mcnamara Jan 2025

Separating The Impacts Of A Corrosion Inhibitor From Copper Corrosion Products On Antibiotic Resistance In Drinking Water, Veronika Folvarska, Maya Adelgren, Emily Lou Lamartina, Ryan J. Newton, Yin Wang, Patrick J. Mcnamara

Civil and Environmental Engineering Faculty Research and Publications

Antibiotic resistance is a growing threat to public health, and environmental factors, including metals in drinking water distribution systems, are increasingly recognized as contributors to the spread of antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). Zinc orthophosphate, a common corrosion inhibitor, and copper corrosion products (CuO and Cu2O) are frequently present in drinking water systems. While each has been shown to increase ARB and ARGs individually, their combined effects remain unknown. The objective of this study was to evaluate the combined impact of copper corrosion products and the corrosion inhibitor zinc orthophosphate on antibiotic resistance. Two …


Innovations In Balanced Mix Design: Establishing Gwp Thresholds For Various Nmas And Evaluating Superpave Vs. Bmd In High Content Rubber Asphalt, Kai Xin Jan 2025

Innovations In Balanced Mix Design: Establishing Gwp Thresholds For Various Nmas And Evaluating Superpave Vs. Bmd In High Content Rubber Asphalt, Kai Xin

Dissertations, Master's Theses and Master's Reports

Traditional volumetric asphalt mix design methods, such as Superpave, frequently struggle to address critical performance parameters, leading many agencies to seek more robust approaches. Balanced Mix Design (BMD) has emerged as a forward-looking alternative by directly measuring rutting and cracking resistance in the laboratory. In this study, BMD principles were applied to asphalt mixtures featuring three distinct NMAS mixes and two high content rubber mixes, introduced through both dry and semi-wet processes. Compared with conventional volumetric constraints, BMD provided greater flexibility in adjusting binder content and gradation to accommodate elevated crumb-rubber levels. The resulting mixtures satisfied both rutting and cracking …


Software Literacy In Construction, Aidan Cazares Jan 2025

Software Literacy In Construction, Aidan Cazares

Williams Honors College, Honors Research Projects

The construction industry increasingly relies on software like Bluebeam Revu for their quantity takeoff, document management, and collaboration needs. This project will outline pertinent information obtained through their Bluebeam professional training program and reflect it with a detailed estimate of a real life construct project.


Structural Analysis And Design Methodologies Of Roller Coasters, Benjamin Komar Jan 2025

Structural Analysis And Design Methodologies Of Roller Coasters, Benjamin Komar

Williams Honors College, Honors Research Projects

This project explores the structural analysis behind the design of roller coaster tracks and supports as practiced by modern engineers. It also examines various roller coaster design methods currently in use. This research will be used to craft a detailed explanation of the roller coaster design process. Additionally, a 3D model of a roller coaster was developed based on the researched design procedures, featuring three track sections with different loading conditions to create a supporting structure for 2D truss analysis. The results of the truss analysis were then compared to those obtained using RISA-3D, a finite element structural design software.


Artificial Intelligence’S Role And Impact On The Engineering Discipline, Andrew Angelini Jan 2025

Artificial Intelligence’S Role And Impact On The Engineering Discipline, Andrew Angelini

Williams Honors College, Honors Research Projects

The purpose of this Honors Research project was to explore the impact of Artificial Intelligence (AI) on the Engineering Discipline as a whole. Specifically, civil engineering’s discipline of transportation was used to display the effectiveness of AI in engineering. This discipline was used due to its wide use in engineering and overall designs that can be created within this discipline. These designs include maintenance of traffic plans, engineering plan sets, horizontal and vertical curve design, intersection design, traffic signaling, highway material design, and phasing of intersections and traffic accounting for pedestrians. Through similar prompts that were given to a publicly …


Analysis Of Lava Flow Paths Using Remote Sensing And Geomorphological Techniques, Oluwatosin Oluyemisi Ayo Jan 2025

Analysis Of Lava Flow Paths Using Remote Sensing And Geomorphological Techniques, Oluwatosin Oluyemisi Ayo

Dissertations, Master's Theses and Master's Reports

Lava flows have severe impacts on the Earth’s surface, communities, and natural habitats. Accurate modeling of lava flow paths is crucial for volcanic hazard assessment and risk mitigation. This research integrated remote sensing, geographic information systems, geomorphological techniques, and hydrologic analysis to numerically determine the optimal ground sample distance (GSD) of digital elevation models (DEMs) for delineating lava flow paths. Two volcanic regions were analyzed: the Afar Region of Ethiopia (Alu, Dalaffilla, and Erta Ale volcanoes) and the Reykjanes Peninsula of Iceland (Fagradalsfjall volcano). Forward and backward modeling methods were used to simulate potential lava flow paths. Remote sensing data, …


