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Development Of Cracking Resistance Prediction Model Of Long-Term Aged Asphalt Mixtures, Peyman Barghabany Mar 2021

Development Of Cracking Resistance Prediction Model Of Long-Term Aged Asphalt Mixtures, Peyman Barghabany

LSU Doctoral Dissertations

With the increasing complexity of asphalt mixture composition, the current volumetric-based Superpave mixture design would not be sufficient to address durability concerns. To address this limitation, performance-based testing is introduced to supplement conventional volumetric mixture design in assessing the cracking resistance of asphalt mixtures. To perform cracking tests, samples need to be aged to represent the most embrittlement case. The current AASHTO standard for asphalt mixture long-term aging (LTA) is a 5-day oven-aging at 85°C. Quality control/assurance practices require samples to be long-term aged prior to a cracking test which is a time-consuming process. Therefore, it would be beneficial to …


Stream Power Analysis Of The Mid-Barataria Conveyance Channel Model, Jack Graham Mar 2021

Stream Power Analysis Of The Mid-Barataria Conveyance Channel Model, Jack Graham

LSU Master's Theses

Louisiana’s coast is disappearing at an alarming rate. Erosion, subsidence, sea level rise, and the devastating impacts from hurricanes have contributed to the loss of thousands of square miles of land that was once a thriving ecosystem. The Louisiana government is taking action to help protect and restore these coastal habitats, which are a home to some two million people and numerous species of animals, birds, and fish. The Mid-Barataria Sediment Diversion is a new type of project to help create land in Barataria Basin. Conceptually, the diversion is designed to use the available sediment and stream power provided by …


Non-Newtonian Model Development For Post-Wildfire Flood Risk Management, Ian Eli Floyd Mar 2021

Non-Newtonian Model Development For Post-Wildfire Flood Risk Management, Ian Eli Floyd

LSU Doctoral Dissertations

Wildfire effected regions of the western U.S. frequently produce non-Newtonian floods (or floods that have a non-linear relationship between stress and deformation) in response to moderate to severe precipitation events. This research presents the development, evaluation, and demonstration of a post-wildfire hydrodynamic one-dimensional and two-dimensional diffusive wave and shallow-water numerical modeling approach that can be used to predict post-wildfire downstream runout of debris flows and floodplain inundation conditions. While researchers have developed a variety of Non-Newtonian approaches to simulate debris flows and mudflows, there has been very limited application to post-wildfire flooding. This can make it difficult to understand the …


Operation Procedures Of Mid-Barataria Sediment Diversion Model To Reproduce Hydraulics And Sediment Transport, Chase Holston Mar 2021

Operation Procedures Of Mid-Barataria Sediment Diversion Model To Reproduce Hydraulics And Sediment Transport, Chase Holston

LSU Master's Theses

The Lower Mississippi River Physical Model (LMRPM) is a distorted, movable bed model that simulates the hydraulics and sediment transport in the lower 195 miles of the Mississippi River. Carved into the model are both existing hydraulic structures, such as the Bonnet Carré Spillway, and proposed structures, such as the Mid-Barataria Sediment Diversion (MBSD). The MBSD will be the first sediment diversion built as part of Louisiana’s Coastal Master Plan, so incorporating the diversion in the LMRPM will be a useful tool to understanding how the diversion can impact the river hydraulics and bedload transport. The objective of this thesis …


Changes In Wetland Soil Processes And Ecosystem Functions Six Years After Marsh Creation In Barataria Bay, Louisiana, Erol R. Knaus Mar 2021

Changes In Wetland Soil Processes And Ecosystem Functions Six Years After Marsh Creation In Barataria Bay, Louisiana, Erol R. Knaus

LSU Master's Theses

Louisiana contains about 40% of the conterminous United States coastal and estuarine wetlands but also has the highest rates of wetland loss at around 80% of the total. Approximately 4,900 km2 of coastal land in Louisiana has been lost since 1930. Our study location, Barataria Bay, has one of the highest coastal wetland erosion rates in the nation, at ∼41 km2 per year; and therefore, is a high priority for wetland restoration activities. In 2014, sandy sediment dredged from the bed of the Mississippi River was placed in Barataria Bay as part of a restoration effort. Samples were …


