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Full-Text Articles in Engineering

Concentrations, Sources, And Health Risks Of Particulate Matter In Southeast Us.: Current Status And Future Changes, Fenglin Han Dec 2019

Concentrations, Sources, And Health Risks Of Particulate Matter In Southeast Us.: Current Status And Future Changes, Fenglin Han

LSU Doctoral Dissertations

Evaluation of long-term air quality trends and prediction of future air quality may help to design and demonstrate effectiveness of control strategies and guide future air quality management. As one of the six criteria air pollutants (CAPs) regulated by the US Environmental Protection Agency (EPA), particulate matter with aerodynamic diameter of 2.5 µm or less (PM2.5) is of great interests since it has adverse effects on human health, visibility and climate. This study aims to understand the current status and future changes in concentrations, sources, and health risks of PM2.5 in Southeast US. Firstly, observations were analyzed …


Safety Assessment Of Road Vehicle In Crosswind Considering Driver Behavior, Jiexuan Hu Nov 2019

Safety Assessment Of Road Vehicle In Crosswind Considering Driver Behavior, Jiexuan Hu

LSU Doctoral Dissertations

With expansion of the economy, more and more highway networks extend to coastal areas and mountain valley areas. Vehicles will be exposed to strong crosswinds when driven on these highway roads, especially in hurricane season and in winter in these two different topographic areas. Strong crosswinds threaten the safety of transportation infrastructure and passing vehicles in forms of vehicle accidents that usually result in traffic blockage and driver injury, posing negative effects on economic growth. This dissertation aimed to evaluate the vehicle safety when running through crosswinds in consideration of driver behaviors.

Firstly, the aerodynamic characteristics of road vehicles were …


Evaluation Of The Rheological Behaviors And Molecular Composition Properties Of Crumb Rubber Modified Emulsion For Chip Seal, Md Tanvir Ahmed Sarkar Nov 2019

Evaluation Of The Rheological Behaviors And Molecular Composition Properties Of Crumb Rubber Modified Emulsion For Chip Seal, Md Tanvir Ahmed Sarkar

LSU Master's Theses

An experimental study was conducted to characterize the chemical, molecular, and rheological properties of different asphalt emulsions including a newly introduced tire rubber modified asphalt emulsion. One tire rubber modified asphalt emulsion (CRS-2TR), two conventional emulsions (CRS-2 and CRS-2P), and one asphalt rubber binder (AC20-5TR) were evaluated. The differences in functional groups, chemical composition, and molecular weight distribution of the asphalt binder and emulsions under different aging conditions (Original, RTFO-aged, and PAV-aged) were evaluated by the Saturates, Aromatics, Resins and Asphaltenes (SARA) fractionation test, High-Pressure Gel Permeation Chromatography (HP-GPC), and Fourier Transform Infrared Spectroscopy (FTIR) test, respectively. Superpave Performance Grade …


Exploring Occupant Behavioral Intentions In Immersive Virtual Environment To Enhance The Design And Engineering Of Sustainable Buildings, Sanaz Saeidi Oct 2019

Exploring Occupant Behavioral Intentions In Immersive Virtual Environment To Enhance The Design And Engineering Of Sustainable Buildings, Sanaz Saeidi

LSU Doctoral Dissertations

Accurately simulating occupant behavior is essential to improve our understanding about the future energy performance of the buildings. To date, most of the information related to the occupancy behaviors has been gathered through field observations and/or performing experiments within the lab environments. Even though these common data collection methods are effective and reliable for the existing buildings, using such data to project occupant behaviors in other contexts is likely to lead to uncertainties. The most significant theoretical achievement of this dissertation was to provide the future building occupants with thermal experience of non-physically existent environments. In this dissertation occupant behavior …


Investigation Of Subsurface Stratigraphy And Groundwater Dynamics In The Mississippi River Delta, An Li Oct 2019

Investigation Of Subsurface Stratigraphy And Groundwater Dynamics In The Mississippi River Delta, An Li

