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Microfluidic Pore Model Study On Physical And Geomechanical Factors Influencing Fluid Flow Behavior In Porous Media, Shuang Cao

LSU Doctoral Dissertations

Fluid flow in porous media is a subject of fundamental importance and relevant to numerous engineering applications. The comprehensive description of fluid interaction parameters containing wetting properties, fluid-fluid displacement ratio, and capillary pressure, are inevitably needed. Moreover, the fine-grained sediments’ response to various pore fluids and migration in porous media influences reservoir geomechanical properties and pore clogging is essential to a better understanding of fluids flow behavior.

This dissertation provides a detailed study of physical and geomechanical factors influencing fluids flow behavior in porous media. The two-dimensional micromodel tests have been conducted under a wide selection of fluids flow conditions. …

Multi-Hazard Performance Assessment Of High-Rise Buildings, Jad El Khoury Antoun

LSU Master's Theses

In the last few decades, there has been an important increase in building high-rise constructions in many cities around the world. Since they offer several benefits in populous areas in terms of space efficiency, economy and sustainability, tower buildings attracted practitioners and researchers to understand better their exclusive behavior and response to natural hazards (e.g., hurricanes, earthquakes). Because of their flexibility and their commonly limited damping, skyscrapers are more susceptible to wind and earthquake actions than low- and mid-rise buildings. Moreover, many locations are prone to multiple hazards; hence, it is important to understand thoroughly the structural behavior of structures …

Field Investigation And Performance Evaluation Of Interface Bonding Between Pavement Layers, Ramendra N. Das

LSU Master's Theses

Proper bonding between pavement layers is essential to provide a monolithic pavement structure that allows distribution of loading over a larger area. Inadequate interface bonding may cause debonding or shear failure at the interface due to the accumulation of concentrated tensile stresses at the bottom of the overlay. Tack coat, a light application of asphaltic cement emulsion is applied on the existing surface to create a strong adhesive bond between pavement layers. The objectives of this study are to investigate the effects of various factors affecting bond strength between hot-mix asphalt (HMA) overlay and underlying pavement layers in the field. …

Development Of Artificial Intelligence Approach To Nowcasting And Forecasting Oyster Norovirus Outbreaks Along The U.S. Gulf Coast, Shima Shamkhali Chenar

LSU Doctoral Dissertations

Oyster norovirus outbreaks pose increasing risks to human health and seafood industry worldwide. This study presents an Artificial Intelligence (AI)-based approach to identifying the primary cause of oyster norovirus outbreaks, nowcasting and forecasting the growing risk of oyster norovirus outbreaks in coastal waters. AI models were developed using Artificial Neural Networks (ANNs) and Genetic Programming (GP) methods and time series of epidemiological and environmental data. Input variable selection techniques, including Random Forests (RF) and Forwards Binary Logistic Regression (FBLR), were used to identify the significant model input variables among six independent environmental predictors including water temperature, solar radiation, gage height, …

Sustained Flow Index: A Stochastic Measure Of Freeway Performance, Siavash Shojaat

LSU Doctoral Dissertations

The capacity of a road addresses its quantitative traffic carrying ability. The estimation of capacity as a parameter to assess traffic flow performance on freeway facilities has received considerable attention in the literature. Research into the traffic operation at high volumes reveals that the capacity of freeways is not a fixed number, but rather a random variable. Thus, in a stochastic approach to freeway capacity of estimation, the capacity is treated as a random variable generated from a population of flow observations, stemmed from a certain distribution function. Since the type of capacity distribution function is generally not known with …

An Enhanced Bridge Weigh-In-Motion Methodology And A Bayesian Framework For Predicting Extreme Traffic Load Effects Of Bridges, Yang Yu

LSU Doctoral Dissertations

In the past few decades, the rapid growth of traffic volume and weight, and the aging of transportation infrastructures have raised serious concerns over transportation safety. Under these circumstances, vehicle overweight enforcement and bridge condition assessment through structural health monitoring (SHM) have become critical to the protection of the safety of the public and transportation infrastructures. The main objectives of this dissertation are to: (1) develop an enhanced bridge weigh-in-motion (BWIM) methodology that can be integrated into the SHM system for overweight enforcement and monitoring traffic loading; (2) present a Bayesian framework to predict the extreme traffic load effects (LEs) …

Development Of A Mode And Destination Type Joint Choice Model For Hurricane Evacuation, Ruijie Bian