Temperature Gradient Effects On Behavior And Design Of Prestressed Concrete Girder Bridges, Ahmed Saad Elsayed Mohamed Elshoura Mar 2021

Temperature Gradient Effects On Behavior And Design Of Prestressed Concrete Girder Bridges, Ahmed Saad Elsayed Mohamed Elshoura

LSU Doctoral Dissertations

Temperature variation is an inevitable environmental loading type that affects bridges. Considering temperature effects during structural design is deemed essential for short, medium, and long span bridges. Temperature loading can be categorized into three components; uniform temperature, vertical temperature gradient, and transverse temperature gradient. Temperature variation causes additional movements, stresses, and internal forces that should be considered in the design of bridges. In this study, the temperature effects of vertical and transverse temperature gradients are investigated for continuous prestressed concrete bridges.

Thermal restraint moments induced by vertical temperature gradients on prestrssed concrete bridges are investigated by performing three-dimensional (3D) finite …


Resource And Energy Recovery From Wastewater Using Advanced Bioelectrochemical Systems, Sidan Lu Mar 2021

Resource And Energy Recovery From Wastewater Using Advanced Bioelectrochemical Systems, Sidan Lu

LSU Doctoral Dissertations

Water pollution and energy depletion are two critical issues in the world that limit the sustainable development of human society. In this study, several advanced (photo) bioelectrochemical systems (BESs) were proposed for effective energy (electricity and H2) and nutrients (N and P) recovery from wastewater, solar energy, seawater, and river water. The first study demonstrated high effectiveness of a novel resource-recovery microbial fuel cell (RRMFC) for wastewater treatment and nutrient recovery from synthetic urine-containing wastewater. Over one cycle (∼3 days), 99% of urea, 97% of COD, 99% of histidine, 91% of creatinine, 99% of sodium acetate, 98% of …


Educational Theory-Embedded Training For Construction Industry Professionals, Hazem Jadallah Mar 2021

Educational Theory-Embedded Training For Construction Industry Professionals, Hazem Jadallah

LSU Doctoral Dissertations

Workforce training is needed throughout the construction industry to create and maintain competent workers; unfortunately, most construction training and education research focuses on university student education. The focus of this dissertation research is the current state of educational-theory embedded construction workforce training, how such trainings are effective, and how they may be further optimized based on established educational theory. This is accomplished through a review of construction training for current industry professionals, an evaluation of the assessment criteria used to measure effectiveness, followed by the creation of a framework for construction training.

There is a lack of recommendations for improvement …


Quality Assessment Of Flexible Pavement Automated Cracking Data In Louisiana, Mostafiz Emtiaz Jan 2021

Quality Assessment Of Flexible Pavement Automated Cracking Data In Louisiana, Mostafiz Emtiaz

LSU Master's Theses

Pavement distress survey is the most critical and integral part of pavement management system. Transportation agencies all over the world depends on the accurate pavement distress survey to take major decisions like pavement rehabilitation or reconstruction. Pavement management at the network level requires accurate pavement distress survey to decide the allocation of budget for pavement maintenance, rehabilitation and reconstruction. This study started collected network-level cracking distress data through manual measurements on high-resolution pavement images and the results were used as the ground truth measurements to evaluate the corresponding automated distress data from the Pavement Management System database. Results showed that …


Effectiveness Of Mechanical Test In Ascertaining Moisture Damage Of Asphalt Mixtures., Sanchit Sachdeva Nov 2020

Effectiveness Of Mechanical Test In Ascertaining Moisture Damage Of Asphalt Mixtures., Sanchit Sachdeva

LSU Master's Theses

Infiltrated moisture combined with repeated action of traffic and environmental loading generates distresses which adversely affect the durability of asphalt pavements. Almost 94% of states' highway agencies use either the Loaded Wheel Tracking (LWT) test or the Modified Lottman test to capture asphalt mixtures' moisture susceptibility. However, the current LWT and the modified Lottman test practice lack accuracy in relating laboratory performance to observed field performance.

