Engineering Commons^™

The Generation And Transport Of Charged Aerosols: Fundamental Study And Applications In Medicine And Energy Conversion, Hao Zhou

McKelvey School of Engineering Graduate Student Theses & Dissertations

Charged aerosols have significant implications in the field of functional material synthesis, pharmaceutical coating, and drug delivery. Electrospray systems are an effective methodology for generating highly charged monodispersed droplets in the size range from nanometer to micrometer. The prediction of surface charge, size and morphology of nanoparticles resulting from charged droplets are highly required for the precise control of nanoparticle properties and their effective utilization. However, the evolution of charged droplet is not well understood due to the existence of coulombic fission and ion evaporation processes. Thus, the goal of this dissertation is to elucidate how the precursor properties and …

Role Of Water Chemistry In Lead Release During Drinking Water Supply And Augmentation, Anushka Mishrra

McKelvey School of Engineering Graduate Student Theses & Dissertations

Lead is a toxic heavy metal and legacy contaminant in drinking water that can be released from lead service lines and lead-containing premise plumbing. Lead concentrations in water are sensitive to changes in water chemistry. The extent of lead release is often driven by the solubility of the corrosion products formed on the interior of the pipes. Therefore, it is critical to advance our understanding of the extent of lead released from different lead-based plumbing materials at equilibrium and the ability to control lead when it exceeds the regulatory levels. Lead measured in the 1st liter of water collected from …

Photochemical Formation Mechanisms And Applications Of Mn Oxide Nanomaterials, Zhenwei Gao

McKelvey School of Engineering Graduate Student Theses & Dissertations

Manganese (Mn) oxides are ubiquitous in aquatic and terrestrial environments, and the rich redox chemistry of manganese is of interest in engineered systems, such as batteries and water oxidation catalysts. Mn oxides have large surface areas and are highly active in adsorption and redox reactions. Our research group recently reported photochemically-assisted abiotic inorganic oxidation of Mn2+(aq) to δ-MnO2 nanosheets in the presence of nitrate and without a microorganism, demonstrating that abiotic Mn oxidation processes are not negligible. My doctoral work focuses on investigating the effects of various aquatic chemistry parameters, including reactive oxygen species (ROS), peroxyl radical (ROO•), reactive halogen …

Advanced Nanomaterials And Module Designs For Efficient Photothermal Water Treatment, Deoukchen Ghim

McKelvey School of Engineering Graduate Student Theses & Dissertations

Water scarcity is one of the most serious challenges that human beings face, and the demand for clean water will continuously increase as populations grow. Creating potable water from saline water is an important way to meet global freshwater demands. However, current desalination techniques require high energy consumption and a large scale to be efficient, restricting their utilization in remote and underdeveloped areas. These constraints motivate the development of sustainable water treatment methods that can be used with less energy input, in small modular configurations, and in off-grid water treatment systems. As an abundant and renewable energy source, sunlight has …

Anti-Washout Concrete: An Overview, Hao Lu, Xiao Sun, Hongyan Ma

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Anti-washout concrete (AWC) is a special cement-based material that can be directly employed in underwater environments without dispersion. It was developed around 50 years ago, and more than 150 journal articles and technical reports have been published. This paper provides a holistic review about the basic fresh-state and hardened-state properties of the AWC, such as water (washout) resistance, consistency, bleeding and segregation resistance, mechanical properties, and durability, as well as relevant testing methods. The discrepancies between AWC's characteristics and those of conventional concrete are clearly presented. The mixture compositions, supplementary cementitious materials (SCMs), and other conditions that affect AWC's performance …

The Use Of Gpr To Investigate The Effect Of Steel Fiber Distribution On The Mechanical Behavior Of Frc, Paola Machado Barreto Manhães, José Tavares Araruna Júnior, Genda Chen, Neil Lennart Anderson, Erik Valloti Pereira, Flávio De Andrade Silva

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The present work focuses on the steel fiber distribution in self-consolidating concrete short beams. The objective is to assess the feasibility of the ground penetrating radar (GPR) in evaluating the homogeneity of fibers within concrete materials, for use in testing laboratories to study the modes of placing and compaction employed for preparing specimens during quality control or material development. Self-consolidating concrete beams were cast, tested, and evaluated. A GPR survey employing a concrete scanning system with a shielded 1.2 GHz center frequency was performed on self-consolidating casted short beams just before a monotonic four-point bending test was carried out. After …

