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Articles 61 - 90 of 107
Full-Text Articles in Transportation Engineering
Characterizing Truck Parking Shortages In Arkansas: A Data Analytical Approach, Morgan Hartsell
Characterizing Truck Parking Shortages In Arkansas: A Data Analytical Approach, Morgan Hartsell
Industrial Engineering Undergraduate Honors Theses
The Truck Parking Problem occurs when drivers have met the daily driving limit and encounter a decision between driving over time or parking in unauthorized locations. This research applies data analytics to gain further knowledge to characterize the truck parking shortage in Arkansas. Truck parking shortages are a serious problem that truck drivers face daily and is complex due to Hours of Service (HOS) regulations restrictions on legal parking areas and design. Existing research includes a one-day annual survey which compiles where public rest stops, businesses, and private rest stops are utilized by truck drivers. This research expands on the …
Structural Design Guidelines For Pervious Concrete Pavements, April Smith
Structural Design Guidelines For Pervious Concrete Pavements, April Smith
Civil Engineering Undergraduate Honors Theses
Pervious pavements have gained popularity in recent years as the transportation industry focuses on sustainability and environmental impact. This research investigated the structural design of pervious concrete pavements. There is no standard design method; therefore, the goal was to lessen ambiguity surrounding the use of pervious concrete for pavement structures. By characterization of the rigid pavement design equation from the 1993 AASHTO Structural Design Guide for Design of Pavement Structures through laboratory exploration and review of existing literature, a guide was created to assist engineers in the design of pervious concrete pavements.
Exploring The Compactability And Workability Of Rap, Elizabeth Poblete
Exploring The Compactability And Workability Of Rap, Elizabeth Poblete
Civil Engineering Undergraduate Honors Theses
Despite its economic and environmental benefits, the widespread use of Cold In-Place Recycling (CIR) is currently inhibited, to some degree, by a lack of laboratory testing and evaluation, specifically in the areas of compactability and workability of the reclaimed mixture stabilized with asphalt emulsion. The purpose of this study was to explore the influence of admixtures in CIR using modified Superpave Gyratory Compactor (SGC) compaction metrics. The primary stabilization technique considered in this research was asphalt emulsion, an application in which asphalt binder is suspended in water, allowing it to be stored and applied at ambient temperature, rather than the …
Development Of Anti-Icing Airfield Heated Pavement Systems Using Solar Energy, Joseph Daniels
Development Of Anti-Icing Airfield Heated Pavement Systems Using Solar Energy, Joseph Daniels
Graduate Theses and Dissertations
This dissertation analyzes developing and assessing the viability of an anti-icing airfield heated pavement system using solar energy. This study includes two components, a field experimentation component and a numerical analysis component. Field experimentation investigates two systems: (1) an electrical heated pavement system with a photovoltaic energy system as its power source, and (2) a hydronic heated pavement system with a solar water-heating system as its heating source. The systems operate under an automated thermostat heating sequence for operation optimization and energy conservation. Study results found the solar systems capable of supplying enough energy to maintain pavement surface temperature above …
Early Life Flexural Performance And Behavior Of Reinforced Bcsa Concrete Beams, Gabriel Cook
Early Life Flexural Performance And Behavior Of Reinforced Bcsa Concrete Beams, Gabriel Cook
Graduate Theses and Dissertations
Belitic calcium sulfoaluminate cement (BCSA) is a hydraulic, rapid setting alternative to ordinary portland cement (OPC) with reduced energy demands and CO2 emissions. BCSA cement has numerous current and potential applications including transportation repair and precast manufacturing. Currently, limited research exists regarding the structural performance of CSA cements, restricting its potential implementation. Thus, the purpose of this research is to provide insight into the flexural performance and behavior of reinforced BCSA concrete beams. Overall, BCSA concrete had similar cracking and loading behavior to the OPC beams, with increased moment capacity for compression controlled specimens. Furthermore, BCSA concrete showed increased tensile …
Service Learning Through Extracurricular Activities: Development And Implementation Of A Transportation Engineering Learning Module, Karla Diaz Corro
Service Learning Through Extracurricular Activities: Development And Implementation Of A Transportation Engineering Learning Module, Karla Diaz Corro
Civil Engineering Undergraduate Honors Theses
