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Noise barriers along high-volume roads reduce traffic noise using either normal-weight materials, such as concrete or brick, or
lightweight materials, such as metal, composites, fiberglass, or acrylic. Although the Virginia Department of Transportation’s
(VDOT) current concrete noise barriers have proven durable, some lightweight metal noise barriers have failed prematurely
because of corrosion, prompting the need to better understand the field performance of lightweight alternatives. This project
aimed to improve the life-cycle management of VDOT’s noise barrier inventory through field evaluations of lightweight
barriers, development of an inspection and asset management framework, and unmanned aerial system (UAS) trial inspections

This guide is designed for State and local officials as well as non-government organizations and advocates who are interested in
partnering with Tribes in their area to improve traffic safety through occupant protection, specifically seat belt use. This guide was
made possible through a collaborative effort that included representatives from Indian Country across the United States, including
Tribes, nations, bands, villages, pueblos, rancherias, as well as State and Federal transportation safety officials and Tribal liaisons.
The guide
• outlines a framework based on asking questions and listening to build understanding and trust between Tribes and the State
and local officials with they will work with;
• provides an overview of sovereignty, Tribal land status, and Indigenous Knowledge and practices and their impact on laws,
enforcement, partnerships, and data; and
• offers suggestions for designing funding mechanisms to better respond to the needs of Tribes.
There are examples and case studies throughout the guide. It also includes an extensive resource section to broaden understanding
of the topics.

The Louisiana Department of Transportation and Development (DOTD) continues to improve its geotechnical data management policies and expand its use of digital data for geotechnical design. New advanced data-rich techniques and methodologies have been developed for geotechnical site characterization, including those recommended by the Advanced Geotechnical Methods in Exploration (A-GaME) program of the Federal Highway Administration (FHWA). Specifically, this research focused on the development and implementation of a web-based platform to efficiently visualize and interpret geotechnical data and help facilitate project delivery. The web-based platform can incorporate geotechnical data from DOTD’s OpenGround dataset, gINT files from consultants, and/or Data Interchange for Geotechnical and Geoenvironmental Specialists (DIGGS) data files for analysis based on the American Association of State Highway Transportation Officials (AASHTO) Section 10 and FHWA Geotechnical Engineering Circular No. 5 (GEC-5) updates.

Virginia and other states face growing shortages of traditional supplementary cementitious materials (SCMs) like fly ash, threatening concrete supply, cost, and VDOT infrastructure performance while hindering efforts to lower cement's global warming potential. To address these supply and sustainability challenges, this study evaluated limestone calcined clay cements (LC3 and LC2) as alternative SCMs, comparing their fresh, mechanical, durability, shrinkage, and environmental properties against VDOT standard Class F coal ash and slag cement.

National RTAP’s Mobility Management in Rural and Tribal Areas technical brief explains the guiding principles, partnership structures, and core competencies that support effective mobility management. It serves as both an educational resource and a practical reference for mobility managers, transit professionals, planners, and decision-makers seeking to design or strengthen coordinated transportation systems.

At seventy, the Interstate Highway System continues to provide significant safety and reliability
benefits, but is deteriorating, experiencing increased congestion as vehicle travel grows quickly, and is
aging rapidly yet there is no adequate plan for its long-term health. While it remains the workhorse of
American travel as the U.S. celebrates its 250th year, the Interstate Highway System is suffering from
severe wear and escalating congestion. To meet future demands, the system urgently requires
sweeping modernization, capacity expansion, and foundational reconstruction.

In 2019, the Transportation Research Board (TRB) provided Congress with a report that found
that the nation’s Interstates are heavily congested and aging, with large portions of the system in need
of major rebuilding and comprehensive upgrades. The report found that addressing the needs of the
Interstate Highway System will require more than a doubling of current investment to adequately
improve the system’s condition, reliability and safety, and that the restoration of the nation’s
Interstate Highway System should be based on a strong collaborative effort between federal leadership
and the states.

TRIP’s America’s Interstate Highway System at 70 report provides the latest information on the
Interstate System, including its benefit in saving lives, time and money, pavement conditions, bridge
conditions, travel trends, traffic congestion levels, truck use, and traffic safety. It reviews the findings
of the TRB Interstate report and concludes with recommended actions - based on the findings of the
TRB report - to ensure that the system can meet the nation’s transportation needs.

Factsheet presenting crash statistics from the Fatality Analysis Reporting System (FARS) and the Crash Report Sampling System (CRSS) focusing on children (persons aged 14 and under).

Precast/prestressed concrete girders with cast-in-place decks are commonly used for bridge construction throughout the United States. However, girder lifespans exceed the lifespans of concrete decks, resulting in the need for deck replacement. This study surveyed United States Department of Transportation (DOT) engineers to determine common deck removal practices. Survey results showed that, although most states have a need to replace bridge decks, few states have comprehensive plans for assessing the long-term effects of deck replacement on girder behavior. This study developed a Python model to estimate girder behavior over its lifespan that accounts for the effects of deck replacement, changes in loading conditions, changes in restraint conditions, and concrete deformations. Time-step analysis was used to calculate incremental changes in girder behavior throughout time, considering several lifespan stages delineated by changes in loading or boundary conditions. The B4 model (Wendner et al., 2013) was used to estimate the creep and shrinkage strain in the concrete. The model was validated against examples in the literature and applied to an example bridge to illustrate function. Modeling results suggest that deck replacement had minimal effect on long-term girder behavior for the bridge considered. A parametric study was also conducted to evaluate the influence of input parameter variations on long-term prestress loss, deflections, and stresses and strains for the example bridge. Parametric study results showed that girder behavior varies widely based on input parameters, suggesting that more research is needed to determine whether other bridge configurations would also be insensitive to deck replacement.

