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Evaluation Of Comparative Damaging Effects Of Multiple Truck Axles For Flexible Pavements, Stefan Romanoschi, Athanassios Papagiannakis Dec 2018

Evaluation Of Comparative Damaging Effects Of Multiple Truck Axles For Flexible Pavements, Stefan Romanoschi, Athanassios Papagiannakis

Publications

This study aims at evaluating the effect of overlapping flexible pavement strain responses from truck axles that are not part of multiple axle configurations (i.e., tandem, triple and quad). For this purpose, a newly constructed pavement was instrumented with strain gauges installed at the bottom of the asphalt concrete base layer on US-287 south of Mansfield, TX. This pavement structure is typically used for medium- to high-volume roads in the South-Central region of the United States. The strain gauges were used to measure longitudinal and transverse strains under several passes of a test vehicle. This was a class 6 truck …

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Coastal Bridges Under Hurricane Stresses Along The Texas And Louisiana Coast, Adolfo Matamoros, Firat Testik Dec 2018

Coastal Bridges Under Hurricane Stresses Along The Texas And Louisiana Coast, Adolfo Matamoros, Firat Testik

Publications

The main objective of this study is to develop a high-resolution model capable of simulating the response of bridge structures to hydrodynamic loads for hurricane design conditions (i.e., surge height, wave height, and frequency) expected in the Texas-Louisiana coast. The model relied on Coupled Eulerian-Lagrangian (CEL) techniques where solids are simulated with Lagrangian meshes, while fluids are simulated using Eulerian meshes, and was calibrated using historical data from wave impact laboratory tests. Two high resolution models were created, the first of a tsunami wave impact test conducted at Oregon State University and the second of a bridge located in the …

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Development Of A Self-Powered Structural Health Monitoring System For Transportation Infrastructure, Aydin Karsilaya, Samer Dessouky, Athanassios Papagiannakis Dec 2018

Development Of A Self-Powered Structural Health Monitoring System For Transportation Infrastructure, Aydin Karsilaya, Samer Dessouky, Athanassios Papagiannakis

Publications

Roadways and bridges play an important role in the economic and social health of society by connecting commerce and people. Economic growth and population expansion pose considerable burden on the aging infrastructure (i.e., pavements and bridges). There is a pressing need to develop structural health monitoring (SHM) technologies capable of collecting infrastructure utilization data. Doing so inexpensively with self-powered systems will revolutionize infrastructure monitoring technology, and will improve decision making enabling roadway and bridge preservation. In this study, a self-powered battery-less structural health monitoring (SHM) system was developed. It is powered by a thermal energy harvester equipped with thermoelectric generators …

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Mitigating Traffic Congestion On I-10 In Baton Rouge, La: Supply- And Demand-Oriented Strategies & Treatments, Samir Ahmed, Osama Osman, Julius Codjoe Dec 2018

Mitigating Traffic Congestion On I-10 In Baton Rouge, La: Supply- And Demand-Oriented Strategies & Treatments, Samir Ahmed, Osama Osman, Julius Codjoe

Publications

The aim of this study is to develop a better understanding of the causes of traffic congestion on I-10 in the Baton Rouge, LA area, particularly at the I-10 Mississippi River Bridge, and to identify treatments and strategies to mitigate congestion at the bridge site. This study developed and calibrated a microsimulation model of I-10 (from Lobdell Highway in Port Allen to Highland Road, I-110 to Florida Street, and I-12 to Walker Road) and investigated several supply- and demand-oriented strategies. This includes: rehabilitation and utilization of the old Mississippi River Bridge on US-190 and the existing US-190/US-61 corridor, overall demand …

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Recruiting, Retaining, And Promoting For Careers At Transportation Agencies, Christofer Harper, Susan Bogus, Raghava Kommalapati, Doeun Choe Dec 2018

Recruiting, Retaining, And Promoting For Careers At Transportation Agencies, Christofer Harper, Susan Bogus, Raghava Kommalapati, Doeun Choe