LSU Doctoral Dissertations

Since Hurricane Katrina, transit evacuation service has been seen to serve critical needs in affected cities and an increasing number of hurricanes have struck the east coast where more people rely on public transportation to evacuate. Thus, it is important to model mode choice in evacuation for a better estimation of evacuation transit demand. In this study, a joint mode and destination type choice model was estimated based on multiple post-storm behavioral surveys from the northeastern seaboard to the Gulf coast. A Nested Logit model specification was used to estimate this joint choice model. The estimated model showed significant linkage …

Numerical Evaluation Of The Lateral Behavior Of Vertical And Battered Pile Group Foundations Using 3-D Finite Element Modeling, Ahmad Souri

LSU Doctoral Dissertations

The design of pile foundations to resist lateral loads is essential in offshore structures and bridge foundations. The lateral behavior of piles has been studied in the past by experimental investigations coupled with analytical and numerical methods. The problem is complex due to the nonlinearities from soil behavior, gap formation, and pile-soil-pile interaction in pile groups (or the group effect). In this work, the finite element (FE) modeling was used to study the lateral behavior of pile groups. The FE method is robust and allows incorporating the necessary aspects for studying the behavior of pile groups. The nonlinear material behavior …

Application Of Surface Treatments To Improve Fuel Efficiency Of Internal Combustion Engines, Amirabbas Akbarzadeh

LSU Master's Theses

To improve the tribological performance of contacting surfaces, different surface modification methods can be employed. Surface texturing and surface coating are examples of viable techniques developed for this purpose. Surface texturing involves creating micropatterns on the contacting surfaces while surface coating requires depositing a thin layer of a suitable material on the surface(s) to improve the component’s friction and wear characteristics. The performance of textured surfaces is affected by the geometric characteristic of textures.When dealing with surface coating parameters, the parameters of interests are the type of coating materials and their thicknesses.

The current study aims to experimentally study the …

Optimizing Stabilized Fluorogypsum To Decrease Dissolution Potential In Aquatic Environments For Construction Of Artificial Reefs, Charles Davis Lofton

LSU Doctoral Dissertations

The use of limestone as coastal protection devices and as an oyster cultch material has placed a substantial economic burden on the State of Louisiana. Limestone is not locally available in the State of Louisiana and must be transported from out of state which significantly increases the cost of utilizing the material. Placement of limestone on the unconsolidated soils in coastal Louisiana result in significant losses to sinking of the material due to the density of limestone. Therefore, locally available materials with a lower density compared to limestone are needed to reduce the economic burden of protecting and enhancing coastlines. …

Enhancing The Performance Of Anaerobic Bioreactors For The Biological Degradation Of Volatiles Organic Compounds In Groundwater Using Alternate Electron Acceptors, Leslie Michele Pipkin

LSU Doctoral Dissertations

Engineered anaerobic bioreactors (ABR) constructed from mixed media and sand can biodegrade high concentrations of volatile organic compounds (VOCs). Sustainable treatment of benzene, toluene, ethylbenzene, and xylenes (BTEX), chlorinated ethenes and ethanes were used to investigate the use of engineered ABRs, while also analyzing the system performance of a full-scale ABR system. Experimentations conducted on environmental and biological factors that affect ABR system performance was conducted through serum bottles, columns, and reactor studies.

Column and reactor ABR systems were designed to treat VOCs via biodegradation in groundwater with varying terminal electron acceptors (TEAs). Laboratory-scale column ABRs were constructed to treat …

Diagenesis And Formation Stress In Fracture Conductivity Of Shaly Rocks; Experimental-Modelling Approach In Co2-Rock Interactions, Abiola Olukola Olabode

LSU Doctoral Dissertations

In large scale subsurface injection of carbon dioxide (CO₂) as obtainable in carbon sequestration programs and in environmentally friendly hydraulic fracturing processes (using supercritical CO₂), long term rock-fluid interaction can affect reservoir and seal rocks properties which are essential in monitoring the progress of these operations. The mineralogical components of sedimentary rocks are geochemically active particularly under enormous earth stresses, which generate high pressure and temperature conditions in the subsurface. While geomechanical properties such as rock stiffness, Poisson’s ratio and fracture geometry largely govern fluid flow characteristics in deep fractured formations, the effect of mineralization can …

Rice Hull Bioreactor For Recirculating Aquaculture, Marlon A. Greensword

LSU Doctoral Dissertations

The engineering of floating media biofilters has been optimized over the years. The backwashing process has made them more energy and water efficient. Likewise, moving bed bioreactors (MBBR) are gaining interest and popularity because they are relatively affordable to build. Yet, developing countries’ aquaculture production remains largely excluded from the advances made in recirculating aquaculture systems (RAS). This discrepancy is partially driven by the high costs of media such plastic beads and Kaldnes (KMT) media, commonly used in MBBR.