This project developed an easy to implement, low-cost learning module. The module has students compare and contrast the challenges of gathering comprehensive and quality transportation data through advanced technologies and traditional approaches while introducing traffic engineering topics like traffic signal timing. The modules target middle through high school students and first and second year undergraduate engineering students. The learning modules introduce transportation engineering using an engaging open-source computer simulation game adapted by students at the University of Arkansas, as part of a capstone project. The activities in the learning modules require off-the shelf, low-cost computer hardware, making it easy for …
Barge Prioritization, Assignment, And Scheduling During Inland Waterway Disruption Responses, Liliana Delgado-Hidalgo
Barge Prioritization, Assignment, And Scheduling During Inland Waterway Disruption Responses, Liliana Delgado-Hidalgo
Graduate Theses and Dissertations
Inland waterways face natural and man-made disruptions that may affect navigation and infrastructure operations leading to barge traffic disruptions and economic losses. This dissertation investigates inland waterway disruption responses to intelligently redirect disrupted barges to inland terminals and prioritize offloading while minimizing total cargo value loss. This problem is known in the literature as the cargo prioritization and terminal allocation problem (CPTAP). A previous study formulated the CPTAP as a non-linear integer programming (NLIP) model solved with a genetic algorithm (GA) approach. This dissertation contributes three new and improved approaches to solve the CPTAP.
The first approach is a decomposition …
Essays On Applications Of Transportation Network Design And Optimization, Amirali Ghaharikermani
Essays On Applications Of Transportation Network Design And Optimization, Amirali Ghaharikermani
Graduate Theses and Dissertations
In this dissertation, we address different transportation problems. The three main outcomes are: designing a battery swap station network, studying gaps in Empty Container Management literature, designing a model with similar characteristics to the vehicle routing problem as well as implementation scenario for it to be applied for a real-world case.
For the designed battery swap station, a model is developed for customer demand satisfaction that permits construction of different types of BSS in the planning network. Our solution methodology is a Tabu Search algorithm combined with a dynamic programming initialization. Numerous tests showed that the proposed TS approach provides …
On The Fatigue Of Headed Shear Studs In Steel-Concrete Composite Bridge Girders, Brianna Laurene Ovuoba
On The Fatigue Of Headed Shear Studs In Steel-Concrete Composite Bridge Girders, Brianna Laurene Ovuoba
Graduate Theses and Dissertations
Shear connectors are commonly used in steel bridges to join the concrete deck and steel superstructure, providing a mechanism for shear transfer across the steel-concrete interface. The most common shear connector is the headed shear stud. In the current AASHTO LRFD Bridge Specifications on composite design, shear stud fatigue often governs over static strength, and a large number of shear connectors often result. This dissertation investigates headed shear stud fatigue capacities and demands, and provides insight into conservancies in existing design specifications through examination of existing high-traffic bridge performance.
To investigate stud capacity, a total of six high-cycle fatigue tests …
Using Historic Pavement Performance Data To Identify And Select Sites For Asphalt Mixture Design Studies, Allyson Richey
Using Historic Pavement Performance Data To Identify And Select Sites For Asphalt Mixture Design Studies, Allyson Richey
Civil Engineering Undergraduate Honors Theses
Since 1997 Arkansas asphalt mixtures have been designed using a procedure commonly known as ‘Superpave’. In a traditional Superpave mix design, the design considers only traditional volumetric parameters; however, recent advances in mix design technology emphasize mixture’s ability to perform in its environment. There are numerous factors which affect the performance characteristics of an asphalt mix. Certainly, the asphalt binder’s performance is a critical variable in this system. Asphalt binders are sensitive to temperature, so much so that their primary parameter on which they are recommended is a function of both temperature and the geographic latitude in which the pavement …
Methodologies For Solving Integrated Transportation And Scheduling Problems, Fereydoun Adbesh
Methodologies For Solving Integrated Transportation And Scheduling Problems, Fereydoun Adbesh
Graduate Theses and Dissertations
This research proposes novel solution techniques to optimize two real-world problems in the area of scheduling and transportation. We first consider a model for optimizing the operations of dredges. In this problem, scheduling and assignment decisions are integrated across a finite planning horizon. Additional constraints and problem elements explicitly considered include, but are not limited, to environmental work window restrictions, budget limitations, dredge operation rates and schedule-dependent dredge availability. Our approach makes use of Constraint Programming (CP) to obtain quality and robust solutions within an amount of time small enough to be useful to practitioners. The expanded feature set of …
Mitigation And Evaluation Of Alkali-Silica Reaction (Asr) And Freezing And Thawing In Concrete Transportation Structures, Richard Albert Deschenes Jr.
