Lundi, 18 Janvier, 2021 - 20:15
This document serves as a quick reference guide for transportation professionals in State and local agencies that are interested in applying a systemic approach to road-safety management. This guide provides brief overviews of the systemic approach, common target crash types and their associated facility types, and contributing factors. It also provides a six-...
Lundi, 18 Janvier, 2021 - 20:15
The transportation-engineering community is transforming by integrating quantitative methods into the task development process. This report identifies opportunities to better understand the relationships between road safety and factors that affect traffic-crash occurrence and severity. In this report, current statistical-analysis methods and data sources used...
Lundi, 18 Janvier, 2021 - 20:00
This project established protocols to help evaluate the utilization of chemical stabilization methods to potentially improve the engineering behavior of problematic soils with and without soluble sulfates within the state of Montana. In addition, construction life cycle cost analyses were used to compare existing approaches used by MDT versus chemical...
Lundi, 18 Janvier, 2021 - 20:00
Nineteen state highway locations around south-central and southwestern Minnesota were evaluated during winter 2019-20 for the application of deicer “hot shots,” extra levels of salt or other chemical treatments used to deice roadways and maintain roadway driving levels of performance. Locations were selected based on previous recordkeeping that...
Lundi, 18 Janvier, 2021 - 19:45
The density and air void content of asphalt mixtures affect the durability and performance of asphalt pavements. Pavement longitudinal joints typically have a lower density than the mat because they receive less compaction than the center section of the mat for various reasons. The higher air void percentages resulting from lower densities can lead to high...
Lundi, 18 Janvier, 2021 - 19:45
This report was largely prepared in 2019 and early 2020 before the novel coronavirus that causes COVID-19 struck the United States. Economic shutdowns and social distancing measures were put in place in multiple cities and states beginning in March 2020 to ...
Lundi, 18 Janvier, 2021 - 19:45
This report explores the accessibility challenges that people face in remote areas. It demonstrates how state support can ensure access to essential services and reduce social and economic isolation where private markets fail to provide adequate transport connections. It provides a classification of policy interventions in different countries and reviews common...
Lundi, 11 Janvier, 2021 - 16:00
Management of traffic signal systems is a critical function for many transportation agencies. Thanks to advancements in technology, it is now possible to collect large amounts of data at signalized intersections, leading to the development of dozens of performance measures.
The TRB National Cooperative Highway Research Program's NCHRP Research Report...
Lundi, 11 Janvier, 2021 - 15:45
Using reclaimed asphalt pavement (RAP) has grown significantly since the oil embargo of the 1970s. The National Asphalt Pavement Association reported that over 71 million tons of RAP were used in 2014 (NAPA 2015). RAP was traditionally used in warm-mix asphalt (WMA) and hot-mix asphalt (HMA) construction, including conventional and thin HMA overlays, but there...
Lundi, 11 Janvier, 2021 - 15:45
This report explores the relationships between transportation systems management and operations (TSMO) strategies and cooperative driving automation (CDA). It presents a high-level concept of operations (ConOps) in support of the CARMA PlatformSM sponsored by the Federal Highway Administration Office of Operations Research and Development. Developing this...
Lundi, 14 Décembre, 2020 - 16:15
The Kentucky Transportation Cabinet (KYTC) maintains over two hundred steel bridges constructed with types of steel which are unknown. Kentucky Transportation Center (KTC) researchers have developed a procedure for determining steel tensile properties (0.2% yield strength and ultimate tensile strength) which can be used to help identify unknown steels. The...
Lundi, 14 Décembre, 2020 - 16:00
Non-exhaust emissions of particulate matter constitute a little-known but rising share of emissions from road traffic and have significant negative impacts on public health. This report synthesizes the current state of knowledge about the nature, causes, and consequences of non-exhaust particulate emissions. It also projects how particulate matter emissions...