Experimental Performance Evaluation Of A Convective Thermoelectric Building Envelope For Building Heating And Cooling, Xiaoli Liu, Kazuaki Yazawa, Ming Qu, Orkan Kurtulus, Brian Norton, Niall Holmes Dr., Ruchita Jani, Jorge Kohanoff, Lorenzo Stella, Conrad Johnston, Hongxi Yin

Articles

The thermoelectric building envelope (TBE) integrates thermoelectric materials with the building envelope for active space heating and cooling. The advantage of TBE heating and cooling includes its significantly low-profile design and no refrigerant use. Although there are existing studies evaluating TBE performance, they were based on limited operating conditions. The study aims to experimentally evaluate the heating and cooling performance of a TBE prototype under various operating conditions. The TBE prototype was installed between two psychrometric chambers, which simulated indoor and outdoor conditions. The prototype was tested at an indoor temperature of around 22.35–23.58 degrees C and outdoor temperatures from …

Incorporating Geopolymer Binders To Fully Utilize Recycled Concrete Aggregates, Matthew Upshaw

LSU Doctoral Dissertations

This study aims to develop a geopolymer concrete binder that will yield desirable strength and durability characteristics when applied to recycled aggregate concrete. In order to achieve this, a geopolymer binder consisting of a metakaolin-silica fume aluminosilicate source material blend activated by potassium-based alkaline solutions is developed and used in place of ordinary Portland cement (OPC) with four different levels of recycled aggregate replacement ratios. The properties of these concretes were analyzed and compared with the properties of OPC concretes produced with the same replacement ratio levels. The results showed that the geopolymer recycled aggregate concrete (GRAC) achieved greater than …

Dataset For Large-Scale, Lateral-Torsional Buckling Tests Of Continuous Beams In A Grillage System, Ahmed Rageh, C. Shawn Sun, Daniel G. Linzell, Jay A. Puckett

Department of Civil and Environmental Engineering: Faculty Publications

A number of large-scale tests of a grillage system are summarized and reduced data are provided. The tests were completed in association with a Louisiana Transportation Research Center (LTRC) project for the Louisiana Department of Transportation and Development (LA DOTD) whose goal was to better quantify behavior and limit states of steel bridge floor systems to refine longitudinal member (stringer) load- rating calculations. A number of tests focused on the behavior of the stringers resting on transverse members (a floorbeam), a system akin to a grillage. The system was proportioned with the expectation that stringer lateral-torsional buckling, a key steel …

Evaluation Of Flood Damage On Cross Laminated Timber Wall Configurations, Mustafa Nezih Kaya

Theses and Dissertations

Greenhouse gas emissions are one of the critical factors that affect climate change, increasing flooding risk and threatening human life. The use of traditional construction materials is responsible for a higher percentage of global greenhouse gas emissions when compared to the use of sustainable materials in the construction industry. The substitution of current building materials with sustainable materials is essential to reduce greenhouse gas emissions and positively influence climate change when the current construction demand in the world is considered. Wood is one of the primary environmentally friendly construction materials in regard to high carbon storage and low carbon emissions. …

Mechanical Responses Of Soil-Geosynthetic Composite (Sgc) Mass Under Failure Load, Meen-Wah Gui, Truc Phan, Thang Pham

Civil Engineering Faculty Publications

There is an increasing awareness on the major benefits of using soil-geosynthetic composite (SGC) to achieve and maintain the stability of earth-filled embankment. Unlike the mechanically stabilized earth wall, the mechanism of the composite mass is still not fully understood. For examples, current analyses have been limited to an SGC mass with a reinforcement spacing Sv of 0.2 m only; the combined effect of reinforcement and backfill properties is rarely studied; the equation for the estimation of the load-carrying capacity of the SGC mass has only been validated for backfill with maximum particle size dmax between 10 mm and 33 …

The Potential Of Mixed-Species Biofilms To Address Remaining Challenges For Economically-Feasible Microalgal Biorefineries: A Review, Rebecca J. Wicker, Eilhann Kwon, Eakalak Khan, Vinod Kumar, Amit Bhatnagar