LSU Doctoral Dissertations

The Mississippi River Delta (MRD) is socioeconomically important to the state of Louisiana and the United States. Various types of land-water system data have been collected in the MRD. However, very few efforts have been made to utilize these datasets in modeling regional stratigraphy and groundwater dynamics in the MRD, especially for the upper 50 m of the depth. In this interval of depth, the Mississippi River and surrounding interdistributary bays intensively interact with the groundwater system. The lack of knowledge in regional stratigraphy and groundwater dynamics hinder an understanding of how hydrogeological setting affects processes such as surface-groundwater interaction, …


Effect Of Light Activated Self-Healing Polymers On The Performance Of Asphalt Pavement Containing Recycled Asphalt Materials (Rap/Ras), Sharareh Shirzad Oct 2019

Effect Of Light Activated Self-Healing Polymers On The Performance Of Asphalt Pavement Containing Recycled Asphalt Materials (Rap/Ras), Sharareh Shirzad

LSU Doctoral Dissertations

A new generation of Ultraviolet (UV) light-induced self-healing polymers was introduced for the asphalt pavement application with the aim to enhance pavements durability while increasing its service life. The developed self-healing polymer was mixed with asphalt binder using two different methods, passive and reactive. For the passive method, the cured self-healing polymer was ground to smaller particle size and then it was mixed with asphalt binder using a high shear stirrer and at a high temperature. For the reactive method, self-healing polyurethane pre-polymer was added to the asphalt binder at a lower temperature and lower shear rate compare to the …


Groundwater Management Optimization And Saltwater Intrusion Mitigation Under Uncertainty, Jina Yin Sep 2019

Groundwater Management Optimization And Saltwater Intrusion Mitigation Under Uncertainty, Jina Yin

LSU Doctoral Dissertations

Groundwater is valuable to supply fresh water to the public, industries, agriculture, etc. However, excessive pumping has caused groundwater storage degradation, water quality deterioration and saltwater intrusion problems. Reliable groundwater flow and solute transport modeling is needed for sustainable groundwater management and aquifer remediation design. However, challenges exist because of highly complex subsurface environments, computationally intensive groundwater models as well as inevitable uncertainties. The first research goal is to explore conjunctive use of feasible hydraulic control approaches for groundwater management and aquifer remediation. Water budget analysis is conducted to understand how groundwater withdrawals affect water levels. A mixed integer multi-objective …


Visualizing The Fate And Distribution Of Pahs In Spartina And Avicennia Tissues From Barataria Basin, La, Kristina Jeannette Sebastian Aug 2019

Visualizing The Fate And Distribution Of Pahs In Spartina And Avicennia Tissues From Barataria Basin, La, Kristina Jeannette Sebastian

LSU Master's Theses

During crude oil spill events, vegetation in marsh environments sequester polycyclic aromatic hydrocarbons (PAHs) from the crude oil by partitioning from the air phase through the waxy cuticle on the leaf surface. Recent studies from Macondo oil-impacted marshes have demonstrated that cycling of low molecular weight petrogenic PAHs occurs through the cuticle and other leaf tissue. At present, our understanding of how PAHs travel through the cuticle is coarse and limited by grab samples across the entire leaf, which preventing a full understanding the dynamics of PAH cycling in this environment. Multiphoton (MP) confocal microscopy visualizes the distribution of PAHs …


Performance Study Of Link Slab Continuity In Prestressed Concrete Bridges, Marco Tulio Canales Jr Aug 2019

Performance Study Of Link Slab Continuity In Prestressed Concrete Bridges, Marco Tulio Canales Jr

LSU Doctoral Dissertations

Link slabs in bridges can be a cost-effective solution to increase the service life of bridge structures. The partial continuity condition in link slab bridges, however can be challenging to quantify. In this work link slab performance is studied by means of a parametric study, a long-term Structural Health Monitoring (SHM) System, and a detailed finite-element model.

