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    <title>Transport Research International Documentation (TRID)</title>
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    <atom:link href="https://trid.trb.org/Record/RSS?s=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" rel="self" type="application/rss+xml" />
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    <copyright>Copyright © 2026. National Academy of Sciences. All rights reserved.</copyright>
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    <managingEditor>tris-trb@nas.edu (Bill McLeod)</managingEditor>
    <webMaster>tris-trb@nas.edu (Bill McLeod)</webMaster>
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      <title>Transport Research International Documentation (TRID)</title>
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      <link>https://trid.trb.org/</link>
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      <title>Connected Vehicle Pilot Deployment Program Independent Evaluation: Data Plan – New York City</title>
      <link>https://trid.trb.org/View/1984256</link>
      <description><![CDATA[This report describes the data management plan that the Texas Transportation Institute (TTI) Connected Vehicle Pilot Deployment (CVPD) Evaluation Team, as the Independent Evaluator, plans to follow in conducting its evaluation of the New York City CVPD. This plan describes the data that the TTI CVPD Evaluation Team plans to use to identify operational scenarios to be examined in the analysis, conduct the mobility, environmental, and public agency efficiency evaluation, and calibrate the simulation models used in the analysis. The plan also provides the approach that the TTI CVPD Evaluation Team plans to use to maintain privacy in the data it collects. The plan also highlights the step that the TTI CVPD Evaluation Team is using to maintain the quality of the data it collects. This plan also describes how the TTI CVPD Evaluation Team use and upload data to the Security Data Commons.]]></description>
      <pubDate>Mon, 27 Jun 2022 08:59:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/1984256</guid>
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    <item>
      <title>The Effectiveness of Using the Overlay Tester Setup to Evaluate the Performance of Asphalt Mixtures against Reflective Cracking</title>
      <link>https://trid.trb.org/View/1763328</link>
      <description><![CDATA[Reflective cracking is common distress when hot-mix asphalt (HMA) overlays are constructed on top of a pre-cracked base. Cracks on existing base gradually propagate upward because of traffic loading and/or temperature variation, reach surface course, and result in reflective cracking. Previous studies demonstrated that Texas Transportation Institute overlay tester (OT) could effectively simulate the effect of temperature variation, which is considered as the leading mechanism causing reflective cracking in the field. In this study, the effectiveness of using the OT test setup to mimic the field and evaluate the performance of various HMAs against reflective cracking is assessed based on various aspects found in the literature. It was concluded that OT is the most suitable equipment to study thermally induced reflective cracking in the laboratory. Additionally, potential modifications to improve the OT setup is proposed, which is expected to provide a more representative performance evaluation of mixtures against reflective cracking.]]></description>
      <pubDate>Wed, 27 Jan 2021 10:10:44 GMT</pubDate>
      <guid>https://trid.trb.org/View/1763328</guid>
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      <title>Development of a New Manual for Assessing Safety Hardware TL-3 Low-Profile Portable Concrete Barrier for High-Speed Applications</title>
      <link>https://trid.trb.org/View/1597745</link>
      <description><![CDATA[A sight-distance problem is associated with use of 32-in. tall concrete longitudinal barriers, specifically in certain work zone locations and at nighttime. These 32-in. tall barriers can obstruct drivers’ eyesight, making it difficult for drivers to detect oncoming vehicles on the other side of these barriers. To address this sight-distance problem while protecting the errant vehicles, researchers at the Texas Transportation Institute (TTI) developed a 20-in. tall low-profile portable concrete barrier (PCB) for use in low-speed work zones in the early 1990s. To address the problem for high-speed application, TTI researchers applied modifications to the 20-in. tall low-profile PCB. Researchers designed two retrofit metal rail systems to be added on top of the existing 20-in. tall low-profile PCB to address roadside and median applications. The systems successfully performed in full-scale crash testing according to NCHRP Report 350 Test Level (TL) 3 evaluation criteria. This paper describes the efforts to develop and evaluate the crashworthiness of a new low-profile PCB design for high-speed applications. The crash tests were performed following Manual for Assessing Safety Hardware (MASH) guidelines and evaluation criteria. Based on results from finite element computer simulations performed to aid design, MASH full-scale crash tests were conducted on a low-profile PCB system comprised of 26-in. tall, 30-ft long barrier segments, with a T-shaped profile. Based on constructability feedback, the sides of the barrier were formed with a negative 1:18 slope, which allows for ease of construction forming. The new low-profile PCB performed acceptably as a MASH TL-3 longitudinal barrier.]]></description>
