Transportation Engineering Commons^™

Evaluation Of Fracture Principles In Asphalt Concrete Utilizing The Sc(B) Geometry, Airam Marlee Morales Vega

Graduate Theses and Dissertations

Since cracking is one of the principal distresses to be considered in asphalt concrete, multiple fracture tests and geometries have been used to quantify cracking resistance. One of the most popular geometries that have been used in fracture tests is the Semi-Circular bend (SC(B)). However, for this geometry, most of the fracture test methods use different parameters such as thickness, testing temperatures, and loading rates. Thus, the purpose of this research was first to evaluate fracture energy by performing a ruggedness test based on ASTM E1169. Then, to apply fracture mechanics concepts to evaluate three specimen thicknesses (25, 50, and …

An Application Of Bayesian Multilevel Model To Evaluate Variations In Stochastic And Dynamic Transition Of Traffic Conditions, Emmanuel Kidando, Ren Moses, Thobias Sando, Eren Erman Ozguven

Civil and Environmental Engineering Faculty Publications

© 2019, The Author(s). This study seeks to investigate the variations associated with lane lateral locations and days of the week in the stochastic and dynamic transition of traffic regimes (DTTR). In the proposed analysis, hierarchical regression models fitted using Bayesian frameworks were used to calibrate the transition probabilities that describe the DTTR. Datasets of two sites on a freeway facility located in Jacksonville, Florida, were selected for the analysis. The traffic speed thresholds to define traffic regimes were estimated using the Gaussian mixture model (GMM). The GMM revealed that two and three regimes were adequate mixture components for estimating …

Evaluation Of Reducing Cement Content In Ndor Class R Combined Aggregate Gradations, Miras Mamirov, Jiong Hu, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

The main objective of this research project was to achieve a cement reduction on Nebraska slip-form pavement concrete through aggregate particle packing optimization. A literature review was conducted to examine different aggregate optimization tools, quality control tests, and historical data of Nebraska Department of Transportation (NDOT) pavement mixtures. It was found that the Modified Toufar Model has good potential in optimizing particle packing and predicting packing degrees. The combined aggregate void content test was found to be useful to experimentally justify optimized aggregate gradations. The Box Test with a modified index and image analysis tool for surface void estimation was …

Long-Term Performance Evaluation Of Nudeck In Kearney East Bypass, George Morcous, Marc Maguire

Nebraska Department of Transportation: Research Reports

The Kearney East Bypass bridge is the first project that implements the newly developed precast concrete deck system (known as 2nd generation NUDECK). The new system consists of full-depth full-width precast prestressed concrete deck panels that are 12 ft (3.66 m) long each. The panels have covered shear pockets at 4 ft (1.22 m) spacing on each girder line to host clustered shear connectors that are adjustable in height. Narrow unreinforced transverse joints are used to eliminate the need for deck overlay. Also, deck panels are post-tensioned in the longitudinal direction using a new post-tensioning system that eliminates the need …

Standard Design For Nebraska County Bridges, Chungwook Sim, Jiong Hu, Maher K. Tadros, Alexander Bleyhl, David Gee

Nebraska Department of Transportation: Research Reports

Many county-owned bridges in Nebraska need replacement due to their structural deficiency. Most of the bridges needing replacement are in the 40 to 60 ft range. This span range lacks a standard design that fits Nebraska county practices in terms of speed and simplicity of construction. The current systems being used are (a) Precast 1 by 2 ft planks which can span up to 30 ft, (b) Cast-in-place slab bridges which can span up to 50 ft but require extensive field formwork, concrete placing, and curing, and are best when constructed in three-span units, and (c) Inverted tees which can …

Precast Concrete Deck-To-Girder Connection Using Uhpc, George Morcous, Mostafa Abo El-Khier

Nebraska Department of Transportation: Research Reports

The implementation of ultra-high-performance concrete (UHPC) in bridge construction has been growing rapidly in the last two decades due to its excellent mechanical properties, workability, and durability. This report presents a new UHPC connection between precast concrete deck panels and bridge girders that eliminates changes to the design and production of girder shear connectors commonly used in conventional cast-in-place concrete deck construction. In conventional construction, girder shear reinforcement or studs are extended into the cast-in-place concrete deck to transfer interface shear and create composite section. In the new connection, girder shear reinforcement or studs are kept underneath the deck panels, …

Development Of High-Performance Rapid Patching Materials For Pavement Repair, Gholami Shayan, Jiong Hu, Yong-Rak Kim

