Engineering Commons^™

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

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

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 …

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 …

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 …

Experimental And Simulation Of Compression After Impact (Cai) Tests For Thermoplastic Composite Materials, M. M. Shahzamanian, Sydney Houck, Li Ai, Md Mushfiqur Rahman Fahim, Sourav Banerjee, Wout De Backer, Paul Ziehl

Civil Engineering Faculty Publications

Damage caused by low velocity impacts in composite materials may go undetected, resulting in significant damage being unnoticeable. This phenomenon has been studied using experiments and simulations on a typical composite material, Toray T1225 LM-PAEK UD Tape, following impacts with varying energy levels. To the authors’ knowledge, there is a lack of information on thermoplastics and compression after impact (CAI) in the publicly available literature, and there have been insufficient results and discussions regarding CAI tests on thermoplastic composite materials at the relatively high levels of impact used, especially with the rise in the use of thermoplastic materials for the …

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 …

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 …

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 …

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 …

Prioritizing Amd Impaired Watersheds For Watershed-Scale Restoration Using Multi-Criteria Decision Analysis, James Nicholas Marino

Graduate Theses, Dissertations, and Problem Reports (ETD)

Acid Mine Drainage (AMD) remains a significant environmental challenge in coal-mining and hard rock regions like West Virginia, degrading water quality and ecosystem health. Traditional site-specific remediation efforts often prove inefficient in addressing AMD at large scale. This study explores watershed-scale restoration as a more effective solution, leveraging centralized treatment facilities and multi-source pollution management. This study will follow Multi-criteria Decision Analysis (MCDA), specifically the Analytical Hierarchy Process (AHP), to develop a structured rubric for grading watersheds. The process involves identifying critical criteria, organizing them into a hierarchy, and generating weights for clusters of criteria through collaboration with decision makers. …

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. …

Quantifying Subsurface Pavement Temperatures Subject To Future Climates And Implications For Pavement Resilience, Austin Michael Jarrell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Assessment of anthropogenic climate change impacts in pavement design and analysis remains limited within engineering practice, despite growing recognition of the need for climate-resilient roadway infrastructure. Research efforts have increasingly focused on integrating future climate projections into mechanistic-empirical pavement design, which represents the leading edge of the state of practice. However, a lack of consensus persists regarding the optimal methods for incorporating climate projections, particularly in the selection of downscaling techniques and global climate models (GCMs) to ensure accuracy and applicability for pavement performance analysis. This research investigates the impact of statistical downscaling methodologies and GCM selection routines on subsurface …

In-Plane Shear Stiffness Of Stay-In-Place Forms And Bracing Effects On The Torsional Stability Of Press-Brake-Formed Tub Girders, Ethan L. Host

Graduate Theses, Dissertations, and Problem Reports (ETD)

Press-brake-formed tub girders have welded internal angle bracing that is believed to be necessary for torsional stability under eccentric loading. However, this bracing creates fatigue weld hotspots overtime, which are subject to cracking. This study was performed to assess the torsional behavior of the Valmont U12 press-brake-formed tub girder (PBFTG) under various configurations using finite element analysis (FEA) modeling and experimental laboratory testing. The primary objective was to (1) determine the necessity of various angle bracing throughout the beam, and the effects removing said braces has on the torsional stiffness of the girder and (2) investigate the use of stay-in-place …

Assessing The Environmental Impact Of Municipal Solid Waste, Ojo Oluwayinka Florence, Olaniyan Olatunji Sunday, Akolade Adebola Saheed, Alabi Oluwaseyi Omotayo, Olaomotito Precious Adesope, Adebayo Kehinde John

Journal of Environmental Science and Sustainable Development

Municipal solid waste (MSW) management presents significant environmental challenges, especially with increasing urbanization and population growth. This study assesses the environmental impacts of MSW, focusing on waste composition, management practices, and their effects on air, water, and soil quality. The primary objective is to evaluate how MSW contributes to environmental degradation and to explore strategies for mitigating these impacts. A hypothesis was developed that optimizing waste composition through proper sorting and treatment can reduce the environmental footprint of MSW management by at least 10% in terms of leachate production and greenhouse gas emissions. Samples were collected using a randomized sampling …

Road Safety Assessment For Accident And Non-Accident Cases Supporting Sustainable Development Goals 2030, Brian Nararya Nugraha, Sekar Warangi Nurcahyati, Hizkia Adhikaratma, Martha Leni Siregar

Journal of Environmental Science and Sustainable Development

Halving the number of global deaths and injuries from road traffic accidents is one target of the Sustainable Development Goals 2030, which is still a challenging problem in Indonesia. However, the majority of research on this topic uses accident-based methods, which limits the safety analysis. Two road safety assessment methods are used to close the gap, with the addition of non-accident-based methods such as Road Safety Audits (RSA). The Margonda Raya Road, which is categorised as a traffic accident blackspot, was selected for the case study. For this, a field survey of the road segment is carried out. To minimise …

Metakaolin-Based Geopolymer Concrete; Synthesis, Development And Characterization, Heba Fouad

