Other Civil and Environmental Engineering Commons^™

Linear Generators In Wave Energy Conversion: Performance, Feasibility, And Location Study, Luis Fernandez De Valderrama

UNF Graduate Theses and Dissertations

As the energy demand increases and climate change becomes a major problem, the solution to decrease greenhouse gas emissions and mitigate the effects of climate change involves increasing the use of sustainable and renewable sources to generate electricity. However, developed renewable sources have inconveniences that make them incapable of generating the totality of the electricity that a country demands. Wave energy is an alternative renewable energy source that can help mitigate the inconveniences of other renewable sources and decrease the emission of greenhouse gases.

This study aims to find the potential of linear generators in wave energy by analyzing the …

Predicting Anthropogenic Underwater Pile Driving Noise Using Pile Driving Analyzer (Pda) Data, Brandon Alfredo Rivera

UNF Graduate Theses and Dissertations

In the past several years, there has been increasing concern about anthropogenic noise generated during marine pile driving. This concern is expected to increase concomitantly with increases in waterfront construction efforts associated with aging infrastructure and sea level rise. Several guidelines are available to help predict underwater noise transmission due to pile driving, but the issue with all these methods is that they require one to measure sound pressure levels at one locus or more from the driven pile. In the context of marine construction, adding specifications for underwater noise collection may be expensive or difficult because contractors typically have …

Modeling Coastal Vulnerability Of The St. Johns River And Northeastern Florida Shorelines, Madison E. Heppe

UNF Graduate Theses and Dissertations

Coastal and riverine communities, with anthropogenic congestion and natural and economic resources, are vulnerable to climate change impacts including rising sea levels and increasing severity and frequency of storms. Coastal habitats are being increasingly recognized as natural infrastructure that provides resiliency against these stressors. However, few studies have analyzed coastal vulnerability at landscape scale with finely resolved spatial data that account for habitats and demographics. The purpose of this study is to map the coastal vulnerability of the St. Johns River and adjacent Northeastern Florida Atlantic shoreline within the St. Johns River Water Management District. Unique to this study is …

Estimating A Range Of Flow Rates Resulting From Extreme Storm Events Within The Wekiva River Watershed Through Statistical Testing And Modeling, Wesley K. Koning

UNF Graduate Theses and Dissertations

The middle portion of the St. Johns River is located in East-Central Florida, USA. This region of the St. Johns River is increasingly subject to urbanization and conversion of forest areas to agricultural land. Overall, these changes mean that future flood events in the area could adversely impact local citizens. Therefore, the examination of extreme flood events and resiliency to such events is critical. The purpose of this preliminary study is to explore a range of practical applications to estimate extreme flood flows at watercourses within the Middle St. Johns River Basin, focusing specifically upon the Wekiva River sub-basin. The …

A Computational Analysis Of Marine Fenders Under Heavy Weather Mooring Conditions, Zachary Eskew

UNF Graduate Theses and Dissertations

Dynamic loading of marine fenders is a situation that is unique to the United States Navy (USN), due to the use of Heavy Weather Mooring (HWM) for naval vessels during extreme weather events, such as hurricanes. Traditional analysis has not been concerned with the fender reaction on vessel hulls. However, newer classes of Naval ships, such as the Littoral Combat Ships (LCS), have designs that emphasize speed and agility, resulting in them having thinner hulls more susceptible to damage from fenders. In traditional analysis, fenders are modeled as idealized springs, with static- load derived spring constants from manufacturer charts. This …

Testing Coulwave For Use In Modeling Cross-Shore Sand Transport And Beach Profile Evolution, Patrick Michael Cooper

UNF Graduate Theses and Dissertations

Realistic, reliable, and effective modeling of cross-shore sediment transport is not present in the current literature. Building that model requires the accurate recreation of breaking wave processes in the nearshore. To develop that first step for an as-yet-to-be-designed model, multiple phase-resolving wave transformation algorithms are reviewed for in-depth investigation. The COULWAVE model is selected for robust testing. Testing of the COULWAVE model shows that, although capable of recreating realistic results, it does not adequately describe major wave characteristics in the surf zone, across a wide range of conditions, to warrant use in a future cross-shore sediment transport model.

A Study On Erosion Resistance For Microbially Induced Calcite Treated Beach Sand, Abigail Chek

UNF Graduate Theses and Dissertations

Microbial induced calcite precipitation (MICP) was used to treat several sandboxes filled with naturally occurring beach sand collected from Atlantic Beach, FL. Unlike most previous MICP studies, a surface-spray technique was used to treat these sandboxes where relatively high-concentration bacteria solution and high concentration calcium chloride/urea solutions were applied directly to the boxes’ surfaces. Several different treatment combinations were tested whereby bacterial optical density, bacteria/urea/calcium chloride volume relative to void space, and bacteria/urea/calcium chloride ratio were manipulated. Treated sandboxes were tested for erodibility using a pocket erodometer and for calcification using a wash method. In addition, sandboxes were dissected after …

An Analysis Of Hydroacoustic Transmission Loss Associated With Marine Pile Driving, Jonathan Paul Berube