Nebraska Department of Transportation: Research Reports

Concrete pavements exhibiting severe distresses which require patching are commonly observed in the concrete pavement in Nebraska. Due to the requirements of opening pavement to traffic after placing the rapid patching materials, it is essential for that concrete to achieve high early strength. To ensure this, a high cement content and chloride-based accelerators are currently used in the Nebraska Department of Transportation (NDOT) Portland cement-based rapid-patching materials. Besides its associated high cost, high cement content tends to result in a less stable mix with high shrinkage, high heat of hydration, and high cracking potential. In addition, using chloride-based accelerators has …

Condition Assessment Of Bridge Decks With Asphalt Overlay, Sepehr Pashoutani, Jinying Zhu

Nebraska Department of Transportation: Research Reports

Ground penetrating RADAR (GPR) is a widely used nondestructive testing (NDT) method for bridge deck evaluation. However, the current GPR signal and data processing software and algorithms are not able to provide comprehensive information about bridge deck condition. Although the original objective of this research project was to develop GPR analysis algorithms for condition assessment of bridge decks with asphalt overlay, the scope of work has been expanded to concrete bridge decks with or without overlays.

In this study, the research team developed a complete GPR analysis procedure that includes the following components: 1) obtain zero-time for GPR reflection at …

Fractional Order State Feedback Control For Improved Lateral Stability Of Semi-Autonomous Commercial Heavy Vehicles, Rasheed Mazen Abdulkader

Graduate Theses and Dissertations

With the growing development of autonomous and semi-autonomous large commercial heavy vehicles, the lateral stability control of articulated vehicles have caught the attention of researchers recently. Active vehicle front steering (AFS) can enhance the handling performance and stability of articulated vehicles for an emergency highway maneuver scenario. However, with large vehicles such tractor-trailers, the system becomes more complex to control and there is an increased occurrence of instabilities. This research investigates a new control scheme based on fractional calculus as a technique that ensures lateral stability of articulated large heavy vehicles during evasive highway maneuvering scenarios. The control method is …

Building Along The Railroad: Towns And Tourism In Michigan’S Eastern Upper Peninsula, Bridget Stoetzer

Honors Projects

The state of Michigan is not solely the lower portion or in other words the “mitten.” It is a combination of the lower and upper peninsula. The Upper Peninsula of Michigan (abbreviated the “UP”) is the upper portion of Michigan that is surrounded on three sides by three different Great Lakes: Lake Superior, Lake Michigan, and Lake Huron. It connects to the Lower Peninsula of Michigan by the Mackinac Bridge which crosses five miles across the Straits of Mackinac.

The counties of the Eastern Upper Peninsula are Alger, Chippewa, Luce, Mackinac, and Schoolcraft. They are marked by large stretches of …

Evaluating Urban Downtown One-Way To Two-Way Street Conversion Using Microscopic Traffic Simulation, Bernice Liu

Master's Theses

Located in the heart of Silicon Valley, Downtown San Jose is attracting new residents, visitors, and businesses. Clearly, the mobility of these residents, visitors, and businesses cannot be accommodated by streets that focus on the single-occupancy automobile mode. To increase the potential for individuals to use non-single-occupancy modes of travel, the downtown area must have a cohesive plan to integrate multimodal use and public life. Complete streets are an integral component of the multi-modal transport system and more livable communities. Complete streets refer to roads designed to accommodate multiple modes, users, and activities including walking, cycling, transit, automobile, and nearby …

The Potential For Using Loyalty Rewards And Incentives Programs To Encourage Transit Ridership And Regional Transportation And Land Use Integration, Christopher E. Ferrell

Mineta Transportation Institute

Transit smart cards can be used as a tool for increasing transit ridership, increasing retail sales in transit-oriented developments (TODs) and eventually, increasing opportunities for retail development in TODs. Instead of providing separate loyalty rewards for each store, or chain of stores, such cards would provide loyalty rewards—in several possible forms, including free transit ride credits, cash rewards, retail purchase discounts, sweepstakes rewards—to all transit riders who patronize TOD retail businesses. Additional rewards could also be given to transit riders who live, work, and shop in TODs, and even to riders who take transit for specific shopping trips in TODs. …

The Application Of Gray-Scale Level-Set Method In Segmentation Of Concrete Deck Delamination Using Infrared Images, Chongsheng Cheng, Zhigang Shen

Department of Construction Engineering and Management: Faculty Publications

Conventional nondestructive delamination detection of concrete pavements through thermography is often based on temperature contrasts between delaminated and sound areas. Non-uniform backgrounds caused by the environmental conditions are often challenging for contrast-based methods to robustly differentiate the delaminated areas from the sound areas. Instead of focusing on the temperature contrast, this study proposes a temperature gradient-based level set method (LSM) to detect boundaries for delamination segmentations. A modified edge indicator function is developed to represent the normalized temperature gradient of a thermal image. The experimental study was conducted to evaluate its applicability and stability for boundary detection in terms of …