      <pubDate>Mon, 13 May 2019 12:12:19 GMT</pubDate>
      <guid>https://trid.trb.org/View/1597745</guid>
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    <item>
      <title>Does compact development increase or reduce traffic congestion?</title>
      <link>https://trid.trb.org/View/1491003</link>
      <description><![CDATA[From years of research, we know that compact development that is dense, diverse, well-designed, etc. produces fewer vehicle miles traveled (VMT) than sprawling development. But compact development also concentrates origins and destinations. No one has yet determined, using credible urban form metrics and credible congestion data, the net effect of these countervailing forces on area-wide congestion. Using compactness/sprawl metrics developed for the National Institutes of Health, and congestion data from the Texas Transportation Institute's (TTI's) Urban Mobility Scorecard Annual Report database, this study seeks to determine which opposing point of view of sprawl and congestion is correct. It does so by (1) measuring compactness, congestion, and control variables using the best national data available for U.S. urbanized areas and (2) relating these variables to one another using multivariate methods to determine whether compactness is positively or negatively related to congestion. The authors' model (and earlier studies by the same authors) suggests that an increase in compactness reduces the amount of driving people do, but also concentrates the driving in smaller areas. The former effect is slightly larger than the latter. The relationship between compactness and congestion falls short of statistical significance at the conventional 0.05 level. This analysis does not support the idea that sprawl acts as a “traffic safety valve,” as some have claimed. However, it also does not support the reverse idea that compact development offers a one-stop solution to congestion, as others have claimed. Developing in a more compact manner may help at the margin, but the greatest reduction in congestion appears to be achievable through expansion of surface streets and higher highway user fees.]]></description>
      <pubDate>Fri, 29 Dec 2017 09:35:20 GMT</pubDate>
      <guid>https://trid.trb.org/View/1491003</guid>
    </item>
    <item>
      <title>New Mechanistic Tool Assesses Joint Sealant Effectiveness</title>
      <link>https://trid.trb.org/View/1427322</link>
      <description><![CDATA[Allowing assessment of the sealant effectiveness on pavement performance, a new mechanistic tool for analysis of specific combinations of traffic, climate, base materials and sealant condition on subbase erosion and pavement performance is the first tool of its kind. Results of a study from the Texas Transportation Institute (TTI) entitled, "Qualification of Joint Sealant Effectiveness Regarding Jointed Concrete Pavement Performance" have been released, in which a more rigorous approach to evaluating performance in terms of the amount of infiltration through the joint and the consequential impacts on subbase erosion and pavement was undertaken. A discussion of the report is presented in this article.]]></description>
      <pubDate>Tue, 25 Oct 2016 09:59:07 GMT</pubDate>
      <guid>https://trid.trb.org/View/1427322</guid>
    </item>
    <item>
      <title>A MASH TL-3 Compliant Short Radius System</title>
      <link>https://trid.trb.org/View/1394550</link>
      <description><![CDATA[It is difficult if not physically unattainable to provide the required length of need barrier along a highway if it intersects private driveways and county roads. The presence of site constraints such as a bridge rail or a culvert along the highway may not allow the placement of a properly designed guardrail. In these cases, the alternatives are to relocate the site constraint if possible, shorten the guardrail length, or provide a curved guardrail design. The curved guardrail design is known as short radius or T-intersection depending on specifics of such constraints. Researchers and practitioners in the roadside safety area have been investigating the short radius issue. Subsequently, investigators conducted numerous crash tests for different short radius guardrail designs. None of those designs passed National Cooperative Highway Research Program (NCHRP) Report 350 TL-3 criteria (1). In 2009, the crash testing guidelines have been updated to the Manual for Assessing Safety Hardware (MASH) s (2). MASH increases the impact severity for TL-3 tests. Satisfying such impact severity became even more challenging for any short radius system. This paper presents a MASH TL-3 compliant short radius design that was successfully crash tested using impact conditions adopted from the crash cushion test matrix. Texas A&M Transportation (TTI) researchers used nonlinear finite element simulation to identify the performance of several design concepts. Then, the research team simulated the most promising design concept with refined modeling to finalize the design of the proposed short radius system. TTI staff constructed and tested successfully this short radius system per MASH TL-3 Tests conditions, namely tests 3-33, 3-32, 3-31 and 3-35.]]></description>
      <pubDate>Mon, 29 Feb 2016 16:57:11 GMT</pubDate>
      <guid>https://trid.trb.org/View/1394550</guid>
    </item>
    <item>
      <title>Root-Zone Amendments for Highway Right-of-Way Tree Plantings: A Demonstration Project</title>
      <link>https://trid.trb.org/View/1377106</link>
      <description><![CDATA[The Texas Department of Transportation (TxDOT) and the Texas Transportation Institute’s (TTI)  Environmental Management Program work with TxDOT Districts to develop roadside management practices that  mitigate the highway right-of-way environment and promote healthier, more rapid plant establishment.  This research  study compared the effects of different root-zone soil amendments on tree establishment and growth within the  highway right-of-way environment. The demonstration project site was selected at the intersection of Interstate  Highway (IH) 27 at Business IH 27 in Plainview, Texas.  The funding for the project was from TxDOT’s Construction  Landscape Program with a design budget of $185,000.  Project installation was in the spring of 1996. Results show  that the majority of the trees receiving the treatment consisting of mycorrhizal inoculation, acrylamide copolymer, dry  soluble yucca plant extract, soluble sea kelp extract, and humic acid had a positive response compared to the control  groups and other treatment types. However, the treatment types are species specific in their overall effectiveness.  Further research addressing the issues of a larger sampling of trees, more effective identification methods, and a  concerted maintenance program for the demonstration site should be examined prior to making any  recommendations for field application.]]></description>
      <pubDate>Wed, 23 Dec 2015 08:08:27 GMT</pubDate>
      <guid>https://trid.trb.org/View/1377106</guid>
    </item>
    <item>
      <title>The 8-year reach: TxDOT taps academia for advanced comm system</title>
      <link>https://trid.trb.org/View/1367913</link>
      <description><![CDATA[The Texas Department of Transportation (TxDOT) started a $2 billion reconstruction of I-35 in central Texas in 2010, estimated to take years to complete. The challenges it would face included the need to minimize construction impacts to travelers and businesses and landowners adjacent, as well as providing real-time traffic information to road users in order to allow them to make informed travel choices. The Texas A&M Transportation Institute (TTI) assisted by conducting research to help meet those challenges, which resulted in an advanced traveler information system to keep the public informed during the multiple years of construction, as well as enhance safety and facility mobility. Details of the information system are shared here.]]></description>
      <pubDate>Fri, 25 Sep 2015 16:28:33 GMT</pubDate>
      <guid>https://trid.trb.org/View/1367913</guid>
    </item>
    <item>
      <title>Connected Vehicle Test Bed at the Riverside Campus</title>
      <link>https://trid.trb.org/View/1341974</link>
      <description><![CDATA[The Texas A&M Transportation Institute (TTI) shares an industry vision where no vehicles collide and users can interact with automated and connected transportation to transform how people live, work, and interact with our environment. Connected transportation has the potential to enhance the safety of the transportation system by expanding that vision to include communication between the transportation infrastructure and various modes of transportation. In this project, TTI researchers developed a framework and a Concept of Operations to design and operate an automated and connected vehicle test bed in the Riverside Campus. The researchers were also engaged in discussion with external agencies, other researchers, and private industry to understand their needs for a test bed and how TTI can leverage it to bring in additional research. The researchers acquired and tested technology components to understand how vehicles equipped with Dedicated Short Range Communication (DSRC) technology interact with roadside infrastructure. Lessons learned from the test would be valuable to design a test bed in more detail to develop and test automated and connected vehicle applications.]]></description>
