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Human trafficking affects hundreds of thousands of minors and adults in the United States through labor and sex trafficking. Organizations such as TAT, Polaris, the Department of Homeland Security Blue Campaign, and state transportation agencies have developed strategies to identify trafficking, assist victims, and reduce demand. Successful efforts often rely on strong partnerships and educating individuals to recognize and report signs of trafficking. Collaboration among agencies, organizations, businesses, and communities is essential to disrupt trafficking networks and ensure that victims are identified, protected, and connected with appropriate services.

NCHRP Research Report 1191: Countering Human Trafficking: A Toolkit for State DOTs, produced by TRB’s National Cooperative Highway Research Program, addresses the role of state departments of transportation in disrupting human trafficking. The toolkit has two primary components: leadership-focused tools and operational-focused tools. The leadership-focused tools are designed to assist administration officials and executives in making key decisions to initiate a program to disrupt human trafficking and include a quick guidance document, an executive primer, and a policy guide. The operational-focused tools are designed to help agencies develop and implement the actions they decide to pursue and include outreach materials and a training guide.

The movement of overweight or heavy vehicles with increased axle and tire loads can cause premature pavement damage and accelerate deterioration. For state transportation agencies to effectively manage their pavement systems and consider alternative rehabilitation or design strategies for heavy-load movements, the impacts of such vehicles and the associated pavement damage must be assessed. Assessing pavement impacts under heavy loads is resource-intensive and challenging, given the iterative nature of the design process. Despite their significance, low-volume roads (LVRs) typically receive less attention than their high-volume counterparts because of resource constraints. Therefore, it is important to understand how state departments of transportation (DOTs) assess the impacts of heavy loads on LVRs, particularly because the design of LVRs differs significantly from that of typical high-volume roads.

NCHRP Synthesis 666: Design and Evaluation of Pavements for Low-Volume Roads with Heavy Loads, produced by TRB’s National Cooperative Highway Research Program, examines LVRs exposed to heavy, overweight, or nonstandard traffic, which can increase the risk of rapid deterioration and premature failure. The report focuses specifically on LVRs managed by state DOTs; practices of local agencies, such as those of cities, counties, and townships, are not included. Topics covered include pavement design and modifications, permitting requirements, structural impacts and failures, performance monitoring and maintenance strategies, springtime load restrictions, and case examples of design approaches for LVRs subjected to heavy loads.

Improving pedestrian safety continues to be critically important to ODOT’s mission to provide a safe and reliable multimodal transportation system. This research provides ODOT with refined tools to improve pedestrian safety at signalized intersections by developing enhanced guidance on when and where to implement Leading Pedestrian Intervals (LPI) either solely or in conjunction with complementary treatments such as Curb Extensions (CE). The guidance was informed by four major tasks: a literature review, a conflict-based field study, a driving simulator study, and development of an LPI suitability assessment tool. This research found that CEs decrease vehicle turning speed and shift conflicts from high/medium to low severity. For conflicts involving speed, both CEs & LPIs reduced conflicts, with the addition of the CE providing additional conflict reduction. The findings from this research support ODOT’s Strategic Action Plan as well as ODOT design and practice documents.

The University of South Florida’s Corrosion Research Laboratory previously developed a tendon imaging unit (TIU) capable of providing representative cross-section images of external tendons that show strand envelope position and the likelihood of grouting deficiencies. The objective of this work was to adapt the grout-based TIU for application to wax-filled external tendons. After characterization of the electrical properties of FDOT approved waxes, it became apparent that adaptation to wax-filled tendons would require sophisticated signal analysis to account for the limited difference between the dielectric constant for wax and air. An analysis approach was developed in which the magnetic signal is converted to a representative impedance signal considering a flaw-free, completely wax-filled condition. Comparison between the magnetic-signal recovered impedance and the measured impedance facilitates deficiency detection. Air void and water pocket deficiency detection with cross-section image recovery was demonstrated for a series of strand configurations and fill conditions. In a parallel thrust, an initial design for a rotation-free TIU was developed, and preliminary testing confirmed the capability of recovering strand position. This is a particularly promising advancement that with further development could result in increased ability to rapidly scan external tendons to facilitate bridge-scale testing or monitoring systems.

