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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Public Roads - May/June 2017

May/June 2017
Issue No:
Vol. 80 No. 6
Publication Number:
Table of Contents

Communication Product Updates

Communication Product Updates

by Lisa A. Shuler of FHWA's Office of Corporate Research, Technology, and Innovation Management

Below are brief descriptions of communications products recently developed by the Federal Highway Administration’s Office of Research, Development, and Technology. All of the reports are or will soon be available from the National Technical Information Service (NTIS). In some cases, limited copies of the communications products are available from FHWA’s Research and Technology (R&T) Product Distribution Center (PDC).

When ordering from NTIS, include the NTIS publication number (PB number) and the publication title. You also may visit the NTIS Web site at to order publications online. Call NTIS for current prices. For customers outside the United States, Canada, and Mexico, the cost is usually double the listed price. Address requests to:

National Technical Information Service
5301 Shawnee Road
Alexandria, VA 22312
Telephone: 703–605–6000
Toll-free number: 1–888–584–8332
Web site:

Requests for items available from the R&T Product Distribution Center should be addressed to:

R&T Product Distribution Center
Szanca Solutions/FHWA PDC
700 North 3rd Avenue
Altoona, PA 16601
Telephone: 814–239–1160
Fax: 814–239–2156

For more information on R&T communications products available from FHWA, visit FHWA’s Web site at, the FHWA Research Library at (or email, or the National Transportation Library at (or email

Automated High-Performance Liquid Chromatography Saturate, Aromatic, Resin, and Asphaltene Separation (TechBrief)

Publication Number: FHWA-HRT-15-055

dep11_3Dividing a material into its constituent parts is necessary to define its composition. Researchers can use these compositional analyses for binder formulation through blending, rejuvenation, and modification, as well as for predicting physical performance. The most common type of analysis divides a crude oil or asphalt into saturate, aromatic, resin, and asphaltene fractions. This technical brief focuses on the use of an automated high-performance liquid chromatography process that also further separates the asphaltene fraction.

Developed by scientists at the Western Research Institute, the novel separation process is called asphaltene determinator. The process reduces the time involved to complete a separation from days to hours. Researchers are exploring separation profiles from the process to develop indicators that correlate with binder performance.

The technical brief includes an overview of how to conduct the separation, as well as initial results from FHWA’s tests of binders at varying degrees of aging. More work is needed to further develop and validate these correlations.

The document is available to download at

Traffic Bottlenecks: Identification and Solutions (Report)

Publication Number: FHWA-HRT-16-064

dep12_2This report discusses a research project aimed at developing practical methods for prioritizing and mitigating traffic bottlenecks, one of the top causes of surface transportation congestion in the United States. Researchers developed a new approach for ranking traffic bottlenecks and a playbook of 70 bottleneck mitigation strategies. The report includes a benefit-cost analysis of five low-cost mitigation strategies and research on three innovative mitigation strategies that are not currently used in the United States.

In advancing a new approach for ranking traffic bottlenecks, researchers created a data-driven software tool with numerous performance measures to identify congestion and bottlenecks. In parallel, the team conducted extensive traffic simulations to assess the operational benefits of less frequently used strategies as opposed to popular strategies, such as ramp metering, which have been extensively researched and implemented in recent decades.

The project also focused on low-cost solutions rather than solutions that require significant infrastructure investments or advanced vehicle technologies. These low-cost solutions included the use of dynamic lanes, contraflow or reversible lanes, and hard-shoulder lanes; lane-width reduction; and modest extension of auxiliary lanes.

Research results demonstrated that these solutions produced favorable benefit-cost ratios with only minor modifications to existing infrastructure. Researchers further developed preliminary design guidance on signing, signalization, and striping for these strategies, and began a followup human factors study for two of the strategies.

The congestion bottleneck identification tool is available from Chris Melson,, or Joe Bared, This report may be of interest to practitioners involved in transportation operations. It is available to download at

Integrated Corridor Management and the Smart Cities Revolution: Leveraging Synergies (Report)

Publication Number: FHWA-HOP-16-075

dep13_0In 2014, the U.S. Department of Transportation defined a smart (or connected) city as a system of interconnected systems. These include employment, health care, retail, transportation, entertainment, public services, residences, and energy distribution. This system of systems is tied together by information and communications technologies that transmit and process data about a wide variety of activities within the city.

Conceptually, integrated corridor management (ICM) can be viewed as a practical application of a smart cities objective within the defined parameters of a corridor, not necessarily citywide. The ICM approach is based on three fundamental concepts: a corridor-level operations nexus; agency integration through institutional, operational, and technical means; and active management of all participating corridor assets and facilities. The goal of ICM is for transportation networks to realize significant improvements in the efficient movement of people and goods through aggressive, proactive integration of existing infrastructure along major corridors.

Because smart cities and ICM are fundamentally similar in terms of their requirements and objectives, this primer focuses on opportunities for codeployment synergies and how approaches and lessons learned from one initiative can be translated to the other. The report explores opportunities to effectively integrate strategies institutionally, operationally, and technically, both by leveraging existing platforms and considering new options for coordination between ICM and smart cities stakeholders. It also identifies potential challenges to integrating ICM and smart cities, along with potential solutions.

The intended audience for this report includes stakeholders from State and local transportation departments, metropolitan planning organizations, city agencies, and other organizations in the public and private sectors that provide services within a city or metropolitan area and are seeking to provide those services in a smarter, more efficient, and sustainable manner. This report aims to encourage these groups to think broadly about how to go about creating smart cities and how ICM can help achieve those goals.

The document is available to download at

Dimensional Stability of Grout-Like Materials Used in Field-Cast Connections (TechNote)

Publication Number: FHWA-HRT-16-080

dep14This technical note provides information about current approaches to quantifying the dimensional stability of grouts and grout-like materials, including those categorized as nonshrink cementitious grouts, and highlights some of the limitations of the test methods currently in use. The document proposes additional methods of materials testing to better quantify dimensional stability, as well as strategies to help mitigate some of the shrinkage observed in these types of materials.

Some grouts, especially those classified as nonshrink grouts, have displayed cracking mainly linked to their poor dimensional stability when used in connection details during bridge construction projects. The typical standards and test methods may provide an incomplete picture of the overall performance regarding the dimensional stability of these materials. Two common test methods have a series of shortcomings that researchers should consider when evaluating the dimensional stability of grout-like materials. For example, both methods provide a qualitative performance comparison rather than a quantitative assessment of the likelihood of shrinkage and expansion.

To provide a more direct correlation to shrinkage and potential cracking issues in these types of materials, FHWA recommends the use of additional test methods that might be more directly related to the real-world performance of these materials.

The researchers recommend internal curing as a convenient strategy to reduce shrinkage deformations and, consequently, shrinkage cracking. The inclusion of internal curing in prebagged grout materials could be implemented in the field as a grout extension or even as part of the premix material. This would also facilitate curing operations, especially in difficult-to-access locations.

This document is available to download at