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Unknown Foundation Determination for Scour

Description: This report describes a project to develop a global approach that would reduce the level of uncertainty associated with unknown foundations.
Date: April 2012
Creator: Briaud, Jean-Louis; Medina-Cetina, Zenon; Hurlebaus, Stefan; Everett, Mark; Tucker, Stacey; Yousefpour, Negin et al.
Partner: UNT Libraries Government Documents Department

Fracture Properties and Fatigue Cracking Resistance of Asphalt Binders

Description: "The main objective of this study was to evaluate the inherent fatigue cracking resistance of asphalt binders in the form of a matrix with rigid particle inclusions. The underlying rational for this approach was to subject the binders to a state of stress that is similar to the one in a full asphalt mixture."
Date: March 2012
Creator: Bhasin, Amit; Izadi, Anoosha & Motamed, Arash
Partner: UNT Libraries Government Documents Department

Megaregion Freight Planning: A Synopsis

Description: "Megaregion interest has grown strongly in the last decade and is now seen be a growing number of planners as offering effective contributions to problems such as modal congestion, development disparity, and air pollution that individual metropolitan areas or cities cannot resolve individually. Megaregion planning presents an alternative way of mitigating metropolitan problems of large-scale transportation systems, green infrastructure, and economic development and has attracted a number of transportation advocates since 2000."
Date: March 2012
Creator: Harrison, Robert; Johnson, Donovan; Loftus-Otway, Lisa; Hutson, Nathan; Seedah, Dan; Zhang, Ming et al.
Partner: UNT Libraries Government Documents Department

Potential Connected Vehicle Applications to Enhance Mobility, Safety, and Environmental Security

Description: "Researchers first conducted a comprehensive review of the state-of-the-art connected-vehicle research and technologies. Once researchers had a thorough understanding of the technology, they focused on selecting and developing the near-term practical applications that use connected vehicle technology. The research team then sought expert opinions from the Texas Transportation Institute working group during two brainstorming sessions, which produced two lists of potential applications and prioritized the applications based on deployment feasibility. In particular, a total of five applications were selected for development of the full concept of operations, including two in safety, two in mobility, and one in environmental security. These applications address various problems, including wrong-way driving and unprotected-grade-crossing crashes (safety): work-zone merge efficiency and safety, and freeway speed harmonization (mobility): and slippery pavement-related crashes (environmental security)."
Date: February 2012
Creator: Balke, Kevin N.; Songchitruksa, Praprut & Zeng, Xiaosi
Partner: UNT Libraries Government Documents Department

Alternative Methods of Flexible Base Compaction Acceptance

Description: "This report summarizes the concerns expressed with the current Texas Department of Transportation(TxDOT) methods, presents approaches some TxDOT districts have taken to overcome problems, and summarizes the current status of other agencies' efforts at mechanistic based acceptance for flexible base. Also this report presents results and findings from a full-scale compaction experiment."
Date: May 2012
Creator: Sebesta, Stephen; Taylor, Ross & Frazier, James
Partner: UNT Libraries Government Documents Department

Positive Feedback: Exploring Current Approaches in Iterative Travel Demand Model Implementation

Description: This report looked at the current Texas Department of Transportation Travel Demand Model (TxDOT TDM) and found that they do not include any impedance or accessibility measures in the trip generation step and found that the best approach is to feed back the output from the traffic assignment step to the trip distribution step.
Date: January 2012
Creator: Reeder, Phillip; Bhat, Chandra & Hall, Kevin
Partner: UNT Libraries Government Documents Department

CAM Mix Design With Local Aggregates

Description: "This study provides revised mix design recommendations for crack attenuating mixtures (CAM) with local aggregates. The use of lower quality aggregates is cost beneficial but limits the application of these mixes in terms of reduced performance. Aggregate guidelines and aggregate quality criteria are provided to enhance the rutting and cracking performance of these mixes. The mix design recommendations as well as aggregate guidelines and quality criteria provided in the report are based on laboratory investigations and field validation is strongly recommended before implementation."
Date: October 2011
Creator: Smit, Andre de Fortier; Prasad, Sivaram; Prozzi, Jorge Alberto & Tahmoressi, Maghsoud
Partner: UNT Libraries Government Documents Department

The Economic Efficiency of Allowing Longer Combination Vehicles in Texas

Description: "This paper shows the economic efficiency of allowing longer combination vehicles in Texas. First, an overview of the truck size and weight policies is explained, with an emphasis on those that affect Texas. Next, LCV operations in other countries are described. Then, an LCV scenario for Texas is chosen, with specific routes and vehicle types. Operational costs for these vehicles are calculated on a cost per mile and cost per ton (or cubic yard) mile. The LCV scenario and the current truck base case are analyzed to find the number of truck trips, the number of mile, and the cost per mile for the chosen routes. These are then compared to estimate the change if LCVs were allowed in Texas."
Date: August 2011
Creator: Walton, C. Michael & Bienkowski, Bridget N.
Partner: UNT Libraries Government Documents Department

Best Practice for Using RAS in HMA

Description: "The use of recycles asphalt shingles (RAS) in hot-mix asphalt (HMA) mixtures has the potential to significantly reduce the cost of asphalt paving mixes while conserving energy and preserving the environment. This report documents the best practices for the use of RAS in HMA in terms of Ras processing, characterizing the processed RAS (binder content,gradations, and performance grad [PG]), RAS mix design, production, and field construction."
Date: October 2011
Creator: Zhou, Fujie; Button, Joe W. & Epps, Jon
Partner: UNT Libraries Government Documents Department