This research focused on the utilization of Light Detection and Ranging (LiDAR) technology within the Louisiana Department of Transportation and Development (DOTD) for various geotechnical applications. The study addressed several key practices, including site investigation and reconnaissance for drilling operations, geotechnical asset management inventory data collection, change detection for forensic evaluations and monitoring, and cross-section data collection for stability analysis. The primary objective of the research was to leverage LiDAR technology to enhance geotechnical infrastructure management within DOTD. The investigation involved a comprehensive analysis of available data within DOTD and other relevant Louisiana agencies. Additionally, the study explored the integration of LiDAR with other data sources and collection technologies, such as drones for local scanning. The research findings contribute to the identification and implementation of LiDAR technology in geotechnical infrastructure, providing valuable insights into its efficacy and potential benefits. By harnessing LiDAR for site investigation and reconnaissance during drilling operations, the study aims to improve the accuracy and efficiency of data collection in challenging terrains. Further, the research explored the role of LiDAR in geotechnical asset management, emphasizing the importance of inventory data collection. Through change detection techniques, LiDAR proves to be a valuable tool for forensic evaluations and continuous monitoring of geotechnical assets, facilitating proactive maintenance and risk mitigation. The study also explores the application of LiDAR in cross-section data collection for stability analysis. By assessing terrain morphology and structural integrity, LiDAR contributes to a more thorough understanding of geotechnical conditions, enabling better informed decision-making for infrastructure stability and resilience. In conclusion, the research underscores the potential of LiDAR implementation in geotechnical applications within DOTD, offering a sustainable and resilient approach to infrastructure management. The insights gained from this study have the potential to enhance DOTD’s capabilities in site investigation, asset management, and stability analysis, ultimately contributing to the longterm sustainability of geotechnical assets.

Ultra-high performance concrete (UHPC) has been used in different applications and was explored to be
used for precast elements; however, there was limited research and guidance on the connection between UHPC
elements. General test methods to evaluate interface strength (e.g., direct tension pulloff, shear pushoff) can be
used with the Mohr-Coulomb Friction Approach to determine the cohesion coefficient and coefficient of friction
typically used to estimate interface shear strength. The test program here sought to explore the bond behavior of
matchcast UHPC with various interface surface conditions, such as surface roughness (including smooth faces
cast on plywood formwork, roughened surfaces created by casting on form liners) and exposed steel fibers at the
interface (created by the use of paste retarders) in order to inform design provisions for matchcast UHPC. The
effect of pre-corroded steel fibers and the surface wetting conditions were considered as well. Trends in interface
shear behavior associated with surface conditions were identified. The most evident outcome from testing was
that the presence of exposed steel fibers provided improved performance relative to only roughened surfaces.
Roughened interfaces can improve the friction of the interface, but the presence of the exposed fibers improved
both cohesive strength and provided improvement to the post-crack tensile strength. Additionally, there was
improved cohesive bonding when prolonged wetting by burlap was made. Extended term ponding had reduced
performance. Cohesion coefficient and friction factors for the various test conditions were assessed. Modification
to interface shear strength provisions to include the effect of wetting conditions on cohesion was presented. The
experimental work provided practical experiences that were translated into considerations for construction.

As the Virginia Department of Transportation (VDOT) transitions from traditional in-pavement sensors to non-intrusive traffic
monitoring technologies, a standardized and mathematically defensible verification process is required to ensure data integrity.
This research establishes a comprehensive Device Acceptance Framework designed to evaluate the volumetric and classification
accuracy of emerging traffic count devices.

The framework was developed through a multi-stage methodology. First, a user needs survey involving VDOT stakeholders
established a 5% error threshold as the primary accuracy target for engineering and planning applications. Second, a robust
operational baseline was established by calibrating existing continuous count stations against absolute, human-verified video
ground truth data.

Third, the established baseline and parameters were integrated into a formal eight-step “fail-fast” protocol. This protocol subjects
candidate devices to progressive evaluations, ranging from simple 24-hour volumetric screenings to rigorous classification tests
under adverse environmental conditions (e.g., heavy rain, dense fog, and snow). A field demonstration of the framework on a
candidate video-based detector illustrated its practical application and the effectiveness of the pass-fail criteria.

The implementation of this framework provides significant operational and financial benefits. By utilizing the pre-calibrated
continuous count station baseline instead of manual video processing, VDOT can achieve a direct cost avoidance of
approximately $321,300 per device certification request. Furthermore, the framework establishes a transparent roadmap for both
the agency and technology vendors, ensuring that only resilient, high-accuracy tools are deployed across Virginia’s traffic
monitoring network. The study recommends developing a standardized traffic count device acceptance procedure, particularly the
“fail-fast” framework to establish a consistent, resource-efficient vetting process for emerging non-intrusive traffic count devices
for VDOT approval.