Mitigation And Evaluation Of Alkali-Silica Reaction (Asr) And Freezing And Thawing In Concrete Transportation Structures, Richard Albert Deschenes Jr.
Graduate Theses and Dissertations
An evaluation of alkali-silica reaction (ASR) and freezing and thawing (F/T) in concrete transportation structures is presented along with mitigation methods for slowing the rate of deterioration in concrete. A combination of field and laboratory testing confirms ASR deterioration is exacerbated by exposure to F/T. Laboratory testing indicates an aggregate previously deemed inert to ASR, caused ASR deterioration in several concrete pavement and transportation structures. Existing standard test methods deem this aggregate safe for use in concrete. A modified test method shows the concrete can deteriorate rapidly when subjected to cycles of conditions promoting ASR and F/T. Several structures containing …
Optimization Of Concrete Mixtures For Use In Structural Elements, Waleed Almutairi
Optimization Of Concrete Mixtures For Use In Structural Elements, Waleed Almutairi
Graduate Theses and Dissertations
Portland cement is an essential ingredient in concrete. The use of cement is to enhance the strength as well as other hardened properties of concrete mixtures. Determining the accurate amount of cement is important because the required strength may not be achieved if not enough cement is used. By contrast, when using too much cement, concrete cracking may occur that leads to reducing durability. Researchers at the University of Arkansas (UA) have shown that many bridge decks achieve their 28 day design strength of 4000 psi by 7 days of age. Bridge decks having high strength may experience cracking, which …
Essays In Measuring, Controlling, And Coordinating Supply Chain Inventory And Transportation Operations, Payam Parsa
Essays In Measuring, Controlling, And Coordinating Supply Chain Inventory And Transportation Operations, Payam Parsa
Graduate Theses and Dissertations
Supply chain collaboration programs, such as continuous replenishment program (CRP), is among the most popular supply chain management practices. CRP is an arrangement between two partners in a supply chain to share information on a regular basis for lowering logistics costs while maintaining or increasing service levels. CRP shifts the replenishment responsibility to the upstream partner to avoid the bullwhip effect across the supply chain. This dissertation aims to quantify, measure, and expand the benefits of CRP for the purpose of reducing logistics cost and improving customer service. The developed models in this dissertation are all applied in different case …
Decision Support System For Container Port Selection Using Multiple-Objective Decision Analysis, Rivelino De Icaza
Decision Support System For Container Port Selection Using Multiple-Objective Decision Analysis, Rivelino De Icaza
Graduate Theses and Dissertations
Ports are essential for maritime transportation and global supply chains since they are nodes that connect the sea- and land-based modes of transportation. With containerization and supply chains stimulating global trade, ports are challenged to adjust to changes in the market to create value to their customers. Therefore, this dissertation research focuses on the container port selection decision analysis to provide information to help shipping lines select the best port for their shipping networks. Since the problem is complex, dynamic, and involves multiple and conflicting criteria, the research proposes to use the multi-objective decision analysis with Value-Focused Thinking approach. The …
Introduction To Signal Timing & Traffic Control, Sarah V. Hernandez, Mariah Crew, Karla Diaz-Corro, Taslima Akter
Introduction To Signal Timing & Traffic Control, Sarah V. Hernandez, Mariah Crew, Karla Diaz-Corro, Taslima Akter
Civil Engineering Teaching and Learning
The purpose of these lesson plans is to introduce students to traffic signalization basics. Students will be lead through a series of mini-lectures on traffic control and signalization including a discussion on the limitations and benefits of traffic signalization. The lesson plans compliment a computer simulation “game” in which students act as manual operators for a single up to four by four gridded intersection. Students attempt to control the progression of signals to understand the relationship between signal timing and user delay. Through experimentation with the simulation, students generate a presentation discussing the benefits and drawbacks of signal timing and …
