Engineering Commons^™

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 …

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 …

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

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, …

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

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

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

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

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 …

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

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

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

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 …

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

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 …

Effect Of Different Traffic Signal Control Plans On Simulation Of Hurricane Evacuation Traffic, Divya Kolasani

LSU Master's Theses

The majority of hurricane evacuation modeling studies concentrate on evacuation traffic on freeways with relatively little attention being given to traffic on arterials. This study is focused on evaluating the evacuation efficiency of a network under different traffic signal settings on arterials using microscopic simulation. This is achieved by changing the traffic signal settings from existing signal timing plans to flashing yellow on major evacuation routes and flashing red on cross streets, for a given evacuation order. Time-dependent origin-destination matrices for hurricane evacuation up to 72 hours away from landfall for No Evacuation order, as well as a Voluntary/Mandatory Evacuation …