Publications

State transportation agencies currently face complex challenges in recruiting and retaining the workforce necessary to function effectively. The situation exacerbates due to the number of employees from different generations that have to coexist with varying values, expectations, and principles. These agencies are primarily comprised of two generational groups: the baby-boomers, who are approaching retirement and occupy many managerial positions; and the millennials, who are demonstrating their interest in technology and demanding dynamism in their careers. This multiplicity of interest represents a challenge for human resources (HR) in addressing workforce issues and providing the necessary means to recruit and retain qualified …

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Research Incentive Programs For Closures Of Public And Private Grade Crossings, Julius Codjoe Dec 2018

Research Incentive Programs For Closures Of Public And Private Grade Crossings, Julius Codjoe

Publications

Vehicle-train crashes that occur at highway-rail crossings result in injuries, fatalities, and damage to equipment. In order to reduce the number of vehicle-train crashes, Federal Railroad Administration requires states which have challenges with crossing safety, including Louisiana, to develop a State Action Plan to improve grade crossing safety. Consequently, identification of specific solutions for improving safety at crossings was included in the 2015 Louisiana Transportation Plan as one of its objectives. This study seeks to identify and evaluate current and new incentive programs that encourage closure of at-grade railroad crossings to reduce the number of potential vehicle-train collision points, and …

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“How Is My Child’S Asthma?” Digital Phenotype And Actionable Insights For Pediatric Asthma, Utkarshani Jaimini, Krishnaprasad Thirunarayan, Maninder Kalra, Revathy Venkataramanan, Dipesh Kadariya, Amit Sheth Nov 2018

“How Is My Child’S Asthma?” Digital Phenotype And Actionable Insights For Pediatric Asthma, Utkarshani Jaimini, Krishnaprasad Thirunarayan, Maninder Kalra, Revathy Venkataramanan, Dipesh Kadariya, Amit Sheth

Publications

Background: In the traditional asthma management protocol, a child meets with a clinician infrequently, once in 3 to 6 months, and is assessed using the Asthma Control Test questionnaire. This information is inadequate for timely determination of asthma control, compliance, precise diagnosis of the cause, and assessing the effectiveness of the treatment plan. The continuous monitoring and improved tracking of the child’s symptoms, activities, sleep, and treatment adherence can allow precise determination of asthma triggers and a reliable assessment of medication compliance and effectiveness. Digital phenotyping refers to moment-by-moment quantification of the individual-level human phenotype in situ using data from …

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Observations Of Reduced Turbulence And Wave Activity In The Arctic Middle Atmosphere Following The January 2015 Sudden Stratospheric Warming, Colin C. Triplett, Jintai Li, Richard L. Collins, Gerald A. Lehmacher, Aroh Barjatya, David C. Fritts, Et. Al. Nov 2018

Observations Of Reduced Turbulence And Wave Activity In The Arctic Middle Atmosphere Following The January 2015 Sudden Stratospheric Warming, Colin C. Triplett, Jintai Li, Richard L. Collins, Gerald A. Lehmacher, Aroh Barjatya, David C. Fritts, Et. Al.

Publications

Measurements of turbulence and waves were made as part of the Mesosphere-Lower Thermosphere Turbulence Experiment (MTeX) on the night of 25–26 January 2015 at Poker Flat Research Range, Chatanika, Alaska (65°N, 147°W). Rocket-borne ionization gauge measurements revealed turbulence in the 70- to 88-km altitude region with energy dissipation rates between 0.1 and 24 mW/kg with an average value of 2.6 mW/kg. The eddy diffusion coefficient varied between 0.3 and 134 m2/s with an average value of 10 m2/s. Turbulence was detected around mesospheric inversion layers (MILs) in both the topside and bottomside of the MILs. These …

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Variation In Regional And Landscape Effects On Occupancy Of Temperate Bats In The Southeastern U.S., Benjamin D. Neece, Susan C. Loeb, David S. Jachowski Nov 2018