Exploring Compaction Effects On Cold In-Place Recycling Mixtures Using Emulsified Asphalt, Erica Ann Yeung
Exploring Compaction Effects On Cold In-Place Recycling Mixtures Using Emulsified Asphalt, Erica Ann Yeung
Graduate Theses and Dissertations
Cold in-place recycling (CIR) is a process that takes three to four inches of existing pavement surface and reuses 100% of it by milling and crushing it, adding asphalt emulsions and/or additives to it, before placing and re-compacting it. There is currently very little research regarding the interaction between the crushed aggregate and asphalt emulsion during the CIR process. In this study, the interactions between the combinations of crushed aggregates and asphalt emulsions were investigated along with select compaction metrics and a raveling performance test. The three types of aggregates included coated limestone, recycled asphalt pavement (RAP), and coated syenite. …
A Quantitative Model For Truck Parking Utilization With Hours Of Service Regulations, Alexis Christine Gaddy
A Quantitative Model For Truck Parking Utilization With Hours Of Service Regulations, Alexis Christine Gaddy
Industrial Engineering Undergraduate Honors Theses
Continual growth in traffic volume on U.S. Highways and insufficient parking for commercial trucking vehicles has led to significant safety concerns for truck drivers. Hours of Service (HOS) regulations dictate driving and rest periods of truck drivers. When a truck driver must stop as designated by the HOS regulations and the nearest parking location is at capacity, the trucker must either continue driving past the HOS limit or park in an undesignated and possibly illegal or unsafe spot such as an off-ramp. The combination of these two variables play an important role in the safety of truck drivers on a …
The Effects Of Aggregate Size On Shear Dynamic Modulus From Torsion Bar, Farida Mahmud
The Effects Of Aggregate Size On Shear Dynamic Modulus From Torsion Bar, Farida Mahmud
Civil Engineering Undergraduate Honors Theses
PavementME Design is based on mechanistic-empirical principles, which take the properties of layer materials into account in predicting pavement responses and performance. Of these principles, dynamic modulus is one of the most important. Dynamic modulus measures strain in response to the applied stress, which mimics loads from traffic and the corresponding deformation of the asphalt pavement. The traditional test for dynamic modulus in the uniaxial configuration cannot be performed on field cores due to lift thickness. Owing to that, the Indirect Tension and torsion bar configuration were developed. This research will focus on the torsion bar, which requires specimens that …
Transportation Engineering: Traffic Control Simulator, Sarah V. Hernandez, Karla Diaz-Corro, Taslima Akter, Magdalena Asborno, Fu Durandal
Transportation Engineering: Traffic Control Simulator, Sarah V. Hernandez, Karla Diaz-Corro, Taslima Akter, Magdalena Asborno, Fu Durandal
Civil Engineering Teaching and Learning
The purpose of these lesson plans is to introduce students to traffic signalization basics. Students will be lead through a series of mini-lectures on traffic control and signalization including a discussion on the limitations and benefits of traffic signalization. The lesson plans compliment a computer simulation “game” in which students act as manual operators for a single up to four by four gridded intersection. Students attempt to control the progression of signals to understand the relationship between signal timing and user delay. Through experimentation with the simulation, students generate a presentation discussing the benefits and drawbacks of signal timing and …
Safety Performance Prediction Of Large-Truck Drivers In The Transportation Industry, Emily Moneka Francis Xavier
Safety Performance Prediction Of Large-Truck Drivers In The Transportation Industry, Emily Moneka Francis Xavier
Graduate Theses and Dissertations