The parametric study was conducted using mathematical and a two-dimensional (2D) finite element model. The study considers bridge design factors such as number of spans, span length, span length ratio, girder separation, and temperature settings, in conjunction with the corresponding girder and support …


Sodium-Ion Concentration Flow Cell Stacks For Salinity Gradient Energy Recovery: Power Generation Of Series And Parallel Configurations, Elizabeth Whiddon Jul 2019

Sodium-Ion Concentration Flow Cell Stacks For Salinity Gradient Energy Recovery: Power Generation Of Series And Parallel Configurations, Elizabeth Whiddon

LSU Master's Theses

Salinity gradient (SG) energy is a renewable and clean energy resource that exists worldwide from the change in Gibbs free energy when two solutions with different salinities are mixed. More recently, concentration flow cells (CFCs) have been introduced as a new technology for SG energy recovery with the highest reported power density output to date, as a result of the utilization of both the electrode potential and Donnan potential. In this study, multiple CFCs were connected to form a consecutive number of stacks, and systematic analysis was conducted to investigate the influence of both parallel and series electrical wire connections …


Reliability Of Corroding Reinforced Concrete Structures, Travis Honore Jul 2019

Reliability Of Corroding Reinforced Concrete Structures, Travis Honore

LSU Master's Theses

The enhanced performance due to the addition of steel within concrete elements has thrust reinforced concrete structures to be one of the most commonly used construction materials in the world. Reinforced concrete structures are exposed to a variety of deterioration mechanisms during their operational existence, each of which contributes to reducing their service life, durability, and load bearing capacity. The longevity of these reinforced concrete structures is strongly connected to degradation processes, whose origin is environmental and/or functional. Among these processes is the initiation and evolution of corrosion on the steel reinforcement. Steel reinforcement has direct effects on the durability, …


Field Performance And Cost Effectiveness Of Crack Sealing In Flexible And Composite Pavements, Momen Ragab Mousa Jun 2019

Field Performance And Cost Effectiveness Of Crack Sealing In Flexible And Composite Pavements, Momen Ragab Mousa

LSU Doctoral Dissertations

Surface cracking is one of the major surface distresses in asphalt concrete (AC) pavement, allowing water infiltration through the cracks, causing stripping in asphalt pavement layers, and weakening and deteriorating the base and/or subgrade. Its treatment, therefore, is one of the major activities in pavement preservation for many state DOTs. Among the various treatment methods currently available to preserve AC pavement with existing surface cracking are various forms of crack sealing. Crack sealing is not a common practice to Louisiana highways since the benefit of such treatment appears to be affected by the elevation of the ground water table. Studies …


Evaluation Of Traffic Speed Deflectometer For Pavement Structural Evaluation In Louisiana, Zia Uddin Ahmed Zihan Jun 2019

Evaluation Of Traffic Speed Deflectometer For Pavement Structural Evaluation In Louisiana, Zia Uddin Ahmed Zihan

LSU Master's Theses

Many state agencies have recognized the importance of incorporating pavement structural conditions in the selection of maintenance and rehabilitation (M&R) strategies along with functional indices. To measure in-service pavement structural capacity, surface deflection under a defined load has been typically used. The Rolling Wheel Deflectometer (RWD) and Traffic Speed Deflectometer (TSD) have emerged as continuous pavement deflection-measuring devices as they operate at traffic speed and reduces lane closure and user delays.

The research objective of this study was to assess the feasibility of using TSD measurements at the network-level for pavement conditions structural evaluation in Louisiana. To achieve the objectives …


Qualitative And Quantitative Flow Visualization Studies On A Distorted Hydraulic Physical Model, Patrick Scott Jun 2019

Qualitative And Quantitative Flow Visualization Studies On A Distorted Hydraulic Physical Model, Patrick Scott

LSU Master's Theses

The submergence of coastal wetlands in south Louisiana leaves communities, commerce, industry, and ecosystems vulnerable to extreme weather events and human and natural disasters. The state of Louisiana has developed a plan to mitigate coastal land loss and with the help of Louisiana State University and the Lower Mississippi River Physical Model, projects like large scale sediment diversions will be extensively tested and researched to ensure proper implementation and operation. Due to scaling and distortion of the physical model, complete similitude with its prototype is not expected and scale effects are anticipated to affect the hydrodynamics and, as a result, …


Atmospheric Deposition Of Nitrogen And Sulfur In China: Current Status And Future Changes, Cheng Shi Jun 2019

Atmospheric Deposition Of Nitrogen And Sulfur In China: Current Status And Future Changes, Cheng Shi

LSU Master's Theses

Dry and wet deposition of nitrogen (N) and sulfur (S) has detrimental impacts on the health of both human and ecosystems. Intensive human activities are responsible for elevating emissions and deposition of N and S species. Large population and fast industrial development led China to one of the countries with highest acid deposition. The large fluxes of N and S deposition have caused acidification of surface water and soil, which damages plant growth and biodiversity in China. N and S deposition has been investigated using ground-based monitoring networks and satellite-based sensors. The limitation of location of monitoring sites and performance …