Rapid technological advances and the growing use of vehicle-based telematics are providing transportation agencies with real-time data that can improve safety, operations, and roadway performance. However, effective use of telematics data is complicated by challenges related to data access, privacy, standardization, and private-sector data sharing. Differences in the capabilities and needs of state and local departments of transportation (DOTs) also make it difficult to develop a single approach to integrating and using telematics data.

NCHRP Research Report 1197: Vehicle-Based Telemetric Data for State and Local Transportation Agencies, produced by TRB’s National Cooperative Research Program, examines the current use of telematics data by transportation agencies, including available data vendors and analytics platforms, agency practices and experiences, real-world applications, challenges and barriers to adoption, and potential actions and policies to help state DOT agencies of all sizes more effectively use telematics data.

State department of transportation (DOT) employees operate in dynamic, high-hazard environments. These conditions can lead to serious injuries and fatalities (SIFs), even when risks are rigorously identified. DOTs manage these risks through the safety programs they develop, implement, and maintain. A strong focus on eliminating SIFs not only protects employees but also strengthens safety culture, reduces workers’ compensation costs, and minimizes operational disruptions. DOTs often go beyond compliance-based safety measures to address SIFs, adopting proactive approaches to hazard recognition, employee engagement, fatigue management, and technology integration.

NCHRP Synthesis 670: Reducing Serious Injuries and Fatalities Among State DOT Employees, produced by TRB’s National Cooperative Highway Research Program, shares successful practices across state DOTs to accelerate the adoption of effective strategies and help DOTs collectively move toward the shared goal of zero SIFs. The synthesis examines data on factors contributing to SIFs, methods DOTs use to collect SIF information, and written practices focused on reducing SIFs. It also explores practices for assessing, managing, and mitigating employee fatigue and distraction; employee engagement and awareness of SIF-reduction training programs; and how individual states define SIFs and identify high-risk work activities and tasks. In addition, the synthesis examines technologies used to reduce the effects of equipment- and human-related factors that contribute to SIFs.

Nearly all U.S. transit agencies face operator workforce shortages driven by demographic challenges, turnover, and job quality concerns. An aging workforce and pandemic-era retirements have intensified these shortages, while increases in roadway fatalities, road rage, violent incidents, and other safety concerns may contribute to actual or perceived workplace hazards. Transit operators also face significant job stress because they bear substantial responsibility for schedules, passenger safety, fare collection, and vehicle operation while having limited control over many factors affecting their work. These conditions can contribute to a range of physical and mental health risks, including cardiovascular disease, musculoskeletal disorders, fatigue, and post-traumatic stress disorder.

TCRP Synthesis 190: Strengthening the Transit Workforce Through Operator Health and Wellbeing, produced by TRB’s Transit Cooperative Research Program, explores the psychosocial hazards faced by transit operators, the impacts of these hazards on operator health and wellbeing, and the state of the practice in policies and programs developed by transit agencies to address them. The synthesis finds that psychosocial hazards are a significant concern for transit operators, particularly growing verbal and physical aggression from passengers, and that operators face elevated risks of physical and mental health conditions. Transit agencies use a range of programs and practices to address these hazards and promote operator wellbeing, although funding, staffing, and awareness challenges may limit their effectiveness.

The transportation infrastructure in South Carolina includes many bridges that are load posted due to structural considerations (e.g., outdated design loads, members whose capacity is difficult to assess) resulting in substantial costs to the public. The significant number of posted bridges has an adverse effect on travel and commerce in South Carolina. Efficient bridge strengthening methods are described in this report to mitigate these effects. This report focuses on laboratory and field trials of strengthening methods for precast flat slab and channel girder bridges. The goal is provide a means for reducing the number of load-posted bridges through efficient strengthening. Strengthening methods were investigated and laboratory testing was conducted to verify the structural response pre- and post-strengthening. A cost evaluation of the most suitable strengthening methods was performed and selected solutions verified through field implementation and load testing. The outcomes of this research are expected to provide efficient means to minimize the number of load-posted bridges. The work described is part of a larger effort to extend the service life of bridges in South Carolina.

