A new prestressing system, named Adaptive Prestressing System, has been proven in this study to be an innovative technique that holds great promise as a transformative, more efficient, and safer prestressing method for concrete crossties in railway systems. The TRB IDEA (Innovations Deserving Exploratory Analysis) Program's Rail Safety IDEA Final Report 33: Adaptive Prestressing System for Conc...

The TRB Centennial Book is available for purchase in ebook or print format. In The Transportation Research Board, 1920–2020: Everyone Interested Is Invited , author Sarah Jo Peterson tells the story of how people and institutions created and have continued to shape TRB. In a compelling narrative accompanied by more than 150 images exploring the history of transportation and research, she argues...

The past few years have seen some significant advances in concrete technology. For example, newer concrete incorporating advances in admixtures and cementitious materials has emerged. The TRB National Cooperative Highway Research Program's NCHRP Synthesis 544: Concrete Technology for Transportation Applications documents how state departments of transportation select and deploy concrete technol...

The Wisconsin DOT issues both single- and multi-trip permits for Oversize–Overweight (OSOW) vehicles. As the number of OSOW vehicle permits issued in Wisconsin have increased in recent years, the management and analysis of OSOW permit data has become more labor-intensive and time-consuming. This "Research Pays Off" feature in  TR News edition 324 (November-December 2019), by Hani Titi, Nic...

The majority of instances of explicit consideration of service life design has been limited to signature bridges and other projects where extended service lives (in other words, greater than 100 years) are specified by the owner. Many state departments of transportation and other transportation agencies have recognized the importance of implementing service life design for typical highway bridg...

This article is adapted from The Transportation Research Board, 1920–2020: Everyone Interested Is Invited , to be published by the National Academies Press in January 2020. TRB can be best understood as an infrastructure—one that people purposely designed, carefully constructed, and devotedly maintained to share and strengthen knowledge about transportation. The core missions and structures tha...

There are several best management practices that are good at removing particulate-bound pollutants by settling, filtering, and, in the case of wetlands, settling, uptake, and incorporation of pollutants into biological matter (e.g., natural organic matter). However, a longstanding goal of stormwater treatment is the removal of the stormwater pollutant fraction that cannot be readily settled or ...

The November-December 2019 issue of TR News - with a focus on climate change resilience - is available in hard copy and digital copy for subscribers. For those who are not subscribers, the table of contents is available. Other feature articles in the issue include ones on the history of both TRB and transportation in general and a preview of the TRB Annual Meeting slated for January in Washingt...

Concrete is a porous material that allows materials to move through it. The number of pores connected in the concrete, also known as the permeability, influences the ability of fluids to penetration the concrete. And this permeability parameter is an important transport mechanism for freeze-thaw damage, corrosion, alkali silica reaction, and sulfate attack. The TRB Innovations Deserving Explora...

Load testing of bridges to assess bridge performance has been in practice since at least 1891 in Switzerland. In times when engineering models were not as accurate and available as today, a critical step in the construction of a bridge was to load test prior to opening or during the opening ceremony of the bridge. Several bridges, including ones in Serbia, Switzerland, and France, collapsed dur...

Expansive soils, also known as swell-shrink soils, have been a problem for civil infrastructure such as roads and foundations since ancient times. These soils swell and shrink with changes in moisture content, causing buildings and pavements to crack. The reason for this behavior is the presence of the heaving/swelling mineral that expands when exposed to water. These soils are present in the m...

Concrete is the most widely used synthetic material on earth. In the U.S., more than 75 percent of bridges and more than 60 percent of interstate highways are made of concrete. There is no other bulk material on the horizon that could replace concrete as the backbone for our increasing demands in infrastructures. Despite several decades of studies, concrete bridges, highways and infrastructures...

Papers released the week of October 7 through the Transportation Research Record: Journal of the Transportation Research Board OnlineFirst portal include the following: Defining Psychometric Variables Related to Use of Autonomous Vehicles - Don MacKenzie, Andisheh Ranjbari, Yanbo Ge, Eric Barber, Elyse O'C. Lewis Implications of Including Reclaimed Asphalt Pavement Materials to Performance of B...

Information exchanged during the 97th Annual Meeting of the Transportation Research Board in a session titled "Relationship Between Laboratory Cracking Tests and Field Performance of Asphalt Mixtures" is captured in Transportation Research Circular E-C251: Relationship Between Laboratory Cracking Tests and Field Performance of Asphalt Mixtures . The document explores a significant amount of wor...

Traditionally, pavement management decision-making has relied on surface cracking as an indicator of structural condition. However, with early-intervention preservation activities to extend the life of pavements, surface cracks no longer are a reliable indicator of structural condition. In the past 15 years, traffic speed deflection devices (TSDDs) have been developed to measure pavement struct...