This dissertation evaluates the usability and profitability of rice hulls (RH), an abundant by-product in many developing nations, as a sinking …

A Decision Making Tool For Incorporating Sustainability Measures In Rigid Pavement Design, Neveen Samy Talaat Soliman

LSU Doctoral Dissertations

One of the most important tools in assessing rigid pavement design sustainability (or environmental impact) is a lifecycle assessment (LCA), which may be applied in any stage of a product’s lifecycle from cradle to grave, such as pavements. Although LCA was the focus of much research and codification by organizations such as the International Organization for Standards and the Society of Environmental Toxicology and Chemistry, limitations exist, such as a) LCA is time consuming; and b) the used data may become outdated, inaccurate, biased, incomplete, and/or expensive to use. These limitations are not a deficiency in LCA as a tool, …

Characterizing The Hydrodynamics Of A Meandering River Neck Cutoff, Christopher Turnipseed

LSU Master's Theses

Meandering river systems often experience a geomorphic phenomenon known as a neck cutoff. The White River of Arkansas has recently undergone several neck cut offs, which have provided a unique opportunity to collect field measurements of the first two years after the opening of the cutoff. In this study the field data was complemented with hydrodynamic simulations to assess the significance of different flow conditions. The findings suggest that flood events play a substantial role in the geomorphic adjustment of the river to the cutoff.

Accumulation And Dynamics Of Petrogenic Pahs On Leaves Of Black Mangrove (Avicennia Germinans), Matthew Decell

LSU Master's Theses

Crude oil from Deepwater Horizon Macondo oil spill is currently present in Louisiana coastal surface sediments and its effects on the coastal ecosystem are still being realized. Deposition of 2- and 3-ring PAHs (alkylated naphthalenes and phenanthrenes) on the exterior of Spartina alterniflora and Avicennia germinans leaves have been demonstrated in marshes impacted by Macondo spill. Whether these deposition events result from contaminated tidal water or volatilization followed by deposition onto the leaf surface has not been conclusively established. Measurements of PAH deposition on the leaf surface of black mangrove (Avicennia germinans) can provide important evidence of the mechanism of …

Unsteady Flow Simulations To Develop Model Scale Discharge Hydrographs For The Expanded Small Scale Physical Model Of The Mississippi River, Ronald Joseph Rodi

LSU Master's Theses

Small-scale HEC-RAS models were used to analyze discharges used to test the Louisiana State University and the Louisiana Coastal Protection & Restoration Authority Expanded Small Scale Physical Model (ESSPM) of the Mississippi River. The HEC-RAS models extend from River Mile 228.4 (Baton Rouge) to the Gulf of Mexico that includes the ESSPM reach which begins at River Mile 173.5 (Donaldsonville). The model scales are 1:6000 horizontally and 1:400 vertically. Using the historic river discharges from 2008 through 2015, the small-scale numerical models proved capable of replicating observed stages along eleven sites of the lower Mississippi River within the targets of …

Method For Quantifying Floating Marsh Strength And Interaction With Hydrodynamics, Jason Haydel Collins Iii

LSU Master's Theses

Louisiana possesses over 350,000 acres of unique floating vegetated systems known as floating marshes or flotants. Due to their buoyant nature, floating marshes are susceptible to high energy changes in the hydrodynamic environment that may result from proposed river diversion projects which introduce flow to areas that are typically somewhat isolated. The overall goal of this research is to improve the understanding of how exposed flotants deteriorate under increased hydrodynamic stresses. More specifically, this thesis aims to answer how the material limits of floating marshes can be measured and how the mats interact with hydrodynamics. The two primary objectives are: …

Transport And Degradation Of Oil Residues On Coastal Beaches, Sirui Wen

LSU Master's Theses

Fourchon Beach, a 9-mile coastal headland located in Louisiana Gulf Coast, has been heavily impacted by the Deepwater Horizon (DWH) oil spill, which began on April 20th 2010. Once on the beach, the oil spill residues were moved, suspended and transported by subsequent washover events. These washover events occur during storm surges, hurricanes or other situations with high water levels; pushing oil residues from the subtidal and intertidal zone of the beach and then depositing them in the supratidal marshes and mudflat areas. In order to determine the impacts of washover events on oil residues, two complementary studies regarding degradation …