Theses and Dissertations

Geopolymers are rendered as an essential sustainable replacement to the widely used Ordinary Portland Cement (OPC) which causes immense carbon dioxide emissions, hence a detrimental impact on society’s health and the environment. Geopolymers are three-dimensional networks of polymerized tetrahedral silicate and aluminate in the form of Q4(4Al), Q4(3Al) and Q4(2Al) which act as the principal binding phase in concrete. Past research has reported the synthesis of geopolymers from different aluminosilicates precursors, their characterization, and their wide range properties. However, previous studies still have not properly investigated effective range of synthesis ratios for a particular source material, optimum curing regimes, short- …

Experimental Insights Into Friction Losses Of Post-Tensioned Precast Full-Scale Girders, Mostafa Serry

Theses and Dissertations

The use of post-tensioning in construction has revolutionized the construction industry and made way for several construction and structural applications that were unattainable before. One of the most important topics that are synonymous with the use of post-tensioning is the matter of accurately calculating the short-term and long-term losses that arise in pre-stress. One of the prominent types of losses is the friction losses that occur during the jacking of the concrete elements due to its impact on structural integrity and longevity.

The thesis examines this critical aspect of friction losses in post-tensioned concrete structures. The study focuses on full-scale, …

Strategic Knowledge Management Framework For Technology Transfer In Indonesian Joint Operation Construction Projects, Yudha Trimuliadi Suryana, Ayomi Dita Rarasati

CSID Journal of Infrastructure Development

Joint Operation (JO) construction companies in Indonesia face persistent challenges in technology transfer, including misalignment between advanced technologies and organizational capacities. Knowledge management has been proposed as a strategic solution, but its implementation remains underdeveloped. This study develops a framework to enhance technology transfer in JO construction projects through improved knowledge management practices. Utilizing a mixed-methods approach, the research combines a literature review with an analytical hierarchy process, fuzzy set theory, and a simple additive weighting method, supported by data from selected respondents involved in the Jakarta Mass Rapid Transit (MRT) project (CP201). Key findings identify knowledge acquisition, utilization, and …

Sloshing Analysis Of An Isothermal Fluid In A Cylindrical Tank For Cryogenic Tank Design Using Smoothed Particle Hydrodynamics, Dillon Freeman

The Plymouth Student Scientist

This paper investigates the capability of Smoothed Particle Hydrodynamics to model the free surface sloshing response of an isothermal fluid in a cylindrical geometry. Eleven frequencies for two horizontal driving amplitudes (0.5 mm & 2.0 mm) were validated against experimental results and the influence of the starting direction of the tanks acceleration on the steady state response was investigated. The SPH results reproduced the overall behaviour of the experimental data closely over the range of frequencies tested, but produced higher amplitudes with greater variance in the region of the tanks natural frequency. Furthermore good symmetry was observed between sidewalls for …

Enhancing Concrete Sustainability With Self-Healing Technologies, Al Shimaa Abdullatif

Theses and Dissertations

Thanks to its strength, durability and affordability, Portland cement concrete is the most commonly used building material worldwide. However, concrete cracking is inevitable due to numerous factors including shrinkage, exposure to external chemicals, internals reactions, excessive loads, to name but a few. Self-healing is a promising technique that can enable concrete to autogenously heal cracks and alleviate much of the damage. Such healing can without a doubt extend the service life with less need for external repair works therefore it contributes to sustainability. Over the years, several means of self-healing agents have been explored including bio-based procedures and the incorporation …

Real-Time Control (Rtc)-Based Urban Flood Risk Assessment Framework For Arid And Semi-Arid Regions, Sulaiman Altami

Dissertations - ALL

Global climate change has recently increased Flood Risk (FR) disasters in arid and semi-arid regions, particularly in Gulf countries, such as the Kingdom of Saudi Arabia (KSA). Arid regions generally face low rain on average during a year, but flash floods occur during rainfall of longer return periods due to urbanization and climate change. Flood Risk Assessment (FRA) outcomes enable municipalities (planners and decision-makers) in arid urban areas to develop flood management strategies and mitigate the issues of drainage systems, which may otherwise affect the quality of life. FRA is an effective tool for not only identifying high-risk areas but …

The State Of The City's Bridges, Leo G. Miranda

Capstones

An analysis by NYCity News Service of 2024 federal bridge inspection found that 118 segments of city bridges are in poor condition, around 8% of all bridges citywide. Among these are segments of major highways and bridges like the Brooklyn Queens Expressway, FDR Drive, Harlem River Drive, Grand Central Parkway and even a part of the iconic Brooklyn Bridge. On a single stretch of highway, where the Grand Central Parkway and the Whitestone Expressway meet in Queens, there are seven parts of highway or ramps in poor condition.