More than 90 percent of highways and roads in the United States are built using hot-mix asphalt (HMA) or warm-mix asphalt mixtures, and these mixtures now recycle more than 99 percent of some 76.2 million tons of reclaimed asphalt pavement (RAP) and about 1 million tons of recycled asphalt shingles (RAS). According to the National Asphalt Pavement Association, cost savings in 2017 totaled appro...

Papers released the week of September 23 through the Transportation Research Record: Journal of the Transportation Research Board OnlineFirst portal include the following: Impact of Market-Rate Residential Parking Permit Fees on Low-Income Households - Alex Okashita, Richard Willson Privacy Risk of Connected Vehicles in Relation to Vehicle Tracking when Transmitting Basic Safety Message Type 1 ...

Papers released the week of September 16 through the Transportation Research Record: Journal of the Transportation Research Board OnlineFirst portal include the following: Performance of Chip Seal Treatments in Two Different Climatic Regions - Benjamin Worel, Adriana Vargas-Nordcbeck, Michael C. Vrtis When Should Agencies Post Weight Limits on Local Highways in New York State? - David P. Orr Ro...

Global business and tourism depend heavily on the efficient operation of airports and movement of passengers, baggage, and cargo across many areas. With increasing demand and connectivity requirements for airports comes the need for more sophisticated simulation and modeling tools to validate design assumptions. Furthermore, airport design and planning decisions have significant impacts on poli...

The performance of flexible and rigid pavements is known to be closely related to properties of the base, subbase, and/or subgrade. However, some recent research studies indicate that the performance predicted by this methodology shows a low sensitivity to the properties of underlying layers and does not always reflect the extent of the anticipated effect, so the procedures contained in the Ame...

“Pavement condition data” are essential inputs to the process of managing airport pavements and ensuring safe operations. The technology available today to collect pavement condition data is considerably different from that available even 20 years ago, and new technologies are being developed and introduced into practice at a rapid pace. ACRP Research Report 203: Guidelines for Collecting, Appl...

Papers released the week of September 2 through the Transportation Research Record: Journal of the Transportation Research Board OnlineFirst portal include the following: High-Performance Impact-Resistant Concrete Mixture for Transportation Infrastructure Applications - Qian Zhang, Jovan Tatar, Kamal Baral For more than 50 years, the Transportation Research Record has been internationally recog...

Pavement smoothness (or roughness) is used by state highway agencies for monitoring network condition and other purposes such as assessing construction quality and optimizing investments in preservation, rehabilitation, and reconstruction. States are also required to report the International Roughness Index (IRI) as an element of the federal Highway Performance Monitoring System (HPMS). Because...

Papers released the week of August 26 through the Transportation Research Record: Journal of the Transportation Research Board OnlineFirst portal include the following: On the Spatial Evolution of Traffic State Transitions: Empirical Observations and General Features - George Saman, Soyoung Ahn, Paulina Reina Study of Factors Affecting Curing of Asphalt Emulsion Tack Coats - Daniel Swiertz, Hus...

Papers released the week of August 19 through the Transportation Research Record: Journal of the Transportation Research Board OnlineFirst portal include the following: US Commuter Rail Renaissance: A 30-Year Progress Report - David O. Nelson, Katherine K. O’Neil System-Level Fault Prognosis for High-Speed Railway On-Board Systems - Yu Zang, Wei ShangGuan, Bai-Gen Cai, Hua-Shen Wang, Lovlesh Ka...

Some concrete pavements commonly used at airports are susceptible to the destructive effects of alkali-silica reaction ( ASR).  The presence of ASR on concrete pavements can have a devastating effect on pavement performance, not only in terms of reduced functionality, but also in terms of shortened service lives.  The focus of  ACRP Synthesis 96:   Practices to Mitigate Alka...

TRB’s Technical Activities Division has released Transportation Research Circular E-C248: 12th International Conference on Low-Volume Roads, highlighting topics including road surfaces, geotechnology, cold regions and climate change, pavement management, planning and economics, unpaved roads management, geosynthetics in low-volume roads, drainage and stream crossings, climate change resiliency,...

TRB’s National Cooperative Highway Research Program (NCHRP) Synthesis 531 documents agency practices, challenges, and successes in conducting automated pavement condition surveys. The report also includes three case examples that provide additional information on agency practices for conducting automated pavement surveys. Pavement condition data is a critical component for pavement management s...

TRB’s National Cooperative Highway Research Program (NCHRP) Synthesis 537: Impact of Asphalt Thickness on Pavement Quality documents transportation agency policy for lift thickness and minimum compaction requirements on resultant asphalt pavement quality. To achieve expected pavement performance, it is important that asphalt concrete (AC) have adequate density. A critical factor in achieving th...

The notion of an aging and under-funded infrastructure in the United States is widely accepted. Current legislation calls for performance targets to be established to aid not only in the administering of funds, but also to assist states in identifying high-risk practices and roadways within their own networks. In addition to the performance targets, agency officials are looking to design and co...