Cuticle Accumulation Of Petrogenic Pahs On Spartina Alterniflora: A Novel Exposure Pathway For Marsh Biota, Joyce Gabriel Kassenga

LSU Master's Theses

Louisiana coastal marshes were heavily impacted by the 2010 Deepwater Horizon oil spill. MC252 oil pollution in coastal marshes lead to the exposure of biota to polycyclic aromatic hydrocarbons (PAHs). PAHs are persistent organic pollutants that can reside and accumulate in marsh biota. The aim of this study was to investigate the uptake mechanisms of PAHs by Spartina alterniflora at heavily oiled Bay Jimmy marsh in Barataria Basin, Louisiana. Study objectives were to quantify and investigate the uptake mechanisms of PAHs in the leaves of Spartina. The plant/air partitioning of PAHs was studied using a fugacity approach to determine their …

Analysis Of Cost And Energy Performance Of Geothermal Heat Pump Systems In Southern Louisiana, Claudia De Lourdes Duran Tapia

LSU Master's Theses

In the last three decades of geothermal heat pump (GHP) industry, there has been an urge to present data, especially performance and itemized installation cost, as a plan to reduce the lack of knowledge and trust towards GHP systems for heating and cooling. The potential of GHPs in hot and humid climates is significant [Tao and Zhu, 2012]. However, past research efforts have demonstrated this potential through the use of simulation rather than real-time data. Therefore, the scope of work for this research is to investigate GHP system applications for residential buildings in areas with hot and humid climates. Based …

Impact Of Connected Vehicle Safety Applications On Driving Behavior At Varying Market Penetrations: A Driving Simulator Study, Matthew Alexander Theriot

LSU Master's Theses

The studies conducted in this thesis evaluate the safety benefits of a blind spot warning (BSW) application and a do not pass warning (DNPW) application at low, medium, and high market penetrations (MP) of connected vehicles (CV) using a high-fidelity driving simulator. Using vehicle-to-vehicle (V2V) communication, CVs can exchange information to alert drivers of potential safety hazards and reduce potential crashes during lane change and overtaking maneuvers. A CV testbed was developed to relay visual and auditory warnings when dangerous thresholds were met for each application. For the BSW a proximity-based threshold was used to trigger a warning as a …

Atmospheric Boundary Layer Processes To Mimic Peak Pressures On Low-Rise Buildings: Cfd Versus Full-Scale And Wind Tunnel Measurements, Hamzeh Gol Zaroudi

LSU Doctoral Dissertations

Realistic prediction of peak wind pressures is indispensable in a safe design of low-rise buildings. For several decades wind tunnel testing was employed to obtain wind loads on buildings and other structures. However, there is still doubt in the wind engineering community regarding the adequacy of wind tunnels to predict accurately full-scale pressures on low-rise buildings and small-size structures. The recommendations of the American Society of Civil Engineers (ASCE) 7-10 standard for external pressure coefficients, for roof components and cladding (C&C) design are also based on published wind tunnel data. Recent field measurements show significant deviation of full-scale pressures from …

Modeling Of Size Effects In Metallic Samples Of Confined Volumes, Mohammadreza Yaghoobi

LSU Doctoral Dissertations

In material science, size effects is described as the variation of material properties as the sample size changes. In this dissertation, the size dependency of the material strength is addressed as size effects. The size effects underlying mechanisms depend on the nature of the considered material. In the case of crystalline metals, size effects in crystalline metals are governed by the dislocations, as the primary deformation mechanism, and their interactions with one another and other defects such as grain boundaries. In this dissertation, the size and strain rate effects of fcc metallic samples of confined volumes are investigated during the …

Vibration Control In Wind Turbines For Multi Hazards, Milad Rezaee

LSU Doctoral Dissertations

The increasing demand for reliable and clean energy with a low running cost, has developed wind energy harvesting industry in a fast rate during the past two decades, and has led to wind farms’ spreading in various regions with larger and taller wind turbines. Consequently, it is more likely that wind turbines are installed or planned to be installed in areas with higher possibility of natural multihazard. Therefore, flexible modern wind turbines are subjected to severe dynamic environmental loads. Generated excessive vibrations in the wind turbine’s structure due to these loads can have detrimental effects on energy production, structural lifecycle …