      <pubDate>Thu, 26 Feb 2015 09:49:52 GMT</pubDate>
      <guid>https://trid.trb.org/View/1341974</guid>
    </item>
    <item>
      <title>Small aggregate, polymer modifiers key to new Texas thin lift mixes</title>
      <link>https://trid.trb.org/View/1312789</link>
      <description><![CDATA[New pavements are being developed by researchers at the Texas A&M Transportation Institute (TTI) and the Texas Department of Transportation (TDOT) that are much thinner than traditional overlays and are made with high quality stones and polymer modified asphalt that are expected to last longer and require less maintenance. State, county and city officials are eager to use overlay in the hopes of saving money and inconvenience, as well as providing smoother rides. Details of the pavement testing and mixing leading up to its development, as well as its benefits, are presented here.]]></description>
      <pubDate>Fri, 20 Jun 2014 09:20:29 GMT</pubDate>
      <guid>https://trid.trb.org/View/1312789</guid>
    </item>
    <item>
      <title>Greenhouse Gas Emissions and Urban Congestion: Incorporation of Carbon Dioxide Emissions and Associated Fuel Consumption into Texas A&amp;M Transportation Institute Urban Mobility Report</title>
      <link>https://trid.trb.org/View/1288717</link>
      <description><![CDATA[The Texas A&M Transportation Institute’s Urban Mobility Report (UMR) is acknowledged to be the most authoritative source of information about traffic congestion and its possible solutions. As policy makers from the local to national levels devise strategies to reduce greenhouse gas (GHG) emissions, the level of interest in the environmental impact of urban congestion has increased. To this end, the researchers developed and applied a methodology to determine carbon dioxide (CO₂) emissions caused by congestion for inclusion in the UMR. The methodology also estimated fuel consumption on the basis of the CO₂ emissions estimates. The researchers developed a five-step methodology with data from three primary data sources: (a) FHWA’s Highway Performance Monitoring System, (b) INRIX traffic speed data, and (c) the U.S. Environmental Protection Agency’s Motor Vehicle Emissions Simulator model. Results were intuitive and reasonable when emission rates (pounds of CO₂ per mile) were compared with the emissions inventories in selected cities. The researchers incorporated the new methodology for all urban areas into the 2012 UMR and plan to include the same measures in future releases of the report. The researchers reported that, in 2011, 56 billion pounds of additional CO₂ were produced in all 498 urban areas during congestion only; this amount equated to 2.9 billion gallons of wasted fuel. The amount of CO₂ produced under free-flow conditions (i.e., absent congestion) was 1.8 trillion pounds in 2011 in all 498 urban areas.]]></description>
      <pubDate>Fri, 21 Feb 2014 15:18:37 GMT</pubDate>
      <guid>https://trid.trb.org/View/1288717</guid>
    </item>
    <item>
      <title>Measuring Misery</title>
      <link>https://trid.trb.org/View/1257572</link>
      <description><![CDATA[As part of their yearly Urban Mobility Report, the Texas A&M Transportation Institute (TTI) has developed the Planning Time Index (PTI) as a means of gauging the unreliability of a commute. The PTI quantifies the reliability of travel by calculating how much longer a commute may take at a given time compared to that same trip's duration when traffic is low. The PTI varies on different roads around the country. The Urban Mobility report also approximates that 56 billion pounds of carbon dioxide emissions are caused by traffic congestion. The levels of traffic congestion in the United States has remained steady in the past few years, and the Time Travel Index (the difference in duration of commute during rush hour as opposed to during low-traffic times) has stayed at 1.18. The costs of congestion on the roads is high, and much of it can be attributed to wasted time. Researchers say that a variety of techniques are necessary to address congestion across the country, and important facets are traffic management and public transportation.]]></description>
      <pubDate>Fri, 09 Aug 2013 07:20:05 GMT</pubDate>
      <guid>https://trid.trb.org/View/1257572</guid>
    </item>
    <item>
      <title>Creating a New Method to Identify the Worst Bottlenecks in Texas</title>
      <link>https://trid.trb.org/View/1240617</link>
