Engineering Commons^™

Hot Wire Anemoteter, Michael S. Potash, Albert D. Helfrick

Publications

A hot wire anemometer circuit has a calibrate subcircuit and an operate subcircuit which are selectively invoked via a user-activate mode switch. The calibrate subcircuit includes a detector configured to compare an amplified sensor voltage with an amplified drive voltage and output an indicator signal when the two voltages match. The drive voltage is derived from a user-adjusted drive resistance of a bridge subcircuit. The operate circuit includes a feedback loop which provides a signal to a bride node of a bridge circuit. After a sensor is connected to the anemometer circuit, the drive resistance is adjusted until the indicator …

Relationship Between Road Network Characteristics And Traffic Safety, Hatim Sharif, Samer Dessouky

Publications

The Transportation and Capital Improvement of the City of San Antonio, Texas Department of Transportation (TxDOT) and other related agencies often make several efforts based on traffic data to improve safety at intersections, but the number of intersection crashes is still on the high side. There is no one size fits all solution for intersections and the City is often usually confronted with doing best value option analysis on different solutions to choose the least expensive yet more advancements. The goal of this project was to obtain the relationship between road network characteristics and public safety with a focus on …

Simplified Approach For Structural Evaluation Of Flexible Pavements At The Network Level, Mena Souliman, Stefan Romanoschi, Samer Dessouky

Publications

Currently, there are few available simple procedures to identify structurally weak pavement sections utilizing Falling Weight Deflectometer (FWD) data at the network level (e.g., city, state or province). A simple method is required to determine the structural condition of pavement sections that can be directly implemented and automated in current pavement databases. The objective of this research study is to develop a simple analysis method to determine the structural condition of pavement sections utilizing the currently available non-destructive testing (NDT) deflection measurement devices at the network level that can be directly implemented and automated in the database of a typical …

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 …

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 …

Use Of Ultra-High-Performance Fiber-Reinforced Concrete (Uhp-Frc) For Fast And Sustainable Repair Of Pavements, Shih-Ho Chao

Publications

This research presents a new methodology, which enables streets, roads, highways, bridges, and airfields to use an advanced fiber-reinforced concrete material, which can delay or prevent the deterioration of these transportation infrastructure when subjected to traffic and environmental loadings. The major problem of concrete is its considerable deterioration and limited service life due to its brittleness and limited durability. As a result, it requires frequent repair and eventual replacement, which consumes more natural resources. Ultra-high-performance fiber-reinforced concrete (UHP-FRC) introduces significant enhancement in the sustainability of concrete structures due to its dense microstructure and damage-tolerance characteristics. These characteristics can significantly reduce …

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 …

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 …

A Comprehensive Reliability-Based Framework For Corrosion Damage Monitoring And Repair Design Of Reinforced Concrete Structures, Homero Castaneda, Aydin Karsilaya, Ayman Okeil, Mahmoud Reda Taha

Publications

In this work, we developed a comprehensive framework for corrosion management of reinforced concrete (RC) structures. This framework includes critical steps of an effective approach to quantify the damage evolution as well as providing the timeframe for effective maintenance/repair strategies for corrosion assessment in RC structures. The framework included several activities including the use of indirect and direct inspection tools, theoretical development for damage prediction, experimental measurements and theoretical development of repair time based on reliability. The uniqueness of the framework is the integration of deterministic modeling of corrosion damage evolution by using mechanistic analysis with statistical modeling on corrosion …

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 …

Integrated Health Monitoring And Reinforcement Of Transportation Structures With Optimized Low-Cost Multifunctional Braided Cables, Ibrahim Karaman, Darren Hartl

Publications

The objective of this research study is to design, fabricate, and characterize multifunctional high strength and self-sensing braided cables and structures using novel Fe-based shape memory alloys (SMAs). The system exploits unique properties of recently developed low-cost super-elastic FeMnAlNi SMAs, which enables excellent super-elastic properties, high strength, and self-sensing in structural health monitoring (SHM) systems. This novel material technology can be coupled with modeling efforts that allow for accurate prediction of both the materials and structural response during sensing. At the conclusion of the project, we have demonstrated that with careful design of processing parameters, it is possible to control …