Living Shorelines As Alternative Methods Of Shoreline Protection, Hunter Shows Jun 2019

Living Shorelines As Alternative Methods Of Shoreline Protection, Hunter Shows

LSU Master's Theses

Louisiana’s marshes and coastal estuaries are losing habitat at an alarming rate. High rates of sea level rise coupled with coastal subsidence are turning once thriving marsh land into open water. The sediment starved Mississippi River Delta is drowning, making families homes, property, and livelihoods increasingly vulnerable every year. Significant funding is being allocated for projects to offset the increasing erosion including but not limited to diversions, marsh creation, ridge restoration, and shoreline protection projects.

Living shorelines, for the sake of this study, can be defined as a form of shoreline protection which helps shoreline stabilization and erosion reduction while …


A Decision-Making Tool For Incorporating Cradle-To-Gate Sustainability Into Pavement Design, Sujata Subedi Jun 2019

A Decision-Making Tool For Incorporating Cradle-To-Gate Sustainability Into Pavement Design, Sujata Subedi

LSU Master's Theses

The need to continually maintain an aged and crumbling national roadway network, together with a growing demand for upgrading has resulted in major environmental and economic impacts around the nation. This has led to an interest in developing a structured framework to quantify the sustainability performance of pavements by balancing economic and environmental performance against engineering criteria. This study developed an Environment Product Declaration (EPD) based, decision-making framework to quantify the sustainability of pavement design alternatives. In this study, the sustainability of pavement is described in tandem with Environmental and Economic performance criteria. First, the Environmental analysis was inclusive of …


Numerical Modeling Of Wave Dynamics And Sediment Transport Near The Mississippi Birdfoot Delta And Barataria Estuary, Soroush Sorourian May 2019

Numerical Modeling Of Wave Dynamics And Sediment Transport Near The Mississippi Birdfoot Delta And Barataria Estuary, Soroush Sorourian

LSU Doctoral Dissertations

The Barataria Basin is a large estuarine system in Southeastern Louisiana, connected to the Gulf of Mexico through a number of inlets, the most important of which is the Barataria Pass. This research examines, during April-June 2010 including both cold front passage and calm summer-time wind regimes, the wave dynamics in this basin and in its major inlets, morphological evolution near the Barataria Pass, and the budgeting and dispersal of the Mississippi River sediment in the birdfoot delta region. An unstructured grid, terrain following, high resolution coupled FVCOM-SWAVE-SED model is employed and validated in this study. The numerical model results …


Analytical And Numerical Modeling Of Cavity Expansion In Anisotropic Poroelastoplastic Soil, Kai Liu May 2019

Analytical And Numerical Modeling Of Cavity Expansion In Anisotropic Poroelastoplastic Soil, Kai Liu

LSU Doctoral Dissertations

Cavity expansion/contraction problems have attracted intensive attentions over the past several decades due to its versatile applications, such as the interpretation of pressuremeter/piezocone penetration testing results and the modelling of pile installation/tunnel excavation in civil engineering, and the prediction of critical mud pressure required to maintain the wellbore stability in petroleum engineering. Despite the fact that various types of constitutive models have been covered in the literature on this subject, the soils and/or rocks were usually treated as isotropic geomaterials.

In recognition of the above fact, this research makes a substantial extension of the fundamental cavity expansion theory by considering …


Identification And Reduction Of Uncertainties In Watershed-Scale Flow And Water Quality Modeling, Maryam Roostaee Apr 2019

Identification And Reduction Of Uncertainties In Watershed-Scale Flow And Water Quality Modeling, Maryam Roostaee

LSU Doctoral Dissertations

This study identified important uncertainties affecting watershed-scale flow and water quality simulations and recommended modeling options for reducing the uncertainties by means of the Hydrological Simulation Program-FORTRAN (HSPF) model. Specifically, parameter-induced uncertainties in HSPF model were estimated along with uncertainties associated with DEM resolutions and sources. National Elevation Dataset (NED) DEMs with original and resampled resolutions of 3.5, 10, 30 and 100m were utilized for manual and automatic delineation of three watersheds with different gradients in HSPF model to identify the effects of DEM resolution, DEM resampling, delineation method and watershed gradient on the simulation of streamflow, nitrate (NO3 …