Civil and Environmental Engineering and Construction Faculty Research

Several key challenges are hindering large-scale cultivation of microalgae for industrial purposes, including wastewater treatment, carbon capture, biomass production, and renewable energy production. These challenges are closely related to efficacy of 1) resource utilization, 2) biomass production, and 3) harvesting. This review describes how attached or biofilm cultivation of microalgae and/or cyanobacteria with heterotrophic bacteria in consortia could simultaneously resolve these technical obstacles, thereby reducing monetary and energetic costs of producing microalgal bioenergy. Symbiotic relationships between these organisms reduces the need for aeration or exogenous supplementation of nutrients. Additionally, this review details how increasing biodiversity correlates with diversity of functionality …

2022 Technical Program, Inspire - University Transportation Center

INSPIRE-UTC Annual Meetings

INSPIRE University Transportation Center 2022 Annual Meeting
August 1-2, 2022

Effect Of Varying Amounts Of Sandstone On The Performance Of Asphalt Mixtures In Arkansas, David Murphy

Graduate Theses and Dissertations

There are many different species and subspecies of aggregate used across the state of Arkansas, and the rest the country. However, it cannot be presumed that the amount and type of these aggregates will be compatible with the commonly used asphalt binder of an area; this can lead to performance issues and premature pavement damage. It has been suspected in Arkansas that an excessive amount of sandstone in asphalt mixtures may be a culprit of some of these premature pavement damage issues, especially regarding the moisture susceptibility of a pavement. This study aimed to analyze the performance effects of using …

Development Of Deep Shear Wave Velocity Profiles And An Approach To Generate Site Signature Consistent Pseudo Shear Wave Velocity Profiles In The Mississippi Embayment, Ashraf Kamal Himel

Graduate Theses and Dissertations

This dissertation details the development of a surface wave method (SWM) technique to generate deep shear wave velocity profiles (VS profiles), applying this technique at 24 sites across the Mississippi embayment and developing an approach to generate pseudo site signature consistent VS profiles from velocity functions and fundamental frequency. In the presented SWM technique, active and passive source surface wave measurements are inverted along with fundamental frequency to develop a site signature consistent VS profile. Multiple transformation methods, including MSPAC, HRFK and FK are used to resolve experimental dispersion data from surface wave measurements. SWM VS profile at the Central …

Investigations Into Flange Surface Friction Effects On Shear Stud Load Transfer In Composite Bridge Girders, Callie Clark

Graduate Theses and Dissertations

Composite bridge behavior is commonly achieved through headed shear studs welded tothe steel girder flange and embedded in the concrete deck. Current AASHTO provisions for estimating demands on shear studs during service-level loading consider only bearing load transfer, neglecting adhesion bonding and friction load transfer between the concrete deck and girder flange. Quantifying alternative load transfer mechanisms across the steel-concrete interface may result in improved steel bridge economy by reducing the number of studs required in a composite girder design. This study investigates the effects of flange surface friction (considering various coatings) on resulting stud demands using both experimental testing …

Initial Exploration Of Reduced Gyrations For Arkansas Asphalt Mix Designs, Jocie L. Baker

Graduate Theses and Dissertations

The most common distresses in asphalt pavement are cracking and rutting. These distresses plague almost every asphalt roadway in the world. Finding ways to mitigate these distresses will improve the performance of asphalt pavements. One way to combat the premature cracking of asphalt in the field is to ensure there is enough asphalt binder within the mix. This will help the flexibility of the asphalt undergoing large loads and deformation. However, it is widely accepted that mix designs across the country lack the appropriate amount of asphalt binder in their mixes, causing dry mix designs that are subject to cracking …

Multisorb: A Low-Cost Approach To Remove Multiple Metals And Organics From Leachate And Wastewater, Mithila Chakraborty

Civil Engineering Dissertations - Archive

ABSTRACT: Landfill leachates are considered now as a reusable source of water. Even irrigation projects are now considering use of non-traditional water sources, including treated wastewater, to augment supplies. Treated wastewater or leachate, however, may still contain many inorganic and organic pollutants of emerging concern, because traditional wastewater treatment plants are unable to remove all of them. Adsorbents have been demonstrated to effectively remove heavy metals and recalcitrant organics from leachate/wastewater more effectively, at lower cost, and using less chemicals and energy than many competing techniques. A single adsorbent with one pre-treatment, however, is not effective for simultaneously removing different …