Variation In Regional And Landscape Effects On Occupancy Of Temperate Bats In The Southeastern U.S., Benjamin D. Neece, Susan C. Loeb, David S. Jachowski

Publications

Habitat loss, wind energy development, and the disease white-nose syndrome are major threats contributing to declines in bat populations in North America. In the southeastern US in particular, the recent arrival of white-nose syndrome and changes in landscape composition and configuration have driven shifts in bat species populations and distributions. Effective management strategies which address these large-scale, community-level threats require landscape-scale analyses. Our objective was to model the relationship between ecoregional and landscape factors and occupancy by all bat species in South Carolina, USA, during summer. We conducted acoustic surveys from mid-May through July 2015 and 2016 and evaluated temporally …

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Investigation Of Carrier Density And Mobility Variations In Graphene Caused By Surface Adsorbates, Hongmei Li, Xu Han, Anthony C. Childress, Apparao M. Rao, Goutam Koley Nov 2018

Investigation Of Carrier Density And Mobility Variations In Graphene Caused By Surface Adsorbates, Hongmei Li, Xu Han, Anthony C. Childress, Apparao M. Rao, Goutam Koley

Publications

Conductivity, carrier concentration and carrier mobility in graphene were investigated as a function of time in response to ionized donor and acceptor adsorbates. While a reduction in conductivity and hole density in graphene was observed upon exposure to a weak electron donor NH3, the carrier mobility was found to increase monotonically. The opposite behavior is observed upon exposure to NO2, which is expected based on its typical electron withdrawing property. Upon exposure to C9H22N2, a strong donor, it resulted in the transformation of graphene from p-type to n-type, although …

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Development Of Statewide Annual Average Daily Traffic Estimation Model From Short-Term Counts: A Comparative Study For South Carolina, Sakib Mahmud Khan, Sababa Islam, Md Zadid Khan, Mashrur Chowdhury, Nathan Huynh, Mohammad Torkjazi Nov 2018

Development Of Statewide Annual Average Daily Traffic Estimation Model From Short-Term Counts: A Comparative Study For South Carolina, Sakib Mahmud Khan, Sababa Islam, Md Zadid Khan, Mashrur Chowdhury, Nathan Huynh, Mohammad Torkjazi

Publications

Annual Average Daily Traffic (AADT) is an important parameter for traffic engineering analysis. Departments of Transportation continually collect traffic count using both permanent count stations (i.e., Automatic Traffic Recorders or ATRs) and temporary short-term count stations. In South Carolina, 87% of the ATRs are located on interstates and arterial highways. For most secondary highways (i.e., collectors and local roads), AADT is estimated based on short-term counts. This paper develops AADT estimation models for different roadway functional classes with two machine learning techniques: Support Vector Regression (SVR) and Artificial Neural Network (ANN). The models predict AADT from short-term counts. The results …

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Science Education Trajectories: Charting The Course For Teachers, Educators, Researchers, And Policymakers, Julie Luft, Brooke A. Whitworth, Amanda Berry, Shannon Navy, Vanessa Kind Nov 2018

Science Education Trajectories: Charting The Course For Teachers, Educators, Researchers, And Policymakers, Julie Luft, Brooke A. Whitworth, Amanda Berry, Shannon Navy, Vanessa Kind

Publications

Science teacher professional development is complex. Phases in a teacher’s career necessitate different professional learning opportunities. Furthermore, knowledge bases, practices, and attributes need to be cultivated during these times. For science teachers, it is not always evident how to link professional learning opportunities progressively toward different outcomes, including being a department head, teacher leader, curriculum developer, or even master teacher. In order to spur a discussion about purposeful teacher learning, we use a theory of transformative learning to examine research pertaining to the professional learning of science teachers. The result is a conceptual framework that suggests that teachers should build …

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Vortex Structures Inside Spherical Mesoscopic Superconductor Plus Magnetic Dipole, A. Ludu Nov 2018

Vortex Structures Inside Spherical Mesoscopic Superconductor Plus Magnetic Dipole, A. Ludu

