UNT Libraries Government Documents Department - 20 Matching Results

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Accommodating oversize and overweight loads: technical report

Description: "In this report the research project resulted in a statewide map recommending primary and alternate Oversize/ overweight (OS/OW)route networks for the most common origins and destinations based on historical Motor Carrier Division data. Keeping strategic routes open for OS/OW loads and minimizing the number of reroutes along the way will reduce the impedance and unknowns in this critical segment of the motor carrier industry."
Date: July 2012
Creator: Middleton, Daniel R.; Li, Yingfeng; Le, Jerry & Koncz, Nicholas

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.

Comprehensive evaluation of compaction of asphalt pavements and development of compaction monitoring system

Description: "This report aimed to conduct a comprehensive evaluation of compaction of asphalt pavements and develop software for monitoring field compaction in real time.The results were used to determine the effects of compaction temperature, compaction method, mixture design, and base type on the compactability of asphalt mixtures.Also in this report researchers developed a system for monitoring and documenting the compaction process of asphalt mixtures called compaction monitoring system (CMS)."
Date: April 2012
Creator: Kassem, Emad Abdel-Rahman, 1979-; Scullion, Tom; Masad, Eyad; Chowdhury, Arif; Liu, Wenting; Estakhri, Cindy K. et al.

Development of Texas Transportation Institute's asphalt compaction monitoring system

Description: "In recent years, the Texas Department of Transportation has made significant progress with the development and implementation of new technologies to measure the uniformity of new hot mix asphalt layer construction. In Project 0-6992, researchers took this check one step further by developing an accurate global positioning system tracking system for compaction rolling so that the compaction effort applied can be monitored for 100 percent of the new surface. This report presents details of the hardware and software developed in this study. The system was field tested on a number of new overlay projects in Texas."
Date: July 2012
Creator: Liu, Wenting; Scullion, Thomas & Kassem, Emad

Energy developments and the transportation infrastructure in Texas

Description: "This report describes the work completed to measure the impact of increased level of energy-related activities on the Texas Department of Transportation (TxDOT) right-of-way and infrastructure, as well as develop recommendations to reduce and manage TxDOT's exposure and risk resulting from those activities."
Date: March 2012
Creator: Quiroga, CeĢsar A.; Fernando, E. G. & Oh, Jeongho

Evaluation of traffic control devices : year 3

Description: This project was established to provide a means of conducting small-scale research activities on an as-needed basis so that the results could be available within months of starting the specific research. This report summarizes the research activities that were conducted between September 2010 and August 2011. There were five primary activities and five secondary activities. The five primary activities were evaluating nighttime visibility along rural highways with bright signs, continuing the evaluation of lead-free thermoplastic pavement markings, evaluating contrast pavement marking layouts, continuing the evaluation of accelerated pavement marking test decks, and providing district support for hurricane evacuation routing. In addition, the researchers also started to evaluated criteria for setting 80 mph and 85 mph speed limits, evaluated bridge clearance signing, narrowed the focus of a rotational sign sheeting study, provided technical support for the Texas Manual on Uniform Traffic Control Devices (MUTCD), and provided technical support for the Texas Department of Transportation (TxDOT) sign sheeting specification.
Date: March 2012
Creator: Carlson, Paul J.; Pike, Adam M.; Miles, Jeff D.; Ullman, Brooke R. & Borchardt, Darrel W.

Full-depth reclamation : new test procedures and recommended updates to specifications

Description: Rehabilitating an old pavement by pulverizing and stabilizing the existing pavement is a process referred to as Full Depth Reclamation (FDR). The stabilized layer becomes either the base or sub-base of the new pavement structure. This process has been used widely for over 20 years in Texas to strengthen and widen structurally inadequate pavement sections. This project developed guidelines on successful FDR practices, developed training materials, and identified areas where improvements to current practices are required. To improve the FDR process, this report includes the following enhancements: (1) As current laboratory testing to select the optimal type and amount of stabilizer takes too long and requires too much material, continue to run parallel testing with the small sample test protocols proposed in this report; (2) Use the falling weight deflectometer (FWD) during construction to validate that the design assumptions are being met; (3) Implement the proposed bond test to select the optimum prime material and amount needed to effectively bond the base to the surfacing materials; (4) Modify the specifications to avoid working in freezing conditions; and (5) Consider implementing the other modifications to specifications proposed in this report.
Date: July 2012
Creator: Scullion, Thomas; Sebesta, Stephen; Estakhri, Cindy K.; Harris, Pat; Shon, Chang-Seon; Harvey, Omar et al.