Design Of Crack Attenuating Mix Using Waste Plastic, Shruti Singh

Civil Engineering Dissertations - Archive

Plastic has many good properties such as inexpensiveness, light weightedness and durability, but it comes with one major catch i.e., its ‘indestructibility’. Plastic waste is now omnipresent and highlights that all plastic ever produced still exists in some shape or form either as macro, micro or nano plastics, making it one of the greatest challenges our planet is facing today. At the same time many existing pavements are experiencing structural and functional deficiencies due to rapid growth in traffic volume. This has led to an ever-increasing rise in construction and rehabilitation cost. So, an alternative has been explored through this …

Identifying The Optimal Combination Of Critical Roadside Slope Segments Susceptible To Rainfall-Induced Failures For Minimizing Vulnerability Of Highway Networks, Anil Baral

Civil Engineering Dissertations - Archive

The stability of roadside slopes is vital for the smooth operation of the highway transportation system. The failure of slopes adjacent to the highway corridors adversely impacts the network users and network operators. The network users are subjected to delays through speed restrictions, stoppage, and diversions due to the blockage of a motorway. The network operators face the burden of implementation and finance of emergency slope repairs. Proactive rehabilitation of slopes helps to reduce roadside slope failures and minimize the disruption of transportation networks resulting from rainfall-induced slope failures. However, all the slope segments susceptible to rainfall-induced failures cannot be …

Experimental Study Of Flow Characteristics And Geometry Of Scour Hole Around Cylindrical Piers Subject To Wave And Current, Qazi Ashique E Mowla

Civil Engineering Dissertations - Archive

This thesis concerns the unique flow structure around bridge piers under the wave and current conditions. The flow characteristics around piers may change depending on the flow conditions and geometry of the pier. These flow structures imprint themselves on the streambed as scour holes. Laboratory experiments were conducted to investigate the changes that occur in the flow pattern and in the geometric pattern of scour holes around piers in waterbodies subject to waves and currents. Physical models of two piers with different diameters (19 mm and 50 mm) were built and installed in a sediment bed. A total of 19 …

Integrating Environmental Contamination Perceptions Of Artisanal And Small-Scale Mining Into Environmental Responses Across Spatial Scales, Michelle Schwartz

Civil Engineering Dissertations - Archive

ABSTRACT: Artisanal and small-scale gold mining (ASGM) is of significant interest to the international research community, government officials, and non-governmental organizations due to its large environmental footprint and its presence in over 70 countries worldwide. Despite the health and environmental concerns associated with mercury use in ASGM and the increased awareness at the international level, attempts to address environmental contamination has faced resistance as they often fail to account for the real-world conditions at sites of concern. Additionally, national and international interventions have fallen short when addressing ASGM pollution, calling for a new engineering approach towards ASGM-related projects. The purpose …

Development Of Multi Criteria Decision-Making Model To Evaluate The Adoption Effectiveness Of Electronic Ticketing (E-Ticketing) In Highway Construction Projects, Karthik Subramanya

Civil Engineering Dissertations - Archive

Highway and bridge construction projects are subject to cost and schedule overruns, as well as workforce shortages in remote locations, both of which can result in disputes over the quality of the end product. State departments of transportation (DOTs) are constructing and managing more highway projects than ever before despite limited funds and a shortage of inspectors. The construction of highway infrastructure has devoted significant resources towards e-Construction to reduce the paperwork and automate the tasks in daily operations. Electronic Ticketing (e-Ticketing) is one such component of e-Construction that aids in the digital transfer of material tickets such as asphalt …

Experimental Study Of Flow Characteristics And Geometry Of Scour Hole Around Cylindrical Piers Subject To Wave And Current, Qazi Ashique E Mowla

Civil Engineering Theses - Archive

This thesis concerns the unique flow structure around bridge piers under the wave and current conditions. The flow characteristics around piers may change depending on the flow conditions and geometry of the pier. These flow structures imprint themselves on the streambed as scour holes. Laboratory experiments were conducted to investigate the changes that occur in the flow pattern and in the geometric pattern of scour holes around piers in waterbodies subject to waves and currents. Physical models of two piers with different diameters (19 mm and 50 mm) were built and installed in a sediment bed. A total of 19 …