The study's primary objective was to evaluate the capability of different laboratory mechanical test methods to predict moisture susceptibility of asphalt mixtures. Asphalt binder and mixture experiments were conducted to achieve the objective of …


Modeling Distributed Source Control Infrastructure At Neighborhood Scale For Mitigating Flood Risk In Amite River Watershed, Ahmad Amin Shefai Nov 2020

Modeling Distributed Source Control Infrastructure At Neighborhood Scale For Mitigating Flood Risk In Amite River Watershed, Ahmad Amin Shefai

LSU Master's Theses

Flooding has always been a major threat to mankind. This is particularly true in urban areas due to urbanization-induced increasing impervious areas and subsequent increasing urban surface runoff, causing an increasing flooding risk to urban areas in spite of the fact that extensive flood control infrastructure has been constructed. The overall goal of this thesis is to present a distributed source control infrastructure-based approach for mitigating the flood risk. The new flood mitigation approach is demonstrated through the model implementation of a series of distributed source control infrastructure systems in the city of Denham Springs at a neighborhood scale. The …


An Approach To Counting Vehicles From Pre-Recorded Video Using Computer Algorithms, Mishuk Majumder Nov 2020

An Approach To Counting Vehicles From Pre-Recorded Video Using Computer Algorithms, Mishuk Majumder

LSU Master's Theses

One of the fundamental sources of data for traffic analysis is vehicle counts, which can be conducted either by the traditional manual method or by automated means. Different agencies have guidelines for manual counting, but they are typically prepared for particular conditions. In the case of automated counting, different methods have been applied, but You Only Look Once (YOLO), a recently developed object detection model, presents new potential in automated vehicle counting. The first objective of this study was to formulate general guidelines for manual counting based on experience gained in the field. Another goal of this study was to …


Engineering Characteristics Of Nest Building Geomaterials Used By Mud Dauber Species, Noura Saleh Nov 2020

Engineering Characteristics Of Nest Building Geomaterials Used By Mud Dauber Species, Noura Saleh

LSU Master's Theses

Mud dauber wasps construct their nests using soil from adjacent areas. Mud dauber nests have been studied from an entomological perspective. However; the properties of the nest material remain unexplored from a soil engineering perspective. This study investigated the physical and mechanical properties of the nest soil for use in future bio-inspired design to improve soil behavior as a construction material. To achieve this goal, nests from three mud dauber species (black and yellow, organ pipe, and steel blue) were collected from locations near Baton Rouge, Louisiana. The shape, weight, moisture content, organic content, and specific gravity of the nests …


Water-Energy Nexus: Studies On Salinity Gradient Energy Harvest And Desalination, Guangcai Tan Nov 2020

Water-Energy Nexus: Studies On Salinity Gradient Energy Harvest And Desalination, Guangcai Tan

LSU Doctoral Dissertations

Water and energy are fundamentally linked, and both are important for the development of human society. The demand for renewable energy and freshwater are two global challenges in the 21st century. Herein, a novel chloride-ion (Cl) concentration flow cell (CFC) based on two symmetrical electrodes (BiCl3, CoCl2, VCl3, or BiOCl) separately by a cation-exchange membrane was used as an efficient method to recover salinity gradient (SG) energy. The CFC with metal chloride electrodes (BiCl3, CoCl2, and VCl3) was based on Cl extraction/insertion, and that …


P-Cresol Biogenesis During Bioremediation Aimed At Stimulating Chlorinated Solvent Dehalogenation, Alexis Gathings Nov 2020

P-Cresol Biogenesis During Bioremediation Aimed At Stimulating Chlorinated Solvent Dehalogenation, Alexis Gathings

LSU Master's Theses

The broad goal of the research described in this thesis was to better understand the potential for biologically mediated production of p-cresol in groundwater at a Superfund site located in south Louisiana. Previous literature reports that microorganisms known to carry out the transformation from L-tyrosine to p-cresol occur in diverse environments.

