The US Transportation Collection consists of documents from across all transportation modes with specific focus on research reports from US DOT, state DOTs, and other transportation organizations.
Bookmark this collection: https://rosap.ntl.bts.gov/collection_ust or https://doi.org/10.21949/1530857.
The interaction between tires and the road surface is crucial for maintaining vehicle stability and safety. The frictional forces at the tire-road interface, along with the coefficient of friction, affect vehicle dynamics, influencing transportation safety. Rapid advancements in transportation technology, infrastructure demands, and safety regulati
...
Following its adoption of the new AASHTO Bridge Element Inspection Manual, the Florida Department of Transportation (FDOT) has been collecting bridge element condition data in order to use the AASHTO’s Bridge Management (BrM) software. Now, to aid the Department in satisfying the various federal requirements and prepare for anticipated changes at t
...
Secondary crashes resulting from traffic queues are a significant national safety concern. Traffic Incident Management (TIM), which involves coordinated multi-agency response to roadway incidents, is widely recognized as an effective approach to mitigating these crashes. This study aimed to develop a library of after-action case studies to support
...
Despite the fact that highway work zones represent a required element of maintaining and improving the transportation network, the resulting changes in traffic patterns, narrowed right-of-way, and other construction activities can lead to an increased risk for traffic crashes and related injuries or fatalities. This research sought to identify the
...
Reestablishing passenger rail service between Salisbury and Asheville presents a significant opportunity to strengthen North Carolina’s economy and transportation network. By connecting major population centers—including the Charlotte metro, the Piedmont Triad, the Research Triangle, and the Blue Ridge region—the corridor would enhance mobility for
...
The Indiana Department of Transportation’s (INDOT) roadside management program is tasked with multiple items across the state’s 39,000 lane miles. Roadside maintenance is an essential task that keeps INDOT’s rights-of-way (ROWs) safe and functional for drivers. Most roadside vegetation maintenance work for INDOT is outsourced, and INDOT’s in-house
...
Laboratory investigations and results from a year-long field trial demonstrated that plain Type IL cement and slag cement concrete that was internally cured by superabsorbent polymer (SAP) has increased strength and durability compared to SAP-free mixtures, mixtures containing colloidal nanosilica, and mixtures that were externally cured with a sur
...
Conventional high-speed inertial profilers provide valid international roughness index (IRI) measurements under favorable conditions but experience performance degradation at low speeds, during deceleration and acceleration, or when coming to a stop. Due to these limitations, Louisiana DOTD does not compute performance index (PI) values for certain
...
Intersection capacity, defined as the maximum number of vehicles that can pass through an intersection within a given time, directly influences traffic flow, congestion levels, and overall network efficiency. Accurate estimation of intersection capacity is essential for effective roadway planning, design, operation, and management. Intersection cap
...
This research project expanded on the three previous LTRC geotechnical database efforts to improve and advance geotechnical data management within the Louisiana Department of Transportation and Development. This project facilitated the implementation of Bentley’s OpenGround Cloud (OpenGround). The project uploaded historical boring log images and d
...
The objective of this research was to determine the efficacy and cost-effectiveness of the application of tire-derived aggregate (TDA) in stormwater treatment and management systems. We reaffirmed that TDA is an excellent means of retaining phosphate (soluble reactive phosphorus) in stormwater runoff. In addition, we found that biofilms grow on TDA
...
This research examines the value of financing infrastructure improvements through bonding versus a program of pay-go improvements. Postponed construction becomes more costly in nominal terms because inflation raises the cost of construction over a longer period before construction begins. However, postponements can also create a variety of other si
...
The objective of this project is to develop knowledge, tools, and protocols to inform best practice standards for effective implementation of biochar in bioretention systems (BRSs) for treating roadway runoff. This project will be performed in two phases, with the first phase (this report) focusing on biochar production, characterization, and conta
...
A study funded by the Tennessee Department of Transportation (TDOT) and the Federal Highway Administration under RES2024-003 was conducted to assess the occurrence of wildlife-vehicle crashes (WVCs) along TDOT maintained routes in Tennessee and to explore potential mitigation strategies. WVC hotspots were identified by analyzing wildlife incident d
...
Pile foundations were often driven into intermediate geomaterials (IGM) to support heavy civil infrastructures like bridges due to shallow bedrock stratigraphy. Thus, the pile foundations of this region must rely on the resistance contributed from the IGM layers. However, IGM is a transitional geomaterial between soil and rock, that needs to be bet
...
Texas Department of Transportation (TxDOT) determines unit prices of pay items using the historical bids-based estimation method and then develops an engineer’s project appraisal. The engineer's estimate is used to assess the bids and select the bidder. However, the unit price of a work item is heavily affected by various project-specific and exter
...
Reinforced soil slopes (RSSs) can be a feasible solution for embankments where there exist right of way restrictions, environmental issues, rolling or mountainous topography, unfavorable geology, and other limiting fac-tors. They can be an alternative to retaining walls or importing select fills to construct steeper, stable embankment slopes where
...
In 2021, the Virginia Department of Transportation (VDOT) collaborated with the National Cooperative Highway Research Program (NCHRP 20-44(26)) project research team to develop three specifications for chip seals, microsurfacing, and fog seals, incorporating recommendations from guidelines developed under the NCHRP 14-37 project and American Associ
...
The Alabama Department of Transportation (ALDOT) is currently using the Alabama Design and Analysis of Pavement Thickness (ADAPT) software for their structural pavement design process, which is based on the 1993 American Association of State Highway and Transportation Officials (AASHTO) Pavement Design Guide. In 2008, the American Association of St
...
This research was completed to provide recommendations to create a standardized operational framework or pilot training program for Utah Department of Transportation (UDOT) Unmanned Aircraft Systems (UAS) which are used for infrastructure inspections, traffic monitoring, emergency response, and data collection. This will improve safety practices, r
...
Links with this icon indicate that you are leaving a Bureau of Transportation
Statistics (BTS)/National Transportation Library (NTL)
Web-based service.
Thank you for visiting.
You are about to access a non-government link outside of
the U.S. Department of Transportation's National
Transportation Library.
Please note: While links to Web sites outside of DOT are
offered for your convenience, when you exit DOT Web sites,
Federal privacy policy and Section 508 of the Rehabilitation
Act (accessibility requirements) no longer apply. In
addition, DOT does not attest to the accuracy, relevance,
timeliness or completeness of information provided by linked
sites. Linking to a Web site does not constitute an
endorsement by DOT of the sponsors of the site or the
products presented on the site. For more information, please
view DOT's Web site linking policy.
To get back to the page you were previously viewing, click
your Cancel button.