Publications

We investigate the existence of multivortex states in a superconducting mesoscopic sphere with a magnetic dipole placed at the center. We obtain analytic solutions for the order parameter inside the sphere through the linearized Ginzburg-Landau (GL) model, coupled with mixed boundary conditions, and under regularity conditions and decoupling coordinates approximation. The solutions of the linear GL equation are obtained in terms of Heun double confluent functions, in dipole coordinates symmetry. The analyticity of the solutions and the associated eigenproblem are discussed thoroughly. We minimize the free energy for the fully nonlinear GL system by using linear combinations of linear analytic …

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Erosion Rate Equations For Coarse- Grained Materials Using A Small Flume Testing, Ghada Ellithy, Johannes L. Wibowo, Maureen K. Corcoran Nov 2018

Erosion Rate Equations For Coarse- Grained Materials Using A Small Flume Testing, Ghada Ellithy, Johannes L. Wibowo, Maureen K. Corcoran

Publications

Erosion rate of soils during a levee or dam overtopping event is a major component in risk assessment evaluation of breach time and consequently in determining the downstream consequences. There is uncertainty in estimation of the erosion rate especially for coarsegrained materials that comprise the outer shell layer of dams as well as homogenous levees that are constructed of such materials. In this paper, erosion rate results are presented on three soil mixes that share the same median grain size D50 of 2 mm, the fines content varies between zero and 20%, and the gravel content between zero and 30%. …

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Self-Healing Microcapsules As Concrete Aggregates For Corrosion Inhibition In Reinforced Concrete, Homero Castaneda, Marwa Hassan, Miladin Radovic, Jose Milla Nov 2018

Self-Healing Microcapsules As Concrete Aggregates For Corrosion Inhibition In Reinforced Concrete, Homero Castaneda, Marwa Hassan, Miladin Radovic, Jose Milla

Publications

Reinforced Concrete (RC) structures are vital to the US’s civil infrastructure for their strength and versatility. Unfortunately, RC elements deteriorate rapidly when exposed to corrosive environments. One possible solution is to extend the life of RC elements and systems using microencapsulated corrosion inhibitors to reduce the rebar corrosion rate. The capsules house an anodic corrosion inhibitor agent including calcium nitrate (CN) and triethanolamine (TEA). The integration of such microencapsulated materials will enhance the durability and extend the useful life by controlling the corrosion precursors and the corrosion process during damage evolution. Therefore, this work aims to develop and characterize the …

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Development, Training, Education, And Implementation Of Low-Cost Sensing Technologies For Bridge Structural Health Monitoring (Shm), Fernando Moreu, Chris Lippitt, Dilendra Maharjan, Marlon Aguero, Roya Nasimi Nov 2018

Development, Training, Education, And Implementation Of Low-Cost Sensing Technologies For Bridge Structural Health Monitoring (Shm), Fernando Moreu, Chris Lippitt, Dilendra Maharjan, Marlon Aguero, Roya Nasimi

Publications

Transportation infrastructure needs continuous monitoring. However, traditional inspections cost money and are conducted visually. New technologies for bridge monitoring are expensive and complex. This project involved developing cost-effective sensor technologies that can be applied towards the maintenance of railroad bridges by recording reference-free transverse displacement. More specifically, this project developed new applications of new technologies (Arduino, wireless smart sensors, drones, Hololens) and promoted workforce development with an emphasis on outreach of high-school students. This project was carried out in three main phases: (1) development and validation of technologies, (2) education and outreach to students, and (3) outreach to industry consisting …

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Sustainability-Based Long-Term Management Of Bridges Under Multi-Hazard Exposure, Mohamed Soliman Nov 2018

Sustainability-Based Long-Term Management Of Bridges Under Multi-Hazard Exposure, Mohamed Soliman