Data Driven Bridge Deck Deterioration Modeling And Maintenance Intervention Scheduling, Deepak Kumar Jan 2025

Data Driven Bridge Deck Deterioration Modeling And Maintenance Intervention Scheduling, Deepak Kumar

Dissertations and Theses

Majority of over 617,000 bridges across the United States are significantly impacted by environmental factors, aging materials, and heavy traffic loads. According to the 2021 Infrastructure Report, nearly 231,000 bridges require repair or preservation work, with 46,154 (7.5%) being classified as structurally deficient, thereby posing risks for mor than 178 million daily trips across these bridges. Despite recent improvements, 42% of U.S. bridges are at least 50 years old, underscoring an urgent need for increased investment to meet repair demands. The nation’s backlog of bridge repairs is estimated at $125 billion, with a 58% increase in annual spending required to …


Deep Learning Architectures For Improving Weather Research And Forecasting (Wrf) Precipitation Estimates And Landslide Susceptibility Mapping: A Case Study Of Puerto Rico, Said A. Mejia Manrique Jan 2025

Deep Learning Architectures For Improving Weather Research And Forecasting (Wrf) Precipitation Estimates And Landslide Susceptibility Mapping: A Case Study Of Puerto Rico, Said A. Mejia Manrique

Dissertations and Theses

Precipitation is a critical factor in the Earth’s hydrological cycle and has a profound impact on various environmental and socioeconomic systems, including management of water resources, flood forecasting, and the evaluation of natural hazards, particularly those associated with rainfall-induced landslides. For the latter, obtaining precise precipitation estimates is essential, as intense rainfall events can trigger landslides that pose significant risks to human life, infrastructure, and ecosystems, particularly in mountainous regions. Puerto Rico (PR), with its mountainous terrain, tropical climate, and vulnerability to hurricanes, provides a unique environment for studying precipitation patterns and the need for accurate rainfall estimates. The complex …


Design, Fabrication, & Laboratory Testing Of A Strain Gage Instrumentation System For Marine Applications, Salem C. Homrighausen Jan 2025

Design, Fabrication, & Laboratory Testing Of A Strain Gage Instrumentation System For Marine Applications, Salem C. Homrighausen

UNF Graduate Theses and Dissertations

A strain gage-based instrumentation system was designed and fabricated to measure the moment present at the base of a mock, diesel-engine snorkel for a submerged vehicle designed to operate in the surf zone. Afterwards, a lab experiment was designed and executed to determine the accuracy of the instrument and a 2-dimensional, matrix-vector equation was formulated to relate pairs of voltages, Vx and Vy, to moments, Mx and My for the experiment. Three versions of this model were built. The first model was created using traditional statics equations governing strain, stress, moment, force. The second and third models were built directly …


Assessment Of Wave Climate Conditions At An Important Historical And Ecological Site Along The Fort George River In Northeast Florida, Ally O. Kasuwi Jan 2025

Assessment Of Wave Climate Conditions At An Important Historical And Ecological Site Along The Fort George River In Northeast Florida, Ally O. Kasuwi

UNF Graduate Theses and Dissertations

This study investigated wave climate conditions at the Timucuan Preserve in northeast Florida, addressing gaps in previous shoreline erosion research that largely attributed erosion to boat wakes without detailed wave data. Field data were collected using several do-it-yourself water wave gauges. Each data collection event was for approximately one week, with an emphasis on collecting data before, during, and after periods of expected peak wave activity (i.e., holiday weekends and large-scale storms). Data were analyzed in the frequency domain to establish the likely cause of waves. Results suggested that, counterintuitively, watercraft traffic may have produced higher dominant wave periods than …


Assessment Of Surface Area Application Ratios For Beach Sand Treated Via Surface Percolated Micp-Bioslurry For Erosion Mitigation, Connor J. Marlin Jan 2025

Assessment Of Surface Area Application Ratios For Beach Sand Treated Via Surface Percolated Micp-Bioslurry For Erosion Mitigation, Connor J. Marlin

UNF Graduate Theses and Dissertations

Rapid shoreline erosion associated with sea-level rise is an ongoing threat to coastal infrastructure. Traditional stabilization techniques, such as revetments, seawalls, and periodic nourishment, often prove costly, ecologically disruptive, or provide only temporary protection. Microbially Induced Calcite Precipitation (MICP) and its operational variant, bioslurry, present a biologically inspired alternative capable of forming a cemented surface crust that reduces soil erodibility. Previous laboratory studies typically prescribed a solution dosage as a percentage of pore volume (%PV). While geotechnically sound, this metric is poorly suited to field deployment across a large area. This thesis evaluates surface-area-based dosing (L/m²) as the primary dosage …