Investigating Problem Of Distracted Drivers On Louisiana Roadways, Xiaoduan Sun

Publications

Due to the escalating usage of cellphone and social networking, distracted driving is and will remain as one of the most serious problems faced by Departments of Transportation (DOTs) and law enforcement agencies. Under the aim of in-depth investigation of distracted driving crashes in Louisiana, the specific objectives of this study are: (1) reviewing the crash reports for the quality of distracted driving crash reporting, (2) analyzing distracted driving-related crashes through regression model and data mining algorithm to link the severity of distracted driving crashes with the contributing factors collected in crash data, (3) investigating the observable characteristics of distracted …

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 …

Standardization Roadmap For Unmanned Aircraft Systems, Version 1.0, Kristine Kiernan, Christian Janke, Kenneth Witcher

Publications

This Standardization Roadmap for Unmanned Aircraft Systems, Version 1.0 (“roadmap”) represents the culmination of the UASSC’s work to identify existing standards and standards in development, assess gaps, and make recommendations for priority areas where there is a perceived need for additional standardization and/or pre-standardization R&D.

The roadmap has examined 64 issue areas, identified a total of 60 gaps and corresponding recommendations across the topical areas of airworthiness; flight operations (both general concerns and application-specific ones including critical infrastructure inspections, commercial services, and public safety operations); and personnel training, qualifications, and certification. Of that total, 40 gaps/recommendations have been identified as …

Fiber Element-Based Nonlinear Analysis Of Concrete Bridge Piers With Consideration Of Permanent Displacement, Mokhtar Ansari, Farhad Daneshjoo, Amir Safiey, Naser Safaeian Hamzehkolaei, Maryam Sorkhou

Publications

Utilization of fiber beam-column element has gained considerable attention in recent years due mainly to its ability to model distributed plasticity over the length of the element through a number of integration points. However, the relatively high sensitivity of the method to modeling parameters as well as material behavior models can pose a significant challenge. Residual drift is one of the seismic demands which is highly sensitive to modeling parameters and material behavior models. Permanent deformations play a prominent role in the post-earthquake evaluation of serviceability of bridges affected by a near- fault ground shaking. In this research, the influence …

“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 …

Systems And Methods For Noise Mitigation For Hybrid And Electric Aircraft, Lenny Gartenberg, Richard P. Anderson, Borja Martos

Publications

A system and method of noise mitigation for hybrid and electric aircraft, the aircraft having a controllable pitch propeller or rotor(s) with a plurality of blades. The propeller or rotor(s) are driven by a drive system to provide thrust for the aircraft, and the blades of the propeller or rotor(s) are further movable about pivot axis to vary a pitch thereof. A controller on-board the aircraft is operable to cause rotation or movement of the blades of the propeller or rotor(s) about their pivot axis to alter and/or focus at least one aspect of the propeller generated noise to reduce …

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 …

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 …

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 …

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 …

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 …

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 …

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%. …

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, …

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 …

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 …

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 …

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 …

Development Of A Self-Healing And Rejuvenating Mechanisms For Asphalt Mixtures Containing Recycled Asphalt Shingle, Marwa Hassan

Publications

The objective of this study was to test the hypothesis that hollow-fibers encapsulating a rejuvenator product could improve both self-healing, rejuvenation, and mechanical properties of asphalt mixtures. Hollow-fibers containing a rejuvenating product were synthesized via a wet spinning procedure with sodium-alginate polymer as the encapsulating material. An optimization of the production parameters for the synthesis of fibers was performed to develop fibers suitable for high-temperature and shear stress environment typical of asphalt mixture production. A self-healing experiment was conducted to evaluate the healing/rejuvenation capabilities of sodium-alginate fibers in asphalt mixtures with varying types of binders and recycled materials. Based on …