The trucking industry and truck drivers play a key role in the United States commercial transportation sector. Accidents involving large trucks is one such big event that can cause huge problems to the driver, company, customer and other road users causing property damage and loss of life. The objective of this research is to concentrate on an individual transportation company and use their historical data to build models based on statistical and machine learning methods to predict accidents. The focus is to build models that has high accuracy and correctly predicts an accident. Logistic regression and penalized logistic regression models …
Modeling Economic Impacts Of The Inland Waterway Transportation System, Furkan Oztanriseven
Modeling Economic Impacts Of The Inland Waterway Transportation System, Furkan Oztanriseven
Graduate Theses and Dissertations
The inland waterway transportation system of the United States (U.S.) handles 11.7 billion tons of freight annually and connects the heartland of the U.S. with the rest of the world by providing a fuel-efficient and environmentally friendly mode of transportation. This dissertation aims to create decision support tools for maritime stakeholders to measure the economic impacts of the inland waterway transportation systems under real world scenarios including disruptions, demand changes, port expansion decisions, and channel deepening investments. Monte Carlo simulation, system dynamics, discrete-event simulation, agent-based modeling, and multiregional input-output modeling techniques are utilized to analyze the complex relationships between inland …
Analysis Of Bridge Deck Sections By Pseudo-Compressibility Method Based On Fdm And Les: Improving Performance Through Implementation Of Parallel Computing, Blandine Therese Mbianda Kemayou
Analysis Of Bridge Deck Sections By Pseudo-Compressibility Method Based On Fdm And Les: Improving Performance Through Implementation Of Parallel Computing, Blandine Therese Mbianda Kemayou
Graduate Theses and Dissertations
The incidence of wind on bridges produces static and dynamic loading that must be adequately addressed when designing bridges. Dynamic loading is the primary concern, as the amplitude of the structures response to the applied loading may be greatly amplified. Ideally, the bridge's properties should be designed to avoid dynamic loading. Previous investigations of wind loading on bridges consisted of measuring forces produced on scaled models of bridges within wind tunnels. However, these wind tunnel tests are costly and time consuming due to cost to fabricate and instrument the bridge cross sections. Recent advancements in computational power of computers allow …
Exploring The Black Space Of Compressive And Shear Modulus, Airam Marlee Morales Vega
Exploring The Black Space Of Compressive And Shear Modulus, Airam Marlee Morales Vega
Graduate Theses and Dissertations
Uniaxial dynamic modulus is a standard test used to determine the viscoelastic behavior of asphalt pavement materials, with the standard analysis generating a Master Curve. One alternative to the master curve approach is a Black Space diagram, which is a rheological plot that can delineate either dynamic modulus |E*| or shear modulus |G*| vs. phase angle (δ). In this study, four asphalt binders were tested with one aggregate blend. One of these four binders was unmodified and the other three were modified with polymers and acids. Additionally, Polyphosphoric acid (PPA) is compared to the more traditional SBS polymer modification. PPA …
Evaluation Of Poisson’S Ratio Of Asphalt Concrete, Elvis Alexander Castillo Camarena
Evaluation Of Poisson’S Ratio Of Asphalt Concrete, Elvis Alexander Castillo Camarena
Graduate Theses and Dissertations
Poisson´s ratio can be defined as the negative ratio of strains perpendicular to the load direction to the strains parallel to the loading direction. If elastic or viscoelastic models are used, Poisson´s ratio, together with elastic modulus, is a main input used to predict distresses in flexible pavement structures such as rutting and cracking. In asphalt concrete, Poisson’s ratio is commonly measured using two different testing configurations: indirect tension (IDT) and uniaxial. However, results from these two testing configuration can potentially have differences. Design methodologies such as the Mechanistic Empirical Design Guide (MEPDG, now PavementME) have been shown to be …
Measuring Relative Humidity In Concrete Pavements As A Method To Assess Asr Mitigation Measures, Remington G. Reed
Measuring Relative Humidity In Concrete Pavements As A Method To Assess Asr Mitigation Measures, Remington G. Reed
Civil Engineering Undergraduate Honors Theses