Bridge segments can be any raised roadway that passes over another parkway, …

Physics-Based And Data-Driven Constitutive Modeling Of Unsaturated Soils Under Multi-Physics Loading Conditions, Mohsen Ajdari

Theses and Dissertations

Understanding the behavior of unsaturated soils under multi-physics loading is crucial for addressing several challenges related to emerging geo-energy technologies, climate change, and geohazard mitigation. The main objective of this research is to enhance the state of the art for modeling unsaturated soils under multi-physics loading conditions through physics-based and data-driven approaches. Toward this objective, this dissertation is divided into two distinct yet interrelated parts. In the first part (Chapters 2, 3, and 4), thermodynamic principles are employed to develop new constitutive functions to describe soil suction and stress-dilatancy of unsaturated soils under temperature-dependent conditions. Building upon the insights gained …

Assessing Plate Load Testing And Modulus Of Subgrade Reaction Determination For Pavements, Jami Lynn Rushing

Theses and Dissertations

This thesis aims to: 1) determine the effect of plate size on the modulus of subgrade reaction (k), 2) investigate the differences between the ASTM D1196-21 and CRD-C 655-95 plate load test methods, and 3) develop new effective k curves. 150 plate load tests were executed on three subgrade materials under varying base course thicknesses. Plate load testing was designed to evaluate various plate sizes and testing standards (e.g., the military standard – CRD-C 655-96 and the ASTM standard – ASTM D1196-21). By performing plate load tests on varying base course thicknesses, newly developed effective k curves were developed from …

The Plastics Crisis: Responsible Recycling In Civil Engineering And Infrastructure, Jason Howell Stewart

Theses and Dissertations

A global plastics crisis exists with around 400 million metric tons (MMT) of plastics production and 350 MMT of plastics waste generated annually around the globe. Plastics are durable and essentially non-biodegradable, so they accumulate in both terrestrial and marine environments as pollution and within landfills without breaking down over time. Plastics are ubiquitous in 21st-century society and culture, comprising essential elements in most industries including packaging, transportation, electrical/electronics, and building/construction. The role of civil engineering and infrastructure in addressing the plastics crisis was specifically explored. Responsible plastics recycling yields products with improved engineering properties, performance characteristics, marketability, and/or manufacturing …

A Case Against Exclusive Reliance On Volumetric Mixture Characterization For Future Asphalt Pavements And The Advancement Of A Viable Alternative, Jonathan Randy Easterling

Theses and Dissertations

Volumetric properties have been the cornerstone of asphalt mixture design and control dating back to the early 20th century. However, social and economic drivers have caused the asphalt industry to make changes in materials and processes used to produce mixtures that have stretched the limits of volumetric centric methodologies. The primary objectives of this dissertation were to present an extensive case on how volumetrics is limited in their ability to characterize asphalt mixtures and to advance the body of knowledge of a viable alternative. State agency specifications were examined and found that Departments of Transportation (DOTs) were using asphalt volumetric …

Enhanced Wind Velocity Imputation Near Building Structures Using Advanced Machine Learning Techniques, Istiak Ahammed, Sujeen Song, Gang Hu, Jinwoo An, Bubryur Kim

Civil Engineering Faculty Publications

The evaluation of instantaneous wind flow patterns nearest to building architecture is crucial to ensuring structural stability, architectural integrity, and pedestrian safety. Particle image velocimetry (PIV), a technique for studying fluid flow by tracing particles, provides accurate predictions of instantaneous wind velocities (IWV). However, PIV encounters challenges in specific regions due to laser light-based experimentation, leading to missing data. Consequently, investigating the wind circulation pattern around buildings becomes more challenging. Numerous ML techniques have been employed to impute missing wind velocities at random building locations with minimal structural impact. This paper focuses on addressing this concern by utilizing a machine …

Enhancing Civil Infrastructure Performance Through Lidar-Based Dynamic Monitoring And Phased-Construction Bridges, Khalid Hossam Alkady

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation aims to enhance the performance and structural integrity of civil infrastructure systems through two primary goals. The first goal is to develop and rigorously validate end-to-end frameworks for full-field monitoring of the dynamic response of civil structures via Ground-based Lidar (GBL) scanners. GBL can be employed to sample point clouds at a high sampling rate for dynamic data collection, which addresses the limitations of using contact-based sensors in structural health monitoring (SHM) applications used for early-detection of structural damage.

The second goal of this dissertation concerns the challenges associated with constructing bridges in phases, so they can remain …

Increasing Drift Capacity Of Non-Ductile Concrete Shear Walls Through Confinement With Fiber-Reinforced Polymer Application, Andrew Duong, Sophia Maglabe, Sheyna Rongong

Architectural Engineering: Graduate Reports

The seismic response and laboratory testing of pre-1980s reinforced concrete (RC) shear walls commonly exhibit undesirable concrete crushing and rebar buckling in the wall end-zones leading to a flexural compressive failure. The lack of ductility of these walls is attributed to low reinforcement ratios and absence of special boundary elements (SBE) as required by modern design code. Thus, the authors are proposing a fiber reinforced polymer (FRP) retrofit method to provide confinement to the end-zones of pre-1980s walls equivalent to that of an SBE. Current industry applications of FRP have largely been for shear strengthening of RC beams, columns, and …