      <description><![CDATA[Since 2009 the Texas Department of Transportation (TxDOT) has posted a list of the most congested roadway sections in the state on its website (1).  This list is produced annually by TxDOT and the Texas Transportation Institute (TTI) using a jointly-developed methodology.  The two agencies have developed an approach that combines traffic speed data from annual archives of private sector data companies, basic roadway geometry, and traffic counts published in the TxDOT statewide roadway inventory file (RHiNo) (2) to calculate congestion-related performance measures.  A set of volume distribution curves, combined with daily traffic counts, is used to estimate 15-minute volumes for each average day of the week.  These estimated 15-minute volumes are combined with 15-minute speed data to calculate delay.  Performance measures such as annual delay per mile, congestion cost, and the Travel Time Index are produced from this analysis and are used to rank the congested segments across Texas.   This paper describes the process used to produce these statistics.]]></description>
      <pubDate>Fri, 15 Mar 2013 09:48:03 GMT</pubDate>
      <guid>https://trid.trb.org/View/1240617</guid>
    </item>
    <item>
      <title>Evaluating Global Freight Corridor Performance for Canada</title>
      <link>https://trid.trb.org/View/1105651</link>
      <description><![CDATA[As part of Transport Canada’s Gateways and Trade Corridors Initiative, the Directorate of Economic Analysis was interested in developing freight performance measurements for goods using Canada’s international gateways and traveling along its freight transportation corridors. These performance indicators—termed “fluidity” measures—will assist Transport Canada in painting a clear picture of system efficiency for its freight-significant corridors. The indicators will ultimately aid Transport Canada in identifying to what extent the government of Canada’s policies and investment in infrastructure are being leveraged and operated to support trade and economic prosperity. Transport Canada contracted with the Texas Transportation Institute (TTI) to develop and apply the indicators for measuring freight system performance. Researchers created two “fluidity indicators” using an index approach. One indicator captures average conditions (Fluidity Index), while the other indicator captures daily variation in travel time (Planning Time Index). Because freight moves according to both travel time and delivery requirement schedules, and because travel time varies according to mode, the performance measures use a normalizing concept to allow comparisons within a mode and across an entire supply chain. This paper describes the development and application of the measures. The paper includes two applications. One application demonstrates how the fluidity measures are computed and presented for truck shipments. In the second application, researchers demonstrate the use of the fluidity measures for monitoring freight system performance for an international and multimodal corridor from China to Canada. The measures, application, and findings documented in this paper are valuable for practitioners and freight movement stakeholders interested in monitoring freight system efficiency.]]></description>
      <pubDate>Wed, 20 Jul 2011 07:27:30 GMT</pubDate>
      <guid>https://trid.trb.org/View/1105651</guid>
    </item>
    <item>
      <title>Promoting Workforce Development for the Transportation Profession through a Multi-University/Agency Partnership</title>
      <link>https://trid.trb.org/View/1102472</link>
      <description><![CDATA[The objective of this multi-university/agency partnership between Prairie View A&M University (PVAMU), Texas Transportation Institute (TTI), and Texas A&M University (TAMU) is to build on the progress made through the University Transportation Center for Mobility (UTCM) seed funding to produce high-quality transportation professionals from underrepresented groups through research and other real-world experiences. This partnership strengthened the existing pipeline between local high schools and PVAMU by attracting bright young minds for a pair of summer program experiences during students’ last two summers before graduation from high school. One program is the existing Summer Transportation Institute (STI) Program, and the second is the STI Scholars program, initiated as part of the previous UTCM project and further developed in this project. The newly developed curriculum for the STI Scholars program is more challenging than the STI experience; Scholars get a chance to mentor new STI participants and also gain invaluable experience working with transportation professionals at TTI. As part of the program, STI Scholars are encouraged to pursue an existing four-year civil engineering program at PVAMU. The project produced a network of (i) former students, (ii) educational professionals (counselors and teachers), and (iii) public and private agencies including academia to ensure long-term sustainability of the program. This program can serve as a model for other outreach programs at other locations across the nation.]]></description>
      <pubDate>Tue, 17 May 2011 08:50:35 GMT</pubDate>
      <guid>https://trid.trb.org/View/1102472</guid>
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