Sustainable And Inclusive Engineering: The Use Of Mentors And Sustainable Remediation To Increase The Presence Of Underrepresented Groups In Engineering, Nathaniel L. Steadman

Civil Engineering Theses - Archive

The recruitment and retention of underrepresented groups in engineering, such as women, has been a priority for many decades to diversify the profession to meet the current demand for engineers. Unfortunately, barriers continue to inhibit the recruitment and retention of underrepresented students in engineering, thus reducing the impact of these efforts. A potential barrier is a lack of social connection to the technical problem definition, design, and decision-making that engineers utilize, prioritizing technical knowledge over social. Previous research has theorized that the incorporation of social considerations in technical engineering design increases interest in engineering for underrepresented groups. The purpose of …

An Experimental Investigation Of Icephobicity And Hydrophobicity Of Concrete Surface Treated With Pavix, Hussein Hashemi Senejani

Civil Engineering Theses - Archive

High ice adhesion is a significant problem in several industries. The majority of practical issues brought on by ice adhesion are still not fully resolved, and the ice-adhesion mechanism is still poorly understood. Ice adhesion is a complex phenomenon that becomes more intricate when salt is involved, as in many marine cases. Reducing ice adhesion by generating hydrophobic surfaces might be advantageous in many applications as a passive ice removal strategy. Lowering adhesion may reduce friction, abrasion, and damage to structures in a maritime environment, as well as any surface prone to ice development. This process may also be utilized …

Sustain Water Conservation Behaviors Using Nonparametric Ranking And Social Marketing, Mahmudur Rahman Aveek

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Circulation of water use feedback and conservation messaging are strategies implemented to reduce water demand on a short-term (seasonal) basis. Often considered a less impactful strategy than other tactics such as price increments and usage restrictions, authorities mostly use feedback in informational campaigns with a focus to apprise users about their water use. Such conservation programs have had limited success that has been attributed to the fact that the information provided with the feedback campaigns was generic and did not motivate users enough to sustain their water-saving behaviors. However, the advent of disaggregation technologies that can provide appliance-wise water use …

Advancing The Cyberinfrastructure For Smart Water Metering And Water Demand Modeling, Nour A. Attallah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With rapid growth of urban populations and limited water resources, achieving an appropriate balance between water supply capacity and residential water demand poses a significant challenge to water supplying agencies. With the recent emergence of smart metering technology, where water use can be monitored and recorded at high resolution (e.g., observations of water use every 5 seconds), most existing research has been aimed at providing water managers with detailed information about the water use behavior of their consumers and the performance of water using fixtures. However, replacing existing meters with smart meters is expensive, and effectively using data produced by …

Cuo Nanoparticles Solubility As Influenced By Soil Pore Water, Native Microorganisms, And Wheat Rhizosphere Chemistry In A Sand Matrix, Dakota Sparks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nanoparticles (NPs) are particles less than 100 nm (~4 millionths of an inch) in a direction. NPs, due to their small size, are used in a variety of products, such as silver (Ag) NPs as an antimicrobial in clothes. Copper Oxide (CuO) NPs are used in electronics as semiconductors and other fields as antimicrobials and purposefully or accidentally end up in the environment. Copper (Cu) is a necessary nutrient for plants, but at higher amounts is toxic to plants and beneficial soil microbes.

In order to understand how the CuO NPs interacts with plants, wheat seedlings were grown in sand …

Passage Probability Of Woody Debris Elements And Accumulations At I- And V-Shaped Rock Weirs, Kathryn Margetts

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The transport and accumulation of driftwood or large woody debris (LWD) in mountain streams is a natural part of catchment health and river connectivity. At hydraulic structures, the presence of LWD may impact flow efficiency and influence upstream water depth. LWD has been studied at a variety of spillways and weir types, however, little is known about its interaction at rock weirs. This study investigated factors affecting the passage of individual LWD elements and any LWD accumulations at rock weirs, as well as potential impacts upstream of LWD accumulations through field-informed scaled model testing. Observations of LWD at rock weirs …