Precast Foundation For Steel Lattice Towers, Wessam Ramadan Jan 2025

Precast Foundation For Steel Lattice Towers, Wessam Ramadan

All ETDs from UAB

Steel lattice towers are essential structures used in power transmission, telecommunications, and wind turbine towers, where they must withstand various loads to ensure stability and durability. The foundation system plays a crucial role in supporting these towers, with different types chosen based on soil conditions, environmental factors, and project requirements. Traditional foundations, such as drilled shafts, spread footings, and steel grillages have been widely used but often come with challenges, including long installation times, high labor costs, and difficult site conditions. As demand for transmission infrastructure grows, there is a need for faster, more efficient, and environmentally friendly foundation solutions. …


Geospatial Analysis For Urban Resilience: Green Space, Flood Susceptibility, And Wetland Restoration Potential, Jessica Lareaux Jan 2025

Geospatial Analysis For Urban Resilience: Green Space, Flood Susceptibility, And Wetland Restoration Potential, Jessica Lareaux

Dissertations, Master's Theses and Master's Reports

Through the integration of high-resolution geospatial data, hydrologic modeling, and spatial statistics, this research addresses three interrelated topics that are critical to sustainable, equitable, and climate-resilient urban planning. The overall objective of this dissertation is to provide data-driven and machine learning-based geospatial analysis frameworks that enhance our understanding of environmental inequities, flood exposure, and the potential for wetland restoration, with a focus on urban contexts. The study presented in Chapter Two examines the distribution and accessibility of urban green spaces in Detroit, Michigan, using high-resolution geospatial data and geospatial analysis methods, including geographically weighted regression (GWR) and network-based analyses. This …


Biopolymer-Induced Soil Ductility Enhancement: Mitigating The Effects Of Desiccation Cracks, Rabindra Prasad Bohara Jan 2025

Biopolymer-Induced Soil Ductility Enhancement: Mitigating The Effects Of Desiccation Cracks, Rabindra Prasad Bohara

Electronic Theses and Dissertations

This study addresses the formidable challenges of expansive clayey soils, notorious for their swelling-shrinkage characteristics, which often lead to ground instability and structural damage. While effective in mitigating soil swell-shrink potential and enhancing strength, traditional calcium-based stabilizers can react with higher sulfate content to form ettringite, causing volumetric changes and infrastructure distress. To assess the impact of stabilizing sulfate-rich soils and determining the various engineering properties, samples of both control and stabilized soils were prepared using lime, biopolymer (guar gum), and lime with guar gum at concentrations of 2% and 4% lime only, 0.5%, 1% and 1.5% guar gum only, …


Long-Term Assessment Of The Morphological Behavior Of The Beaches North Of Sebastian Inlet, Florida, Aidan O'Gorman Jan 2025

Long-Term Assessment Of The Morphological Behavior Of The Beaches North Of Sebastian Inlet, Florida, Aidan O'Gorman

UNF Graduate Theses and Dissertations

The morphological behavior of the beaches north of Sebastian Inlet, Florida is investigated by applying Empirical Orthogonal Function (EOF) analyses to a series of beach surveys conducted semi-annually (winter and summer) over a period of fifteen years (2005-2019), with the primary objectives being to 1) determine the extent to which the inlet’s influence to the north typically fluctuates on a short-term basis (e.g. annually), and 2) identify any long-term trends of accretion or erosion that might exist. Each survey is comprised of thirty-one cross-shore profiles that are referenced to permanently installed range monuments (“R-monuments”) that are spaced nominally 305 …


Analyzing The Safety Effects Of Edge Lane Roads For Motor Vehicle Users, John Yang Jan 2025

Analyzing The Safety Effects Of Edge Lane Roads For Motor Vehicle Users, John Yang

Master's Theses

This thesis builds upon a prior study that analyzed the safety effects of Edge Lane Roads (ELRs) within the U.S. context, addressing gaps related to collision, traffic volume, and speed data. An ELR is a roadway configuration that accommodates two-way automobile traffic within a single center lane while providing edge lanes for vulnerable road users (VRUs), i.e., bicyclists or pedestrians. Although the concept of a single shared lane for opposing traffic often raises safety concerns among the public, ELRs have demonstrated potential to control speeds, optimize roadway space, and improve traffic operations on low-volume roads.