Alkali-silica reaction (ASR) in concrete is partly facilitated by available moisture within the concrete. In order to better understand this facilitation and to develop processes for ASR mitigation methods, it is necessary to establish a means of monitoring internal relative humidity (RH) within the concrete. Current procedures for measuring RH are time consuming; requiring several hours of equilibration time and specific external conditions to yield accurate results. In order to better understand RH monitoring, laboratory tests were conducted using commercially available RH probes and different controlled environments. Probes were carefully monitored and calibrated in controlled environments, and laboratory tests on …
Development Of Pre-Stressed Cfrp Fatigue Retrofits For Common Steel Bridge Connections, Korey Albert Pough
Development Of Pre-Stressed Cfrp Fatigue Retrofits For Common Steel Bridge Connections, Korey Albert Pough
Graduate Theses and Dissertations
Aging or deterioration of the nation’s bridge infrastructure is a significant issue that requires attention. Causes for much of this deterioration can be attributed to two main factors, 1) corrosion, and 2) metallic fatigue, both of which work together to reduce the strength and serviceability of bridge components over time. In many instances, strengthening of bridge components using localized retrofits offers an economical and fast solution for increasing the longevity of existing steel bridges; however, such retrofits must be resilient to further corrosion and fatigue damage. In this study, a localized retrofit is developed using pre-stressed Carbon Fiber Reinforced Polymer …
Application Of Polyacrylamide-Based Floc Logs For Turbidity Control At Highway Construction Sites, Kien Ngo
Application Of Polyacrylamide-Based Floc Logs For Turbidity Control At Highway Construction Sites, Kien Ngo
Graduate Theses and Dissertations
Runoff waters generated on highway construction sites can have turbidities in excess of the proposed EPA regulatory standard of 280 NTU due to large areas of exposed soil. The objective of this research was to develop best management practices (BMPs) for the use of anionic polyacrylamide (PAM) based Floc Logs, for turbidity control. Five commercially available types of PAM-based Floc Logs were evaluated in jar tests, using soil excavated from Cato Springs Research Center (CSRC, Fayetteville AR) and six types of clay from the Clay Minerals Society (Chantilly, VA). These results show that no single Floc Log type was suitable …
Alkali Silica Reaction Mitigation Using High Volume Class C Fly Ash, William Joseph Phillips
Alkali Silica Reaction Mitigation Using High Volume Class C Fly Ash, William Joseph Phillips
Graduate Theses and Dissertations
Alkali-Silica Reaction (ASR) is a neutralization reaction that occurs between an acid (silicic acid) and a basic pH pore solution (Calcium Oxide, Potassium Oxide, and Sodium Oxide). ASR causes deleterious expansion within concrete, which can cause durability issues decreasing the life span of concrete. ASR in concrete has been found in increasing quantities since its discovery in 1940 by Stanton. Several cases of ASR have occurred in Arkansas near Fayetteville, Pine Bluff, and Little Rock. The purpose of this research was to develop preventative measures using Class C fly ash in concrete, which contains the moderately reactive aggregates found in …
Development Of Best Management Practices For Turbidity Control During Rainfall Events At Highway Construction Sites Using Polyacrylamide, Joanne Johnson
Development Of Best Management Practices For Turbidity Control During Rainfall Events At Highway Construction Sites Using Polyacrylamide, Joanne Johnson
Graduate Theses and Dissertations
In 2009, the United States Environmental Protection Agency (EPA) promulgated a national turbidity standard for runoff water leaving highway construction sites at 280 nephelometric turbidity units (NTU). Meeting this standard can be challenging as turbidities of runoff waters can exceed 15,000 NTU. The objective of this research was to assess polyacrylamide (PAM), a coagulant aid used in water treatment, to help meet the EPA turbidity regulation. Twelve commercially available PAM types were studied, selected on the basis of charge type (cationic, nonionic, anionic), charge density (0-100%), and molecular weight (0.1-28 Mg mol-1). Jar tests were conducted with runoff waters from …