Examining The Effect Of Multiple Route Choice Criteria On Hurricane Evacuation Traffic Through External Validation Of Simulations, Haggai D. Davis Iii Apr 2019

Examining The Effect Of Multiple Route Choice Criteria On Hurricane Evacuation Traffic Through External Validation Of Simulations, Haggai D. Davis Iii

LSU Master's Theses

Hurricane evacuations can be a chaotic experience for individuals involved, but researchers have attempted to find patterns in the routes people take. One paper laid out a model for predicting route choice based upon features that are different than standard route choice influencers. This thesis attempted to evaluate the accuracy of that model by using TransModeler modeling software. Using the building blocks of the HEMP project, this project compared the new model to the standard model and evaluated the two based upon the ability to reproduce real-world results. Interestingly, the two did not come out significantly different possibly because the …


Assessment And Correction Of Lidar-Derived Dems In The Coastal Marshes Of Louisiana, William M. Lauve Mar 2019

Assessment And Correction Of Lidar-Derived Dems In The Coastal Marshes Of Louisiana, William M. Lauve

LSU Master's Theses

The onset of airborne light detection and ranging (lidar) has resulted in expansive, precise digital elevation models (DEMs). DEMs are essential for modeling complex systems, such as the coastal land margin of Louisiana. They are used for many applications (e.g. tide, storm surge, and ecological modeling) and by diverse groups (e.g. state and federal agencies, NGOs, and academia). However, in a marsh environment, it is difficult for airborne lidar to produce accurate bare-earth measurements and even accurate elevations are rarely verified by ground truth data. The accuracy of lidar in marshes is limited by the sensor’s resolution …


Modeling Of Fluid Injection For Hydraulic Fracturing Initiation In Porous Rock Formations, Krishna Adhikari Mar 2019

Modeling Of Fluid Injection For Hydraulic Fracturing Initiation In Porous Rock Formations, Krishna Adhikari

LSU Master's Theses

Hydraulic fracturing has been widely opted in recent times to simulate the unconventional reservoirs and thus, has become key a subject of interest in petroleum engineering. The stress concentration around the borehole affects the breakdown pressure and fracture reopening pressure during the hydraulic fracturing treatments. Thus, the state of stress around borehole wall and its surrounding rocks due to instantaneous drilling and a fluid injection at borehole surface needs to be determined accurately to initiate the hydraulic fractures. This research intends to derive the analytical stress solution of inclined borehole subjected to time-dependent fluid injection and in-situ stress, verify the …


Concentration Flow Cells For Efficient Salinity Energy Recovery With Carbonized Peat Moss And Molybdenum Disulfide Electrodes, Haihui Zhu Mar 2019

Concentration Flow Cells For Efficient Salinity Energy Recovery With Carbonized Peat Moss And Molybdenum Disulfide Electrodes, Haihui Zhu

LSU Master's Theses

The globally extractable salinity gradient (SG) energy from the mixing of seawater and river water is estimated to be 3% of worldwide electricity consumption. Here we applied carbonized peat moss (CPM) electrodes and molybdenum disulfide (MoS2) electrodes to a concentration flow cell that is capable of harvesting SG energy based on the electrode (pseudo-)capacitance together with the Donnan potential. The CPM electrodes were made from the visually inexhaustible peat moss by a facile pyrolysis process. With two identical CPM electrodes and a cation-exchange membrane, the cell produced a peak power density of 5.33 W m-2 and an …


Coastal Louisiana Landscape And Hurricane Storm Surge Evolution 1850 - 2110, Christopher George Siverd Mar 2019

Coastal Louisiana Landscape And Hurricane Storm Surge Evolution 1850 - 2110, Christopher George Siverd

LSU Doctoral Dissertations

The hurricane storm surge analysis presented in this dissertation examines surge response to changes in the Louisiana coastal landscape and Gulf of Mexico water level from 1850 to 2110. Land to water (L:W) isopleths, lines depicting areas of constant land to water ratio along the modern Louisiana coast, are utilized in the development of a simplified storm surge model that closely reproduces the surge output of a state-of-the-art detailed model. Eleven comparable storm surge models are constructed with each featuring a representation of the Louisiana coastal landscape circa 1850, 1890, 1930, 1970, 1990, 2010, 2030, 2050, 2070, 2090 and 2110. …