Texas Energy Sector: Past and Future

Description: "The objectives of this research study were to (a) illustrate and quantify the impacts imposed by the energy sector on Texas's transportation system and (b) identify key energy demand indicators by energy source that TxDOT can track in an effort to anticipate the associated future transportation impacts on Texas's transportation system."
Date: December 2011
Creator: Prozzi, Jolanda; Dumais, Ashley; Cline, Mike; Loftus-Otway, Lisa & Seaborne, Eleanor
Partner: UNT Libraries Government Documents Department

Evaluating the effect of street network connectivity on first/last mile transit performance

Description: "This study defines a novel connectivity indicator (CI) to predict transit performance by identifying the role that street network connectivity plays in influencing the service quality of demand responsive feeder transit services."
Date: November 2011
Creator: Chandra, Shailesh. & Quadrifoglio, Luca
Partner: UNT Libraries Government Documents Department

Predicting damage in concrete due to expansive aggregates : modeling to enable sustainable material design

Description: "A poroelastic model is developed that can predict stress and strain distributions and, thus, ostensibly damage likelihood in concrete under freezing conditions caused by aggregates with undesirable combinations of geometry and constitutive properties.Sensitivity of the stress distributions to the aggregate and matrix constitutive parameters are assessed to allow improved concrete design."
Date: April 2012
Creator: Grasley, Zachary Charles & Rahman, Syeda
Partner: UNT Libraries Government Documents Department

Development and validation of a testing protocol for carbon sequestration using a controlled environment

Description: "This project conducted initial testing to develop a method for quantifying plant and soil carbon sequestration capabilities under the controlled conditions of the Texas Transportation Institute's Environmental and Emissions Research Facility (EERF)."
Date: March 2012
Creator: Storey, Beverly B.; Foster, Derrold; Johnson, Jeremy & McFalls, Jett
Partner: UNT Libraries Government Documents Department

Development of warrants for installation of dual right-turn lanes at signalized intersections

Description: "Right-turn lanes provide space for the deceleration and storage of right-turn vehicle, and separate turning vehicles from through movements. Dual right-turn lanes are increasingly used at urban intersections primarily for two reason: (1) to accommodate high right-turn demands and avoid turn-pocket overflows, and/or (2) to prevent right-turn vehicles that exit from a nearby upstream freeway off-ramp (on the left of the roadway) from abruptly changing too many lanes toward the right-turn lane at intersection."
Date: April 2012
Creator: Chen, Xiaoming & Li, Da
Partner: UNT Libraries Government Documents Department

Prioritization of highway maintenance functions using multi-attribute decision making with fuzzy pairwise comparison

Description: "As is the case for most of the Departments of Transportation in the U.S., the Texas Department of Transportation has been experiencing fluctuations of budget for maintaining and preserving its highway infrastructure over the recent years. If the maintenance budget shortfall lasts for an extended period of time, the condition of the highway network would be harmed directly or indirectly since some maintenance work would be deferred or canceled. Thus, in order to control and minimize the risk caused by maintenance budget reductions, it is important for highway agencies to adjust their maintenance and rehabilitation policies to accommodate budget fluctuations. This thesis presents a methodological framework that helps highway agencies quantify the risks to highway networks, and revise the highway routine maintenance work plans to minimize the impact of budget fluctuations. The proposed methodology aims to assist highway agencies in prioritizing and selecting maintenance functions according to the risk of not performing a specific maintenance activity. Also, this methodology considers the subjective nature of decision makers' assessments, allowing different levels of confidence and different attitudes toward risk to be captured as the uncertainty and imprecision involved in the decision making process. In the case study, the proposed methodology is tested with a set of data obtained from the Texas Department of Transportation. The result is compared with the outcome obtained from the crisp Analytical Hierarchy Process using the same set of data. The outcomes from the two methodologies are very close, validating the effectiveness of prioritizing highway maintenance functions using Multi-Attribute Analysis with Fuzzy Pairwise Comparison."
Date: September 2011
Creator: Zhang, Zhanmin & Liu, Wenxing
Partner: UNT Libraries Government Documents Department

Compendium of student papers: 2011 undergraduate transportation scholars program.

Description: "This report is a compilation of research papers written by students participating in the 2011 Undergraduate Transportation Scholars Program. The papers in this compendium report on the following topics, respectively: 1) evaluating the impact of nighttime work zone lighting characteristics n motorists; 2) late night roadway visibility; 3) investigation of the use and pricing of the I-15 express lanes in San Diego; 4) intercity passenger rail access to airports: a case study at the Milwaukee airport; 5) development of a background complexity assessment tool; 6)identifying pavement preservation treatments suitable for performance-related specifications; and 7)arsenic content and retro-reflectivity of glass beads used in pavement markings."
Date: May 2012
Creator: Desorcie, Felicia; Jian, Ruoxin; Kelly, Pete; Larson, Shawn; Rasulo, Marcus; Rivera, Joshua et al.
Partner: UNT Libraries Government Documents Department

Laboratory evaluation of friction loss and compactability of asphalt mixtures

Description: "This study aimed to develop prediction models for friction loss and laboratory compaction of asphalt mixtures. In addition, the study evaluated the effect of compaction level and compaction method of skid resistance and the internal structure of asphalt mixtures."
Date: April 2012
Creator: Kassem, Emad Abdel-Rahman; Masad, Eyad; Awed, Ahmed & Little, Dallas
Partner: UNT Libraries Government Documents Department

Performance measures for metropolitan planning organizations

Description: "The aim of this project is to consolidate available knowledge and provide guidance to transportation agencies, specifically MPOs, to help them incorporate performance measurement relating to transportation planning and operations. This research includes a survey of agency practices and agency needs, development of guidance on effective performance measurement and allied issues of strategic planning, goal setting, and data collection."
Date: April 2012
Creator: Moore, Devin; Ramni, Tara; Norboge, Nicolas & Turnbull, Katherine
Partner: UNT Libraries Government Documents Department