In the research described in this thesis, studies were conducted utilizing groundwater from the Superfund site during the course of enhanced in situ bioremediation practices aimed at stimulating reductive dehalogenation of chlorinated solvent contamination. Microbial communities established with groundwater sampled from the Superfund site were observed to …


A Modelling Study For Smart Pigging Technique For Pipeline Leak Detection, Caitlyn Judith Thiberville Nov 2020

A Modelling Study For Smart Pigging Technique For Pipeline Leak Detection, Caitlyn Judith Thiberville

LSU Master's Theses

Although leak incidents continue, a pipeline remains the most reliable mode of transportation within the oil and gas industry. It becomes even more important today because the projection for new pipelines is expected to increase by 1 billion BOE through 2035. In addition, increasing number and length of subsea tiebacks face new challenges in term of data acquisition, monitoring, analysis, and remedial actions. Passive leak-detection methods commonly used in the industry have been successful with some limitations in that they often cannot detect small leaks and seeps. In addition to a thorough review of related topics, this study investigates how …


Bridge Design Replacement Project For The Charenton Canal Bridge On La 87 And Comparison Of Deck Design Methods, Emily Rone Nov 2020

Bridge Design Replacement Project For The Charenton Canal Bridge On La 87 And Comparison Of Deck Design Methods, Emily Rone

Honors Theses

No abstract provided.


A Framework For Augmenting Building Performance Models Using Machine Learning And Immersive Virtual Environment, Chanachok Chokwitthaya Oct 2020

A Framework For Augmenting Building Performance Models Using Machine Learning And Immersive Virtual Environment, Chanachok Chokwitthaya

LSU Doctoral Dissertations

Building performance models (BPMs), such as building energy simulation models, have been widely used in building design. Existing BPMs are mainly derived using data from existing buildings. They may not be able to effectively address human-building interactions and lack the capability to address specific contextual factors in buildings under design. The lack of such capability often contributes to the existence of building performance discrepancies, i.e., differences between predicted performance during design and the actual performance.

To improve the prediction accuracy of existing BPMs, a computational framework is developed in this dissertation. It combines an existing BPM with context-aware design-specific …


Developing A Competency Model For Highway Safety Engineers: A Delphi Method, Garrett K. Wheat Oct 2020

Developing A Competency Model For Highway Safety Engineers: A Delphi Method, Garrett K. Wheat

LSU Doctoral Dissertations

The primary purpose of this study was to determine the core competencies needed by State DOT Highway Safety Engineers as perceived by Highway Safety experts in the United States. First, a list of competencies was identified. Next, a panel of Highway Safety experts determined the importance of each identified competency for the current year (2020) and for the future (year 2030). Finally, ratings provided by the panel were tested for the presence of consensus.

For this study, the researcher used a Delphi Method as classified by Delbecq, Van de Ven, and Gaustafson (1975). Through this method, a panel of forward-thinking …


Using Spatial Analysis And Machine Learning Techniques To Develop A Comprehensive Highway-Rail Grade Crossing Consolidation Model, Samira Soleimani Oct 2020

Using Spatial Analysis And Machine Learning Techniques To Develop A Comprehensive Highway-Rail Grade Crossing Consolidation Model, Samira Soleimani

LSU Doctoral Dissertations

The safety of highway-railroad grade crossings (HRGC) is still an issue in the United States of America (USA). The grade crossing is where a railroad crosses a road at the same level without any over or underpass. To improve the safety of crossings, the crossings’ condition should be explored from several aspects such as engineering design (speed limit, warning signs, etc.), road condition (number of lanes, surface markings, etc.), rail design (the type of track, ballast, etc.), temporal variables (weather, visibility, time of day, lightning, etc.), social variables (population, race, etc.), and last but not least, spatial variables (the type …


Historical Changes In Planform Geometry Of The Amite And Comite Rivers And Implications On Flood Routing, Kathleen E. Harris Sep 2020

Historical Changes In Planform Geometry Of The Amite And Comite Rivers And Implications On Flood Routing, Kathleen E. Harris