Quantitative Evaluation Of A Lightweight Sediment For A Physical Model Of The Lower Mississippi River, Mauricio Hooper Mar 2019

Quantitative Evaluation Of A Lightweight Sediment For A Physical Model Of The Lower Mississippi River, Mauricio Hooper

LSU Doctoral Dissertations

The Lower Mississippi River Physical Model (LMRPM), housed at the LSU Center for River Studies on the Baton Rouge, LA Water Campus, is a distorted, movable bed model comprising the lower 195 miles of the Mississippi River from Donaldsonville through the Head of Passes into the Gulf of Mexico. Since the LMRPM was designed to replicate the hydraulics (i.e., flow and river stages) and bulk non-cohesive sediment transport, the model lightweight sediment must replicate both the incipient motion and two-dimensional dune characteristics (height and length). In addition, the model scale and distortion require that the sediment time scale be determined …


Aerodynamic Flutter And Buffeting Of Long-Span Bridges Under Wind Load, Shuqian Liu Mar 2019

Aerodynamic Flutter And Buffeting Of Long-Span Bridges Under Wind Load, Shuqian Liu

LSU Doctoral Dissertations

With the continuous increase of span lengths, the aerodynamic characteristics of long-span bridges under external wind excitation have become much more complex and wind-induced vibration has always been a problem of great concern. The present research targets on the aerodynamic performance of long-span bridges under wind load with an emphasis on bridge flutter and buffeting.

For the aerodynamic flutter analysis of long-span bridges, the present research investigated the effects of the wind turbulence on flutter stability. The characterizations of the self-excited forces are presented in both the frequency-domain and in the time-domain, and the flutter analysis is conducted under both …


Characterization, Source Apportionment And Health Analysis Of Air Pollutants In India, Hao Guo Feb 2019

Characterization, Source Apportionment And Health Analysis Of Air Pollutants In India, Hao Guo

LSU Doctoral Dissertations

In recent years, severe pollution events occurred frequently in India, which are of significant concern of the public. However, limited studies have been conducted to understand the formation, sources and health effects of high pollution levels and the information for design of effective control strategies is urgently needed. First, criteria air pollutants data at 10 sites for 2017 in Delhi were analyzed to understand the current pollution status. The results show that annual fine particulate matter (PM2.5) concentrations exceeded the National Ambient Air Quality Standards (NAAQS), India of 60 µg/m3 at all sites. Source-oriented versions of the …


Low-Density Static Granular Media Filter Bed Turbidity Removal Model, Matthew Louque Jan 2019

Low-Density Static Granular Media Filter Bed Turbidity Removal Model, Matthew Louque

LSU Master's Theses

The scattering of light within a fluid, referred to as its turbidity, was investigated against the presence of suspended solids. A linear regression analysis was conduced against turbidity and the total count, combined surface area, and combined volume of the suspended particles for various surface water sources (lakes, rivers, indoor aquaculture systems). It was found that the total combined surface area of suspended particles had the best linear correlation to turbidity, with an adjusted R2 of 81.79%. This correlation was integrated with a current theoretical model for predicting solids removal across a granular bed to yield an Integrated Turbidity …


Modeling Of Leakage Through Fault-Zone Structures In Co2 Geological Storage, Dayna Rodriguez Zambrano Jan 2019

Modeling Of Leakage Through Fault-Zone Structures In Co2 Geological Storage, Dayna Rodriguez Zambrano

LSU Master's Theses

Faults intersecting target geological CO2 storage zones have important implications for storage integrity. Potential leakage pathways due to fluid over-pressurization are investigated in this project to ensure long-term containment of injected CO2. Numerical flow simulations coupled with a geomechanical module are presented in this work with the purpose of determining the extent of CO2 up-fault migration, the driving mechanisms of leakage and the corresponding response of quantified pore pressure and stress variations.

This study uses dual-continuum models performed by using CMG (2017) to correctly account of flow through fractures in a fault damage zone. Numerical simulations …