To evaluate safety outcomes, this …


Drone-Based Multimodal Sensing On Vegetations And Data Analytics For Early Detection Of Gas Leakage From Underground Pipelines, Pengfei Ma Jan 2025

Drone-Based Multimodal Sensing On Vegetations And Data Analytics For Early Detection Of Gas Leakage From Underground Pipelines, Pengfei Ma

Doctoral Dissertations

"This study explored the feasibility of using multimodal remote sensors in the early detection of natural gas leaks from underground pipelines, as vegetation situated above pipelines can discern microbial changes in soil when affected by gas and exhibit physiological stress symptoms on leaves. Three sensors (RBG, thermal, and hyperspectral cameras) were utilized to monitor vegetation stress as an indicator of gas leaks. A laboratory experiment was conducted to evaluate the workability of vegetation for gas leak detection. Regular hyperspectral imagery was collected from test vegetations to identify gas stress and distinguish it from other environmental stressors such as salinity impact, …


Nmr Relaxometry Approach For The Detection Of Asphalt Binder Performance Properties, Rebecca Herndon Jan 2025

Nmr Relaxometry Approach For The Detection Of Asphalt Binder Performance Properties, Rebecca Herndon

Doctoral Dissertations

"Asphalt is a necessary material for transportation infrastructure. Understanding the material properties of asphalt binders is critical for improving infrastructure and enhancing the lifetime of pavements. While the physical properties of asphalt binders are well-defined by standard procedures and parameters, the chemical environment lacks definition. Physical parameters like viscosity and stiffness are traditionally used to differentiate asphalt binders, describe aging, and indicate the impact of additives. However, these tests have limited insight into the material's chemical environment. Therefore, a nondestructive analytical technique, nuclear magnetic resonance (NMR) relaxometry, was employed to investigate the chemical environment of asphalt binders. Although NMR relaxometry …


Characterization And Modeling Of Properties Of Unsaturated And Partially Damaged Cement-Based Materials, Rezwana Binte Hafiz Jan 2025

Characterization And Modeling Of Properties Of Unsaturated And Partially Damaged Cement-Based Materials, Rezwana Binte Hafiz

Doctoral Dissertations

"Transport properties, governing the resistance of cement-based materials to harmful substances are essential considerations for long-term performance. This study addressed the often-overlooked dimension of transport properties in unsaturated cement-based materials, crucial as most concrete structures face variable environmental conditions, leading to partial saturation. A two-scale model was introduced, enhancing our comprehension of transport properties in conditions reflecting real-world scenarios. Empirical correlation representing bulk paste characteristics was established, facilitating the upscaling of properties to mortar and concrete. The model was extended to predict the transport properties of mortar as well.

Environmental factors can contribute to the degradation of cement-based materials, with …


Characterizations Of Eco-Friendly Class C Fly Ash-Based Alkali-Activated Mixtures For Various 3d-Printing Techniques, Fareh Abudawaba Jan 2025

Characterizations Of Eco-Friendly Class C Fly Ash-Based Alkali-Activated Mixtures For Various 3d-Printing Techniques, Fareh Abudawaba

Doctoral Dissertations

This study explored the potential of using high-calcium class C fly ash (FA) as the main precursor for synthesizing alkali-activated mortar (AAM) suitable for 3D-printed concrete (3DPC) applications. The objective was to broaden the selection of AAMs, designed to suit various printing techniques, including continuous mixing and pumping, large batch mixing, and set-on-demand processes. The study began by assessing the fresh properties of various mixtures, utilizing tests such as open time (OT), initial setting time (IST), immediate axial deformation, and penetration test (PT), to determine the mixtures' extrudability and buildability. The study optimized mixtures with a broad spectrum of cycle …


Groundwater Pumping Impacts On Stream Depletion In Humboldt County, Ca: Integrating Analytical Models And Field Data, Andy Hans Heise Jan 2025

Groundwater Pumping Impacts On Stream Depletion In Humboldt County, Ca: Integrating Analytical Models And Field Data, Andy Hans Heise

Cal Poly Humboldt theses and projects

This study addresses the significant concern of stream depletion from groundwater pumping in Humboldt County, CA. The objective of this study is to develop an analytical model for estimating stream depletion and integrating field data into model parameters.