Evaluation Of The Rheological Behaviors And Molecular Composition Properties Of Crumb Rubber Modified Emulsion For Chip Seal, Md Tanvir Ahmed Sarkar

LSU Master's Theses

An experimental study was conducted to characterize the chemical, molecular, and rheological properties of different asphalt emulsions including a newly introduced tire rubber modified asphalt emulsion. One tire rubber modified asphalt emulsion (CRS-2TR), two conventional emulsions (CRS-2 and CRS-2P), and one asphalt rubber binder (AC20-5TR) were evaluated. The differences in functional groups, chemical composition, and molecular weight distribution of the asphalt binder and emulsions under different aging conditions (Original, RTFO-aged, and PAV-aged) were evaluated by the Saturates, Aromatics, Resins and Asphaltenes (SARA) fractionation test, High-Pressure Gel Permeation Chromatography (HP-GPC), and Fourier Transform Infrared Spectroscopy (FTIR) test, respectively. Superpave Performance Grade …

Application Of Modern, Effective Materials In Rail Road Reinforced Bridge Elements, U.Z. Shermuxamedov, F.Z. Zokirov

Journal of Tashkent Institute of Railway Engineers

The article is about reducing the construction costs of railroad bridges and the effective use modern building materials. The article compares the technical characteristics of composite fittings and metal fittings and their proportionality. Indeed, recourse saving of metal and composite fittings, as well as factors of localization of construction is compared

Mathematical Modeling Of The Structure Cellular Concrete, Anvar Ishanovich Adilkhodjayev, E.V. Shipacheva, S.S. Shaumarov

Journal of Tashkent Institute of Railway Engineers

The article presents the developed mathematical model of the structure of cellular concrete, which allows one to establish pore sizes and characteristics of inter-pore walls corresponding to the required thermal conductivity and strength of the material, and the results of its numerical implementation are presented

Research Of Surface Condition Of The Rails Rollingon Sections Of High-Speed And High-Speed Train Traffic, E.B. Abdualiyev

Journal of Tashkent Institute of Railway Engineers

This article analyzes the intensity of impulse irregularities that occur on the surface of the rolling rail heads on the section of high-speed and high-speed train traffic. On the rolling surface of the rail heads, the formation of pulse irregularities is observed, which are fixed by the measuring system of the track measuring car No. 106. This shows the main character of damage to the surface of the rail head ride

Method Of Calculation Of Self-Stressed Concrete Slabs Supported Along The Contour, S.S. Salixanov

Journal of Tashkent Institute of Railway Engineers

The paper presents the developed method for calculating the contour-supported slab of self-stressed concrete. Reinforced concrete slab on the tension cement replaces the traditional construction of the bridge. In this article, in order to exclude reinforcement, the problem of determining the stress-strain state of self-stressed concrete slabs supported along the contour is considered. The values of stresses in the upper and lower faces of the concrete slab, as well as the bending moment in the middle section of the slab

Construction Features Of Transport Tunnels In The Mountain Areas Of Uzbekistan, M.Х. Miralimov, Sh.U. Normurodov

Journal of Tashkent Institute of Railway Engineers

The paper provides information about the transport tunnel 19,2 km long which was recently completed on new electrified railway line “Angren-Pap” in the mountain area of Uzbekistan. It is noted that the most actual for transport tunnels is account of seismic activity of geological environment in the process of design, construction and maintenance. There are given the effects of earthquakes on underground structures and regularities of displacement and stress distribution in the tunnel linings under seismic impacts. The accumulated experience of earthquake-resistant construction in Uzbekistan shows the need to consider several design schemes for the interaction of tunnels in the …

Research Of System Conditions For Formation Of Failure On Mathematical Models By The Results Of The Research Of Reinforced Concrete Bridges, E.T. Yaxshiev, F.Z. Zokirov, A.B. Karimova

Journal of Tashkent Institute of Railway Engineers

Based on the data of field surveys, the results of assessing the state of reinforced concrete span structures of bridges and characteristic defects that occur in the structure during operation are presented. An analysis of the results of inspections and periodic inspections responsible for the operation of artificial structures shows that a significant part of reinforced concrete spans has various types of defects and damage to load-bearing structures. Studies show that defects have a significant impact on the operational properties of reinforced concrete spans, leading both to a limitation of the speed regime of train movements and to the emergence …