Identification of priority rail projects for Texas: initial methodology/user manual and guidebook

Description: "This project developed a system of evaluative tools for the Texas Department of Transportation (TxDOT) to prioritize its investments in rail-related projects on a statewide basis. This work is meant to ensure that the limited available funding for rail projects is applied in the most beneficial and efficient manner and is focused upon addressing TxDOT's strategic goals. From the findings, researches recommend a transparent methodology for evaluating proposed rail projects and establishing an initial process through which rail-related investments can periodically be re-evaluated."
Date: February 2012
Creator: Morgan, Curtis Alan

Laboratory and field performance measurements to support the implementation of warm mix asphalt in Texas

Description: An objective of this study was to monitor the performance of more than 10 warm mix asphalt (WMA) projects in the state. Several WMA technologies were included in the study (foaming, Advera, Evotherm, Rediset, Sasobit) and it was determined that performance of the warm mix was comparable to hot mix. In addition, mix from two warm mix projects were subjected to different curing times and temperatures and then evaluated for mixture volumetrics and performance properties. Results from this study lend support to the current procedures the Texas Department of Transportation has adopted.
Date: July 2012
Creator: Estakhri, Cindy K.

The overlay tester : a sensitivity study to improve repeatability and minimize variability in the test results

Description: "This report presents a comprehensive sensitivity evaluation of the critical steps of the Overlay Tester (OT) test procedure in an attempt to optimize the OT repeatability and minimize variability in the test results."
Date: February 2012
Creator: Walubita, Lubinda F.; Faruk, Abu N.; Das, Gautam; Tanvir, Hossain A.; Zhang, Jun & Scullion, Tom

Performance comparison of various seal coat grades used in Texas

Description: This report documents research efforts to provide comparative quantitative performance information for various grades of seal coat aggregate available in the Texas Department of Transportation standard specifications. Length of service before replacement and level of noise generated at the tire-pavement interface were the primary focuses of the relative performance evaluations. The additional service life possible from seal coats with larger aggregate and higher asphalt application rates is compared to the additional cost generally associated with these larger aggregate seal coats. The comparative performance information combined with knowledge gathered from numerous department field engineers resulted in the development of guidelines for optimal seal coat grade selection.
Date: July 2012
Creator: Krugler, Paul E.; Wirth, John E.; Estakhri, Cindy K.; Freeman, Thomas J.; Wikander, John P. & Wimsatt, Andrew J.

Performance monitoring pavements with thermal segregation in Texas

Description: This report investigated the performance of asphalt surface mixtures that exhibited thermal segregation during construction from 2004 to 2009. The results do not show that thermally segregated locations will fail within three to seven years but they do show that instances of thermal segregation may continue to be anomalous locations in the layer that could lead to failures in the pavement structure.
Date: April 2012
Creator: Sebesta, Stephen & Scullion, Tom

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.

Research and recommendations for a statewide sign retroreflectivity maintenance program

Description: "This report evaluated Texas Department of Transportation's (TxDOT) current sign retroreflectivity maintenance practices, assessed their effectiveness, and recommended statewide sign retroreflectivity maintenance practices that could be easily and effectively implemented to ensure that TxDOT would be in compliance with the new Manual on Uniform Traffic Control Devices (MUTCD) language related to minimum sign retroreflectivity."
Date: April 2012
Creator: Carlson, Paul J.; Higgins, Laura L. & Re, Jonathan M.

TxDOT uses of real-time commercial traffic data : opportunity matrix

Description: Based on a TxDOT survey, a review of other state DOTs, and researcher understanding of Intelligent Transportation System (ITS) needs, the Texas Transportation Institute (TTI) team developed a comprehensive list of opportunities for TxDOT to consider pertaining to future use of private sector (PS) data. Specific opportunities for applying private data were reviewed in light of accuracy of the data, coverage areas, data availability, cost, and control of the data stream.
Date: January 2012
Creator: Middleton, Dan; Brydia, Robert; Kraus, Edgar; Cheu, Kelvin; Rajbhandari, Rajat, 1973-; Songchitruksa, Praprut et al.