LSU Master's Theses

The Amite River Basin is a 2,220 square-mile basin spanning from southwest Mississippi through southeast Louisiana, encompassing Baton Rouge and its suburbs. In response to historic flooding in August 2016 and other major flood events in the past several decades, the basin has been the subject of a number of studies to quantify the impacts of changes in land-use and reduction in river length and sinuosity. However, there have yet to be relationships defined between the changes in the historical river planform and the resulting flow, stages, and subsequent flood depths. River lengths and sinuosity were measured from the 1930s …


Numerical Modeling Of Wave- And Current-Supported Turbidity Currents Over Erodible Bed, Sahar Haddadian Aug 2020

Numerical Modeling Of Wave- And Current-Supported Turbidity Currents Over Erodible Bed, Sahar Haddadian

LSU Doctoral Dissertations

The physical processes that route sediments from nearshore to the continental margin provide vital information to the global assessment of the geochemically important matter and the life in the ocean. Therefore, understanding these processes at the fundamental level will help develop accurate models that can be integrated into operational ocean models. Wave- and current-supported turbidity currents (WCSTCs) are one of the mechanisms that deliver sediments to the continental margin. WCSTCs are slow-moving turbidity currents where near-bed turbulence driven by strong surface waves and/or currents, tide- and/or wind-driven, maintain the turbidity current in motion. This study investigates the along-shelf current-supported turbidity …


Development Of Artificial Intelligence Approach To Nowcasting And Forecasting Vibrio Prevalence In Coastal Waters, Peyman Hosseinzadeh Namadi Aug 2020

Development Of Artificial Intelligence Approach To Nowcasting And Forecasting Vibrio Prevalence In Coastal Waters, Peyman Hosseinzadeh Namadi

LSU Doctoral Dissertations

Vibrio parahaemolyticus (V.p) is an epidemiologically significant pathogen that poses high risks to the human health and shellfish industry, calling for predictive models for management interventions. This study presents an Artificial Intelligence(AI)-based approach to predicting and reducing the risks. The AI-based approach involves the identification of environmental indicators and their optimum variation ranges favoring V.p prevalence, the development of nowcasting and forecasting models for predicting V.p prevalence, and the creation of remote sensing algorithms for mapping concentrations of V.p and its environmental indicators by synergistically combining the Deep Neural Network (DNN) modeling technique, Genetic Programming (GP) method, R …


Isolation And Characterization Of Bacteria In A Toluene-Producing Enrichment Culture Derived From Contaminated Groundwater At A Louisiana Superfund Site, Madison Mikes Aug 2020

Isolation And Characterization Of Bacteria In A Toluene-Producing Enrichment Culture Derived From Contaminated Groundwater At A Louisiana Superfund Site, Madison Mikes

LSU Master's Theses

In an effort to better understand the role that various microbes may play in toluene production, bacteria from a toluene-producing enrichment culture derived from contaminated groundwater at a Superfund site were cultivated and isolated on low nutrient solid media. A total of 14 solid medium formulations containing varying pH ranges, carbon sources, solidifying agents, and incubation gas headspaces were used to obtain 278 isolates in pure culture. Isolated bacteria, identified using partial 16S rRNA gene sequences, were most closely related with the genera Anoxybacillus, Azospira, Bacillus, Bradyrhizobium, Cellulosimicrobium, Micrococcus, and Propionicimonas.

Further attempts …


Hydraulic Effects Of The Lower Mississippi River Batture, David P. May Jul 2020

Hydraulic Effects Of The Lower Mississippi River Batture, David P. May

LSU Master's Theses

The Lower Mississippi River (LMR), since the creation of the Mississippi River and Tributaries (MR&T) project, has been extensively modified to support navigation and flood risk reduction. The components of the MR&T system, implemented to support the above missions, have performed successfully for many decades, but not without contention. Rising stages in recent years have led to the questioning of the hydraulic impact of navigation dikes and river training methodologies. Multiple studies have been performed (Biedenharn, 2000, May 2017, Mayne, 2018, and Simon, 2019) that indicate these river training structures have minimal impact to stage during flood conditions. It has …


Laboratory And Short-Term Field Performance Of Crumb Rubber Modified Asphalt Emulsion In Chip Seal Applications, Md Nafiur Rahman Jul 2020