Publications

Bridges are under deterioration due to various mechanical and environmental stressors. Hydraulic-related hazards (e.g., flood and scour), aggressive environmental conditions, and seismic events (e.g., earthquake) are recognized as the most significant threats to the safety of bridges. In traditional risk assessment methods for structures susceptible to damage due to floods and other natural hazards (e.g., corrosion and seismic events), future hazard predictions are conducted using historic return periods and climate records. However, recent increase in flood intensity in central-southern states indicate that future hazard occurrence rate may not necessarily follow past trends. Accordingly, current design, assessment, and management methodologies should …

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Urban Agriculture And Small Farm Water Use: Case Studies And Trends From Cache Valley, Utah, Tyler Pratt, L. Niel Allen, David E. Rosenberg, Andrew A. Keller, Kelly Kopp Oct 2018

Urban Agriculture And Small Farm Water Use: Case Studies And Trends From Cache Valley, Utah, Tyler Pratt, L. Niel Allen, David E. Rosenberg, Andrew A. Keller, Kelly Kopp

Publications

The landscape of water in Utah is changing due to population growth, conversion of agricultural land to urban development, and increasing awareness of water scarcity. At the same time, Utah is experiencing a growing number of urban and small farms, but knowledge of water use in this sector is limited. Better understanding of what occurs at the field level on urban and small farms can aid state water use estimates and conservation efforts, and assist farmers in moving towards wiser water management. For the 2015 growing season, we performed irrigation evaluations for 24 urban and small farms in Cache Valley, …

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Comparative Venom-Gland Transcriptomics And Venom Proteomics Of Four Sidewinder Rattlesnake (Crotalus Cerastes) Lineages Reveal Little Differential Expression Despite Individual Variation, Erich P. Hofmann, Rhett M. Rautsaw, Jason L. Strickland, Matthew L. Holding, Michael P. Hogan, Andrew J. Mason, Darin R. Rokyta, Christopher L. Parkinson Oct 2018

Comparative Venom-Gland Transcriptomics And Venom Proteomics Of Four Sidewinder Rattlesnake (Crotalus Cerastes) Lineages Reveal Little Differential Expression Despite Individual Variation, Erich P. Hofmann, Rhett M. Rautsaw, Jason L. Strickland, Matthew L. Holding, Michael P. Hogan, Andrew J. Mason, Darin R. Rokyta, Christopher L. Parkinson

Publications

Changes in gene expression can rapidly influence adaptive traits in the early stages of lineage diversification. Venom is an adaptive trait comprised of numerous toxins used for prey capture and defense. Snake venoms can vary widely between conspecific populations, but the influence of lineage diversification on such compositional differences are unknown. To explore venom differentiation in the early stages of lineage diversification, we used RNA-seq and mass spectrometry to characterize Sidewinder Rattlesnake (Crotalus cerastes) venom. We generated the first venom-gland transcriptomes and complementary venom proteomes for eight individuals collected across the United States and tested for expression differences …

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Prediction And Rehabilitation Of Highway Embankment Slope Failures In Changing Climate, Navid Jafari, Anand Puppala Oct 2018

Prediction And Rehabilitation Of Highway Embankment Slope Failures In Changing Climate, Navid Jafari, Anand Puppala

Publications

Highway slopes constructed with clayey soil are prone to desiccation cracks due to wetting and drying weather cycle, which allows greater moisture infiltration into the embankment from precipitation. Fissures formed due to extended wetting and drying cycles allow water to seep deeper into the soil than surficial wetting and increase the water content. This increases the moisture content in the soil and results in reduction in shear strength to the fully softened strength. On the other hand, development of desiccation cracks and reduction of the soil matric suction ultimately result in higher hydraulic conductivity value which causes development of higher …

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Impacts Of Moisture On Asphalt Properties, Zahid Hossain Oct 2018

Impacts Of Moisture On Asphalt Properties, Zahid Hossain

Publications

Stripping related moisture damage has been recognized as one of the major pavement distresses since the early 1990s. The main objective of this study is to establish an effective test protocol to quantify moisture susceptibility of asphalt pavements. To this end, selective test methods (Texas Boiling test, Tensile Strength Ratio, Retained Stability, and Hamburg Wheel Test), and procedures based on surface chemistries and molecular-level mechanistic properties have been investigated in this study. Firstly, a comprehensive list of literature related to moisture damage in asphalts was reviewed. Based on the literature review, a detailed project plan and test matrix were developed. …

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A Better Way Of Farming, Stephanie Rains, Brooke A. Whitworth Oct 2018

A Better Way Of Farming, Stephanie Rains, Brooke A. Whitworth

Publications

No abstract provided.