The methodology involved conducting a field study near three operating wells by a stream, installing stream gages upstream and downstream of the wells, and recording pumping rates and schedules for two of the wells. The third well’s pumping data was synthetically generated, for privacy concerns of the well owner. The StreamDepletR package was used for estimating depletion rates in a stream in …


An Analysis Of Uv Disinfection Of Municipal Wastewater Following Natural Treatment Systems, Jonathan Andrew Kirchubel Jan 2025

An Analysis Of Uv Disinfection Of Municipal Wastewater Following Natural Treatment Systems, Jonathan Andrew Kirchubel

Cal Poly Humboldt theses and projects

On January 30, 2024, the City of Arcata replaced chlorine with ultraviolet (UV) irradiation as its disinfection method for treating its wastewater prior to discharging to Humboldt Bay. The Arcata wastewater treatment facility (AWTF) utilizes natural treatment systems for treating its secondary effluent, which can provide issues for UV disinfection through variance in turbidity, total suspended solids (TSS), pH, humic acids, and color. This project aimed to identify whether the water quality characteristics of natural treatment systems in the AWTF would impact UV disinfection of municipal wastewater.

Thirty-one sampling periods occurred between June 8, 2024, and March 1, 2025, recording …


Effects Of Peel Angle And Strain Rate On The Bond Between Frcm Composite And Concrete Substrate, Lucas Robert Gervais Jan 2025

Effects Of Peel Angle And Strain Rate On The Bond Between Frcm Composite And Concrete Substrate, Lucas Robert Gervais

Electronic Theses and Dissertations

Fiber-reinforced cementitious matrix (FRCM) composites have gained increasing attention for the rehabilitation and strengthening of concrete and masonry structures due to their favorable mechanical properties, compatibility with existing substrates, and ease of application. The effectiveness of any strengthening procedure depends on the quality of the bond between the external reinforcement and the substrate, ensuring efficient stress transfer and enabling the system to reach its ultimate capacity without premature debonding. While research has focused on the bond performance of FRCM systems under pure shear loading and quasi-static, low strain rate conditions, the effects of mixed-mode loading and high strain rates representative …


Influence Of Deck Area And Average Daily Traffic On The Deterioration Of Bridge Superstructures., Faysal Ahamed Jan 2025

Influence Of Deck Area And Average Daily Traffic On The Deterioration Of Bridge Superstructures., Faysal Ahamed

Graduate Theses, Dissertations, and Problem Reports (ETD)

State Departments of Transportation (DOTs) are responsible for maintaining approximately 623,000 bridges across the United States. Effective bridge management requires a comprehensive understanding of the factors influencing structural deterioration. Numerous studies have explored the effects of average daily traffic (ADT) and deck area (DA) on bridge deck deterioration. Given the interdependence between bridge decks and superstructures, it is plausible that ADT and DA significantly influence superstructure condition ratings and deterioration trends. However, their impact on superstructures remains insufficiently studied. In addition, existing studies primarily focus on overall bridge deterioration without adequately differentiating between superstructure designs and materials and maintenance authorities. …


Reuse Of Calcium Carbonate (Caco3) Recovered From Discarded Carpets As Filler In Fiber-Reinforced Polymer (Frp) Composites, Roshan Devkota Jan 2025

Reuse Of Calcium Carbonate (Caco3) Recovered From Discarded Carpets As Filler In Fiber-Reinforced Polymer (Frp) Composites, Roshan Devkota

Graduate Theses, Dissertations, and Problem Reports (ETD)

Over four billion pounds of carpet are discarded annually in the United States, making carpet waste a significant environmental concern. Calcium carbonate (CaCo₃) constitutes up to 45% of the mass of most synthetic carpets. Reusing this CaCo₃ as a filler in the rapidly growing fiber-reinforced polymer (FRP) industry, which is projected to reach USD 10.38 billion, presents a low-cost, practical approach to developing a market-based solution to post-consumer carpet waste.

This study investigates the reuse of CaCo₃ recovered from discarded carpet backing as a filler in FRP composites, focusing on its mechanical viability in comparison to virgin CaCo₃. The methodology …


Recovery Of Iron And Aluminum From Acid Mine Drainage For Beneficial Uses, Katelyn Renee Pepe Jan 2025

Recovery Of Iron And Aluminum From Acid Mine Drainage For Beneficial Uses, Katelyn Renee Pepe

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid mine drainage (AMD) is a widespread issue across the globe, in which some of the most critical cases are created by the mining industry. Researchers have investigated ways to derive benefits from AMD, such as precipitating rare earth elements (REEs) to generate potential revenue from AMD treatment and supplement market demand. However, the bulk of precipitated sludge is composed of iron and aluminum, which also have market value but are discarded in current practice.

Using the Omega site in West Virginia (WV) as a representative AMD source, the objectives of this study are (1) to determine a replicable precipitation …