UNF Graduate Theses and Dissertations

There has been a growing concern in recent years about the effects of anthropogenic noise due to marine pile driving on underwater wildlife. Current guidelines for mitigating hydroacoustic effects associated with these events are based upon relatively simple transmission loss formulations. The advantage to these guidelines is that computing transmission loss using their prescribed methods is not labor intensive, but their disadvantage is that they may not take all variables into account. Because of this, it may be possible to improve transmission loss computations. To better-characterize marine pile driving sound transmission loss, a unique in-water instrumentation system was developed. This …

Effect Of Vessel-Generated Waves In Near Low Tide Conditions On Shorelines In The Intracoastal Waterways, Mackenzie Lee Sanchez

UNF Graduate Theses and Dissertations

Erosion is caused when there is a net loss of sediment in a coastal system, i.e. when the amount of sediment leaving a system is more than the amount of sediment entering that same system. This investigation will focus on vessel-generated waves and their effect on the shorelines of the Jacksonville, Florida Intracoastal Waterways near low tide conditions. The investigation conducted herein examines variations in turbidity and pressure measurements in response to passing vessels at a single site location previously selected in 2016. The primary water/shoreline interaction recorded during this investigation is located below the visible scarp (near low tide …

Particle Filters For State Estimation Of Confined Aquifers, Graeme Field

UNF Graduate Theses and Dissertations

Mathematical models are used in engineering and the sciences to estimate properties of systems of interest, increasing our understanding of the surrounding world and driving technological innovation. Unfortunately, as the systems of interest grow in complexity, so to do the models necessary to accurately describe them. Analytic solutions for problems with such models are provably intractable, motivating the use of approximate yet still accurate estimation techniques. Particle filtering methods have emerged as a popular tool in the presence of such models, spreading from its origins in signal processing to a diverse set of fields throughout engineering and the sciences including …

An Integrated Closed Convergent System For Optimal Extraction Of Head-Driven Tidal Energy, Michelle Ann Vieira

UNF Graduate Theses and Dissertations

As the demands for energy increased with the global increase in population, there is a need to create and invest in more clean and renewable energy sources. Energy derived from the movement of the tides is an ancient concept that is currently being harnessed in a handful of large tidal range locations. However, the need to move from fossil fuel driven energy sources to those that are clean and non-polluting is a priority for a sustainable future. Globally, hydropower potential is estimated to be more than 16,400-Terawatt hours annually. Given that the electricity consumption worldwide was at 15,068-Terawatt hours in …

A Novel Design To Harness Water-Wave Energy, Abdallah El Safty, Abdallah Walid El Safty

UNF Graduate Theses and Dissertations

Renewable energy sources are essential to our future, not only because they generally minimize harm to our environment but are also a relatively free source of energy that are available for generations to come. Wind and solar energy are proven sources of renewable energy, but both are highly variable. On the other hand, water wave energy is relatively persistent in locations around the world. Many researchers have tried to capture the energy of ocean waves, some were successful, but most were not. Harnessing wave energy is not a simple matter. One must design systems that can withstand the extreme forces …

The Role Of Wave Self-Similarity In Nearshore Wave Spectra, Morgan M. Smith Mr.

UNF Graduate Theses and Dissertations

Nonlinear wave-wave interactions and wave breaking contribute to nearshore wave energy dissipation. These factors can be analyzed by the principles of wave self-similarity. The equilibrium range can be shown in wind-driven wave spectra that exist in the form ( ) and However, the appropriate methods used to determine this loss of energy are controversial. This study examines an approach that reinvestigates the self-similarity principles. Wave spectra with lower peak periods are dominated by nonlinear wave-wave interactions which produce a scaling in shallow water. This thesis investigates the relative role of spectral similarity in different conditions in the nearshore region of …

Investigation Of Near-Bottom Current Characteristics Along An Open-Ocean Coast, Nikole S. Ward

UNF Graduate Theses and Dissertations

Near-bottom current data was collected over a period of 8 years at the U.S. Army Corps of Engineers Field Research Facility in Duck, North Carolina. This data set consisted of currents measured up to three elevations above the bottom at deployment depths of 5 meters, 8 meters and 13 meters, as well as continuous real-time wind and wave data collected at the pier. The data was collated, quality checked and analyzed to define a climatology of near bottom currents along the study area using current moments. This data set had previously never been available for analysis due to the large …

The Simulation & Evaluation Of Surge Hazard Using A Response Surface Method In The New York Bight, Michael H. Bredesen

UNF Graduate Theses and Dissertations

Atmospheric features, such as tropical cyclones, act as a driving mechanism for many of the major hazards affecting coastal areas around the world. Accurate and efficient quantification of tropical cyclone surge hazard is essential to the development of resilient coastal communities, particularly given continued sea level trend concerns. Recent major tropical cyclones that have impacted the northeastern portion of the United States have resulted in devastating flooding in New York City, the most densely populated city in the US. As a part of national effort to re-evaluate coastal inundation hazards, the Federal Emergency Management Agency used the Joint Probability Method …