To be able to handle the statewide mobile lidar data ODOT collects efficiently, there is a need for a robust workflow with significant automation that can extract many types of features by effectively leveraging various feature extraction tools and algorithms to support applications. In particular, road characterization has been identified as a key application for information extraction from mobile lidar data. In this literature review, the team first provides a brief overview of the model inventory of roadway elements (MIRE 2.0) to help identify the attributes that are of interest as well as feasible to extract from mobile lidar data. Next, a review of the existing commercial software summarizes the common challenges in using these solutions for feature extraction and characterization tasks. Lastly, the existing work related to road characterization is reviewed covering the topics of ground filtering and road extraction, cross slopes and grades, and horizontal curve, followed by a summary of the benefits of using mobile lidar data as well as the challenges of the existing studies.

Reflective cracking is one of the primary causes of premature deterioration in asphalt-overlaid Portland cement concrete (PCC) pavements, reducing service life and increasing maintenance costs. Because crack initiation begins within the underlying PCC layer before becoming visible at the surface, conventional inspection methods have limited capability for early detection. This project developed and experimentally validated a hybrid experimental-numerical framework that integrates optical frequency domain reflectometry (OFDR)-based distributed fiber optic sensing (DFOS), laboratory-scale three-point bending tests, and finite element (ABAQUS) modeling to monitor and interpret bottom-up reflective cracking. Rectangular and semi-cylindrical asphalt-overlaid PCC specimens were instrumented with surface-bonded distributed optical fibers in a serpentine layout with 20-mm spacing. Controlled bending tests reproduced bottom-up crack initiation and propagation, with cracks consistently originating at a predefined notch within the PCC layer and propagating toward the asphalt overlay. The OFDR-based DFOS system identified localized strain concentrations associated with crack development; and finite element simulations reproduced the observed crack initiation location, propagation path, stress redistribution, and global structural response. The close agreement among laboratory observations, distributed strain measurements, and numerical predictions validates the framework and demonstrates the potential of OFDR-based DFOS for structural health monitoring and condition assessment of rehabilitated concrete pavements.

Transit agencies develop design standards or guidelines for transit stops, stations, and terminals that vary in content and level of detail. These standards are often included in documents that also provide guidance for other aspects of the transit system, such as guideways, maintenance facilities, and vehicles. However, these diverse standards have never been systematically compiled, compared, and summarized.

TCRP Research Results Digest 127: Review of Transit Station Design Guidelines, produced by TRB’s Transit Cooperative Research Program, compiles station dimensional guidance from multiple transit agency design manuals. The digest identifies eight key criteria common to many station design guides: level-of-service standards; runoffs at stairs and escalators; provision of stairs, escalators, and elevators; stair width; escalator width and speed; elevator queuing space; platform width or area; and platform edge clearance. The digest describes the measures identified for each of these eight criteria and discusses important considerations, particularly where guidance varies or provides nuanced recommendations across agencies. The digest summarizes one of 12 small research tasks conducted to support the development of new content for the Transit Capacity and Quality of Service Manual, Fourth Edition.

State departments of transportation (DOTs) are responsible for managing and maintaining highway systems and, in some cases, additional infrastructure such as airports. These operations expose their employees to a range of occupational hazards across varied environments, including high-speed work zones, heavy machinery operations, laboratory settings, shop facilities, and complex field operations involving construction and maintenance activities. Ensuring the safety of employees is a goal for all state DOTs, and personal protective equipment (PPE) is one tool used to support this goal. As defined by the Occupational Safety and Health Administration (OSHA), PPE “is equipment worn to minimize exposure to hazards that cause serious workplace injuries and illnesses.” PPE can minimize exposure to physical, electrical, mechanical, chemical, or other workplace hazards.

NCHRP Synthesis 669: Personal Protective Equipment: Policies, Programs, and Practices, produced by TRB’s National Cooperative Highway Research Program, examines state DOTs’ selection, use, procurement, tracking, maintenance, and replacement of PPE for construction and maintenance activities. It also explores emerging PPE technologies, employee training and communication, methods for gathering employee feedback, and approaches for evaluating PPE performance. It is important to emphasize that some states have their own occupational safety and health (OSH) policies and regulations that may or may not be more stringent than OSHA regulations. To provide a more nationally applicable report, this synthesis focuses on OSHA regulations rather than referencing specific state OSH policies or regulations. However, all OSH policies and regulations are intended to promote employee safety.