UNT Libraries Government Documents Department - 87 Matching Results

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Operational Performance Management of Priced Facilities

Description: This study provides a framework in which operating decisions for priced facilities can be made and can guide the changes in operational strategies for a facility over time. The research process was initiated with a literature review and targeted interviews of toll and managed lane operators to assess the state of the practice in performance measurement for pricing and other operational changes. The research team then developed guiding principles for identification, selection, and communication of performance measures and targets. A conceptual framework was formulated and data collection infrastructure needs were also documented. The conceptual framework was then developed into a more detailed version in a web-based format. This report documents the research findings and results and provides guidance on the use of the web-based framework tool. In addition, several outreach products were developed under this study to assist agencies in communication of performance management principles for proactive management of priced facilities.
Date: March 2011
Creator: Goodin, Ginger; Burris, Mark; Lomax, Timothy J.; Geiselbrecht, Tina & Brydia, Robert

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

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

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.

Development of the Transportation Revenue Estimator and Needs Determination System (TRENDS) forecasting model: MPO sub-models and maintenance

Description: "This report summarizes the technical work performed developing and incorporating Metropolitan Planning Organization sub-models into the existing Texas Revenue Estimator and Needs Determination System (TRENDS) model. Additionally, this report explains the maintenance and monthly updates performed on the TRENDS model."
Date: September 2011
Creator: Glover, Brianne; Norboge, Nicolas. & Ellis, David

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

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.

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.

Manual for Assessing Safety Hardware test 3-11 of the Texas Department of Transportation Portable Concrete Traffic Barriers with sign support assembly

Description: This report presents the details of the design developed for mounting the traffic control sign support on top a portable concrete traffic barrier (PCTB), description of the full scale crash test performed on the design, and an assessment and evaluation of the performance of the PCTB with the sign support mounted on top according to specifications of "Manual for Assessing Safety Hardware" (MASH). The PCTB mounted sign support assembly anchored to the top of the TxDOT Type 2 PCTB tested for this project performed acceptably for MASH test 3-11.
Date: January 2011
Creator: Williams, William F. & Menges, Wanda L.

Safety and economic impacts of converting two-way frontage roads to one-way : methodology and findings

Description: In the research documented here, researchers develop information to communicate the safety and economic impacts of converting frontage roads from two-way to one-way. Researchers studied five locations in Texas where frontage roads were converted from two-way operation to one-way operation. Researchers identified a comparison site in Texas that remained two-way for comparison to four of the treatment (conversion) sites. Researchers developed accident modification factors (AMFs) related to frontage road conversion segments that roadway designers can use to guide frontage road conversion project planning. Researchers developed AMFs based on non-property-damage-only (non-PDO) crashes for segments and interchange intersections. Researchers developed 12 AMFs and provide confidence intervals around the estimates. Researchers describe how the AMFs were developed, associated caveats, and how to apply the AMFs. Researchers also document the process used to build the safety database from electronic data-sets and printed crash reports. Finally, researchers provide recommendations to facilitate and expedite future crash analysis. Researchers attempted to investigate the economic impacts of frontage road conversion by analyzing gross sales data, appraisal data, employment data, and surveys of business owners/managers and customers. Only the appraisal data and survey information were at the parcel level along the corridors and survey sample size was limited.
Date: January 2011
Creator: Eisele, William L.; Yager, Christine E.; Brewer, Marcus A.; Frawley, William E.; Park, Eun Sug; Lord, Dominique et al.

Manual for Assessing Safety Hardware test 3-11 on the Texas T101 bridge rail

Description: The Texas T101 bridge rail is widely used in the state of Texas. Previous testing demonstrated its ability to contain and redirect passenger cars and a 20,000-lb school bus. Based on this testing, the Federal Highway Administration accepted the T101 bridge rail as an NCHRP Report 350 TL-3 barrier. However, its impact performance with pickup trucks was never evaluated. Under research project 0-5526, Impact Performance of Roadside Safety Appurtenances, researchers conducted a performance assessment of Texas roadside safety devices to help evaluate the impact of adopting the new AASHTO Manual for Assessing Safety Hardware (MASH) guidelines on current hardware. Testing and evaluation of the T101 bridge rail was recommended as a high priority. This recommendation was based primarily on the absence of pickup truck testing on the system, and concerns that the 27-inch rail height may not be compatible with pickup trucks and SUVs under design impact conditions. The T101 bridge rail did not meet MASH evaluation criteria for test 3-11. The vehicle overturned after losing contact with the barrier.
Date: March 2011
Creator: Bligh, Roger P. & Menges, Wanda L.

Internal trip capture estimator for mixed-use developments

Description: This report describes a spreadsheet tool for estimating trip generation for mixed-use developments, accounting for internal trip capture. Internal trip capture is the portion of trips generated by a mixed-use development that both begin and end within the development. The importance of internal trip capture is that those trips satisfy a portion of the total development's trip generation and they do so without using the external road system. As a result, a mixed-use development that generates a given number of total trips creates less demand on the external road system than single-use developments generating the same number of trips. This report describes the spreadsheet estimator and how to use it. It describes the data behind the estimator as well as how those data are applied. The two Texas mixed-use developments from which most of the data were derived are also described. This report is supplemented by the Excel® spreadsheet itself as well as task memoranda that document the survey data collected as part of this project.
Date: February 2010
Creator: Bochner, Brian S. & Sperry, Benjamin R.

Highway safety design workshops

Description: Highway safety is an ongoing concern for the Texas Department of Transportation (TxDOT). As part of its proactive commitment to improving highway safety, TxDOT is moving toward including quantitative safety analyses earlier in the project development process. To assist in achieving this goal, TxDOT research project 0-4703 developed the Roadway Safety Design Workbook for engineers responsible for highway geometric design. This Workbook describes quantitative safety relationships for specific design components known to be correlated with crash frequency. As part of TxDOT Project 0-4703, a series of workshops were developed to share safety information with TxDOT roadway designers. Information in the Workbook was used as the basis for the workshops. The workshops addressed rural highways, urban streets, and freeways. They included a mixture of classroom discussion and hands-on training activities for the participants. The participants indicated that the information presented in the workshops will be beneficial as they make decisions about highway safety improvements.
Date: November 2010
Creator: Bonneson, James A. & Pratt, Michael P.

Development of a model performance-based sign sheeting specification based on the evaluation of nighttime traffic signs using legibility and eye-tracker data

Description: "This report focused on the evaluation of traffic sign sheeting performance in terms of meeting the nighttime driver needs. Using the luminance requirements derived from the study and market-weighted headlamp flux matrices, the researchers developed an approach to sigh sheeting specification that is based on nighttime driver needs."
Date: September 2010
Creator: Carlson, Paul J.; Miles, Jeffrey D.; Park, Eun Sug; Young, Sarah; Chrysler, Susan & Clark, Jerremy

Microsurfacing in Texas

Description: This report describes the current state of practice of microsurfacing in Texas and compares it to best practices extracted from existing literature. A survey of DOT personnel, contractors and emulsion suppliers in Texas provides insight into the most crucial factors contributing to the success or failure of a microsurfacing. From the results of the survey, literature reviews, case studies and site visits, the research team analyzed material selection and mix design methods, construction practices, equipment practices and performance measures for microsurfacings.
Date: August 2011
Creator: Broughton, Benjamin & Lee, Soon-Jae

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.

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

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.

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.