Laboratory And Short-Term Field Performance Of Crumb Rubber Modified Asphalt Emulsion In Chip Seal Applications, Md Nafiur Rahman

LSU Master's Theses

Chip sealing is a commonly used pavement maintenance treatment that aims to delay pavement deterioration by reducing water infiltration and restoring skid resistance. Loss of aggregate and bleeding are considered the major failure mechanisms in chip seal, and therefore, are the main design criteria for this treatment method. The objective of this study was to evaluate the laboratory and short-term field performance of chip seals prepared with different types of asphalt emulsions, application rates, and aggregate blends. A newly introduced crumb-rubber modified asphalt emulsion was evaluated that allows chip seal installation at the same temperature of a standard emulsion. Types …


Data-Driven And Model-Based Methods With Physics-Guided Machine Learning For Damage Identification, Zhiming Zhang Jun 2020

Data-Driven And Model-Based Methods With Physics-Guided Machine Learning For Damage Identification, Zhiming Zhang

LSU Doctoral Dissertations

Structural health monitoring (SHM) has been widely used for structural damage diagnosis and prognosis of a wide range of civil, mechanical, and aerospace structures. SHM methods are generally divided into two categories: (1) model-based methods; (2) data-driven methods. Compared with data-driven SHM, model-based methods provide an updated physics-based numerical model that can be used for damage prognosis when long-term data is available. However, the performance of model-based methods is susceptible to modeling error in establishing the numerical model, which is usually unavoidable due to model simplification and omission. The major challenge of data-driven SHM methods lies in data insufficiency, e.g., …


Reliability Analysis Of Concrete Gravity Dams Under Earthquake Loads, Anu Abraham May 2020

Reliability Analysis Of Concrete Gravity Dams Under Earthquake Loads, Anu Abraham

LSU Master's Theses

Dams are infrastructure assets of extreme importance; the failure of which can have catastrophic consequences on adjacent communities. Therefore, it is prudent for authorities to evaluate the safety of existing dams in seismically active regions. This thesis focuses on carrying out a reliability analysis of concrete gravity dams under earthquake loads using an enhanced finite element model. For many years, reliability studies on concrete gravity dams were performed using a finite element model that considered a massless foundation and assumed that water is incompressible. Moreover, the design ground motion was applied without any modification either at the bottom fixed boundary …


Study Of The Effect Of Heating - Cooling Cycles On The Clay - Concrete Pile Interface Characteristics, Abedalqader Ahmad Idries May 2020

Study Of The Effect Of Heating - Cooling Cycles On The Clay - Concrete Pile Interface Characteristics, Abedalqader Ahmad Idries

LSU Master's Theses

This study aimed at investigating the effect of heating-cooling cycles on the interface strength parameters of clay soil-concrete for potential applications to improve the side capacity of piles driven in clayey soil by the heating process, and also to assess the behavior of geothermal piles regarding interface shear strength parameters. A modified large-size direct shear test device with the dimensions 12” x 12” x 8”, was used in this study. A concrete block (12” x 12” x 4”) of similar texture and smoothness to the concrete piles was used to simulate the pile interface. The tested clays are low plasticity …


Identification Of Top-Down, Bottom-Up, And Cement-Treated Reflective Cracks Using Convolutional Neural Network And Artificial Neural Network, Nirmal Dhakal May 2020

Identification Of Top-Down, Bottom-Up, And Cement-Treated Reflective Cracks Using Convolutional Neural Network And Artificial Neural Network, Nirmal Dhakal

LSU Doctoral Dissertations

The objective of this study was to formulate a Convolutional Neural Networks (CNN) model and to develop a decision-making tool using Artificial Neural Networks (ANN) to identify top-down, bottom-up, and cement treated (CT) reflective cracking in in-service flexible pavements. The CNN’s architecture consisted of five convolutional layers with three max-pooling layers and three fully connected layers. Input variables for the ANN model were pavement age, asphalt concrete (AC) thickness, annual average daily traffic (AADT), type of base, crack orientation, and crack location. The ANN network architecture consisted of an input layer of six neurons, a hidden layer of ten neurons, …