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Comparative Venom-Gland Transcriptomics And Venom Proteomics Of Four Sidewinder Rattlesnake (Crotalus Cerastes) Lineages Reveal Little Differential Expression Despite Individual Variation, Erich Hofmann, Rhett M. Rautsaw, Jason L. Strickland, Matthew L. Holding, Michael P. Hogan, Andrew J. Mason, Darin R. Rokyta, Christopher L. Parkinson Oct 2018

Comparative Venom-Gland Transcriptomics And Venom Proteomics Of Four Sidewinder Rattlesnake (Crotalus Cerastes) Lineages Reveal Little Differential Expression Despite Individual Variation, Erich Hofmann, Rhett M. Rautsaw, Jason L. Strickland, Matthew L. Holding, Michael P. Hogan, Andrew J. Mason, Darin R. Rokyta, Christopher L. Parkinson

Publications

Changes in gene expression can rapidly influence adaptive traits in the early stages of lineage diversification. Venom is an adaptive trait comprised of numerous toxins used for prey capture and defense. Snake venoms can vary widely between conspecific populations, but the influence of lineage diversification on such compositional differences are unknown. To explore venom differentiation in the early stages of lineage diversification, we used RNA-seq and mass spectrometry to characterize Sidewinder Rattlesnake (Crotalus cerastes) venom. We generated the first venom-gland transcriptomes and complementary venom proteomes for eight individuals collected across the United States and tested for expression differences …

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Enhancing The Durability And The Service Life Of Asphalt Pavements Through Innovative Light-Induced Self-Healing Materials, Marwa Hassan Oct 2018

Enhancing The Durability And The Service Life Of Asphalt Pavements Through Innovative Light-Induced Self-Healing Materials, Marwa Hassan

Publications

The objective of this study was to evaluate the efficiency of a new generation of Ultraviolet (UV) light-induced selfhealing polymers in enhancing the durability and self-healing properties of asphalt mixtures. Self-healing polymers were successfully synthesized in the laboratory and were characterized using Fourier Transform Infrared Spectroscopy (FTIR). In addition, Thermogravimetric Analysis (TGA) results showed that the synthesized polymers achieved the required thermal stability to resist asphalt mixture production processes. Viscosity results showed that addition of 5% Recycled Asphalt Shingle (RAS) and/or 20% Reclaimed Asphalt Pavement (RAP) caused an increase in the viscosity of the binder blends. However, a reduction in …

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Evaluation Of The Performance And Cost-Effectiveness Of Engineered Cementitious Composites (Ecc) Produced From Region 6 Local Materials, Gabriel Andres Arce Amador, Tyson Rupnow, Marwa Hassan Oct 2018

Evaluation Of The Performance And Cost-Effectiveness Of Engineered Cementitious Composites (Ecc) Produced From Region 6 Local Materials, Gabriel Andres Arce Amador, Tyson Rupnow, Marwa Hassan

Publications

The project objective is to develop cost-effective Engineered Cementitious Composites (ECC) with locally available ingredients in Region 6 to address the deficiencies observed in ordinary concrete materials. The study explored the utilization of two types of river sands (coarse and fine), two types of PVA fibers (long and short), four levels of cement replacement with Class F fly ash, and the implementation of recycled crumb rubber in the performance of ECC materials. A total of 24 mix designs were prepared and evaluated in compression, tension, and bending to assess its mechanical properties. Furthermore, the cracking characteristics of the materials produced …

