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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 - January/February 2017

Date:
January/February 2017
Issue No:
Vol. 80 No. 4
Publication Number:
FHWA-HRT-17-002
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 (FHWA) 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 www.ntis.gov 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: www.ntis.gov
Email: customerservice@ntis.gov

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
Email: report.center@dot.gov

For more information on R&T communications products available from FHWA, visit FHWA’s Web site at www.fhwa.dot.gov, the FHWA Research Library at www.fhwa.dot.gov/research/library (or email fhwalibrary@dot.gov), or the National Transportation Library at ntl.bts.gov (or email library@dot.gov).

 

Analysis of Construction Quality Assurance Procedures on Federally Funded Local Public Agency Projects (Report)

Publication Number: FHWA-HRT-15-008

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Approximately 20 percent of the Federal-aid Highway Program is invested annually in infrastructure projects by local public agencies. Previous Federal and State reviews have found significant weaknesses or inconsistencies in assurance practices for construction quality in such projects. In response, this report documents current quality assurance practices from both State departments of transportation and local public agency perspectives.

The report identifies specific issues or areas of weakness in practices for ensuring quality assurance, highlights existing successful practices, and makes recommendations to generally improve construction quality assurance across the full spectrum of local public agency projects and State DOT programs.

State DOTs need to improve oversight of quality assurance procedures and develop practical procedures for local public agencies, while taking into account how to make the process more efficient for the various types, sizes, and scopes of projects that receive Federal funds. Most of the recommendations in the report can be addressed and implemented at the State or project level. Others may require action by the FHWA division office or headquarters. Recognizing that there are significant differences in capabilities and project types for local public agencies, the recommendations consider both large and small agencies and differences among State DOT programs.

The document is available to download at www.fhwa.dot.gov/publications/research/infrastructure/pavements/15008/index.cfm.

 

The Universal Simple Aging Test (TechBrief)

Publication Number: FHWA-HRT-15-054

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The Universal Simple Aging Test (USAT) is a new thin-film short- and long-term aging test developed by the Western Research Institute, with funding and guidance provided by FHWA. This report provides an overview of the USAT, which is an alternative to testing for asphalt binders using standard rolling thin-film ovens and pressure-aging vessels. The USAT is very comparable to these standard testing methods for hot-mix and warm-mix asphalt regarding intermediate- and high-temperature characteristics.

Performing the short-term USAT aging requires 50 minutes, which is 35 minutes less than required by other standard test methods. Cleanup of the equipment after the test also is greatly simplified for the USAT. The time required to perform the long-term component of the USAT is 8 to 12 hours less than the standard test. The only change in aging for hot-mix asphalt compared with warm-mix asphalt is to adjust the oven temperature from 300 to 265 degrees Fahrenheit (150 to 130 degrees Celsius). Applying the USAT offers several advantages because of its increased simplicity and consistent results.

The document is available to download at www.fhwa.dot.gov/publications/research/infrastructure/pavements/15054/index.cfm.

 

Active Traffic Management: Comprehension, Legibility, Distance, and Motorist Behavior in Response to Selected Variable Speed Limit and Lane Control Signing (Report)

Publication Number: FHWA-HRT-16-037

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Active traffic management incorporates a collection of strategies enabling the dynamic management of recurrent and nonrecurrent congestion based on prevailing traffic conditions. These strategies help to increase peak capacity, smooth traffic flows, and enhance safety on busy major highways.

This report describes four studies (one in a laboratory setting, one in a field setting, and two in a driving simulator) researching two particular active traffic management approaches: variable speed limits and lane control signs. The laboratory study involved participants viewing a series of lane control scenes from the perspective of a driver. Participants described what they thought the signs were intended to mean and what they would do in response to the signs. Subsequently, researchers asked participants which sign content alternatives they preferred. In the related field test, researchers assessed the legibility distance of a selected subset of signalternatives.

Two experiments conducted in FHWA’s Highway Driving Simulator examined how drivers might behave in response to various scenarios employing lane control signs and variable speed limits. The experiments recorded driver lane choice, speed, and eye-glance behavior in a dynamic environment in response to the same signs and scenarios examined in a static environment during the previous field test.

The report synthesizes and summarizes the important contributions made by these studies. The study findings will contribute to the development of guidelines for consistent and effective signing for active traffic management.

Although this document provides useful information on comprehension, preferences, human behavior, and decisionmaking with regard to signing, the Manual for Uniform Traffic Control Devices provides official FHWA guidance in this area.

The document is available to download at www.fhwa.dot.gov/publications/research/safety/16037/index.cfm.