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Modeling Sulfate Attack In Modern Concrete For Building Sustainable And Resilient Infrastructure, Zachary Grasley Oct 2018

Modeling Sulfate Attack In Modern Concrete For Building Sustainable And Resilient Infrastructure, Zachary Grasley

Publications

External sulfate attack is a complex phenomenon and is manifested in the form of large expansion, cracking, and spalling depending on the exposure solution and material constituent properties. Several models were developed in the past to demonstrate sulfate attack mechanisms that account for the diffusion of sulfate ions into the porous concrete and the successive deformation triggered by the chemical reaction and precipitation of expansive agents. However, none of these models accounts for the effect of the migration of solvent water from the low solute concentration solution to high solute concentration solution driven by the osmotic pressure. Osmotic pressure is …

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In-Situ Mechanical Characterization For Compacted Aggregates, Douglas Cortes, Paola Bandini Oct 2018

In-Situ Mechanical Characterization For Compacted Aggregates, Douglas Cortes, Paola Bandini

Publications

The evaluation of compacted unbound aggregate layers is perhaps the most common undertaking in transportation-related projects. The assessment of compaction compliance in engineered fills, subgrades, subbases, and bases in roadways and railways is central to ensure longevity of ground transportation infrastructure. In many cases, premature failures in roadways that originate in the unbound aggregate layers can be traced back to inadequate compaction. These failures are preventable, provided the problem areas can be identified by a suitable field test during construction. The most widely used method for compaction assessment during construction is the nuclear density gauge (NDG) test. While the device …

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Bridge Inspecting With Unmanned Aerial Vehicles R&D, Paul Darby, Vijaya Gopu Oct 2018

Bridge Inspecting With Unmanned Aerial Vehicles R&D, Paul Darby, Vijaya Gopu

Publications

The project achieves through research including literature, on site interviews, and experimentation: 1) a recommendation for a UAV-based system to practically assist in routine bridge inspection work in the State of Louisiana, 2) the identification and description of advantages, disadvantages, and limitations in the use of UAVs for routing bridge inspection work in Louisiana, and 3) provided recommendations for future work. The Yuneec H520 aircraft and its E90 camera are recommended, as is the need for a boat to be included as part of the system. The recommended system has advantages in reaching portions of the bridge that are difficult …

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Use Of Rice Hull Ash (Rha) As A Sustainable Source Of Construction Material, Zahid Hossain, Ashraf Elsayed Oct 2018

Use Of Rice Hull Ash (Rha) As A Sustainable Source Of Construction Material, Zahid Hossain, Ashraf Elsayed

Publications

With the imminent shortage of natural resources, the need to find sustainable development is the highest in recent history. Therefore, this study examines the potential uses of Rice Hull Ash (RHA) as a sustainable cementitious material (SCM) in preparation of concrete. This study also assesses the use of RHA as an alternative of commonly used polymers in preparing high-grade asphalt binders. RHA is a potential sustainable solution because it is currently being treated as an agricultural waste material, yet its high silica content makes it a potential construction material. Three different sizes of RHA (600 µm, 150 µm, and 44 …

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Use Of Nanoclays As Alternatives Of Polymers Toward Improving Performance Of Asphalt Binders, Zahid Hossain, Ashraf Elsayed Oct 2018

Use Of Nanoclays As Alternatives Of Polymers Toward Improving Performance Of Asphalt Binders, Zahid Hossain, Ashraf Elsayed

Publications

The main goal of this study is to assess the feasibility of the use of nanoclay as an alternative to commonly used polymers such as styrene-butadiene-styrene (SBS), which are used to modify the performance grade (PG) of asphalt binders. Three types of nanoclay and two types of neat binders were selected for laboratory investigation. Different amounts (1, 2, and 3%) of nanoclays were used. A blending protocol has been developed to mix the nanoclay with the asphalt binder. Rotational Viscosity (RV), Dynamic Shear Rheometer (DSR), Optical Contact Analyzer (OCA) and Atomic Force Microscope (AFM) were conducted to evaluate the properties …

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