National ITS Architecture

Building a Bridge to the Public: The Alaska Experience

One Extraordinary Barn

Bridging the Centuries: Moving Virginia's Bridge Program Into the 21st Century

TEA-21: "A Historic Piece of Legislation

Ultra-Thin Whitetopping

The First Channel Bridges

Staying in the Loop: The Search for Improved Reliability of Traffic Sensing Systems Through Smart Test Instruments

Departments

Editor's Notes

Along the Road

Internet Watch

Recent Publications

Conferences/Special Events Calendar

NHI Update

Public Roads (ISSN 0033-3735; USPS 516-690) is published bi-monthly by the Office of Research and Development, Federal Highway Administration(FHWA), 400 Seventh Street SW, Washington, DC 20590.

Contact Editor
Bob Bryant

Assistant Editor Kandace Studzinski

Distribution Manager Judy Dakin

All articles are advisory or informational and should not be construed as having regulatory effect.

Contents of this publication may be copied provided credit is given to Public Roads and the authors.

The following are brief descriptions of selected reports recently published by the Federal Highway Administration’s (FHWA) Office of Research and Development. All publications are available from the National Technical Information Service (NTIS). In some cases, limited copies of publications are available from the R&T Report Center.

When ordering from NTIS, include the NTIS PB number (or publication number) and the publication title. For customers outside the United States, Canada, and Mexico, the cost is double the listed price. Address requests to:

National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
Telephone: (703) 487-4650

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

Federal Highway Administration
R&T Report Center, HRD-11
9701 Philadelphia Court, Unit Q
Lanham, MD 20706
Telephone: (301) 577-0818

Mechanistic Evaluation of Test Data From LTPP Flexible Pavement Test Sections, Vol. 1: Final Report

Publication No. FHWA-RD-98-012
This report describes how well some existing asphalt pavement mechanistic-empirical distress-prediction models performed when compared to data collected as part of the National Long-Term Pavement Performance (LTPP) program.

The first phase of data analysis involved using the deflection test data to backcalculate pavement layer moduli values. Using representative values of the layer moduli, structural analyses were performed for up to 140 axle-load configurations for the selected test sections. The Asphalt Institute and the Shell procedures were then used to predict fatigue cracking and rutting damage.

Based on the new results, new forms of the fatigue cracking models have been proposed.

The NTIS number is PB98-146228; the cost is $33 for a paper copy or $17 for the report on microfiche.

Field Evaluation of a New Aluminum Alloy as a Sacrificial Anode for Steel Embedded in Concrete

Publication No. FHWA-RD-98-058
This study evaluates the use of sacrificial cathodic protection for reinforced and prestressed concrete bridge members. Cathodic protections (CP) using impressed current is an accepted and common method used to provide corrosion protection to steel in concrete. Sacrificial cathodic protection is relatively easy to apply, does not require the anode to be electrically isolated from the steel, and does not require an external power supply.

This report examines the performance of existing sacrificial alloys in different environments for sacrificial CP.

The NTIS number is PB98-147135; the cost is $27 for a paper copy or $12 for the report on microfiche.

Impacts on State and Local Agencies for Maintaining Traffic Signs Within Minimum Retroreflectivity Guidelines

Publication No. FHWA-RD-97-053
FHWA has developed guidelines for minimum retroreflectivity levels for four groups of signs: yellow/orange-on-black warning signs, black-on-white regulatory signs, white-on-red regulatory signs, and white-on-green guide signs.

As part of the development of these recommended values, several states and local highway agencies helped FHWA by measuring the retroreflectivity of a pre-determined sample of signs, providing data on sign-replacement costs and offering information on proposed retroreflectivity values. FHWA could see whether the states and agencies were able to maintain signs within the established regulations.

This report presents the data the states and agencies collected. This data was used to estimate the total cost for replacing signs on the nation’s highways that did not meet minimum retroreflectivity values.

The NTIS number is PB97-147127; the cost is $27 for a paper copy or $12 for the report on microfiche.

User Guidelines for Waste and By-Product Materials in Pavement Construction

Publication No. FHWA-RD-97-148
This document details a study designed to develop a concise manual on the latest available information on the use of waste or by-product materials in pavement construction applications. The manual provides technical guidance for highway and materials engineers, waste and by-product generators, and others involved in making decisions regarding the use of waste and by-product materials in highway construction.

This manual describes 19 waste and by-product materials from domestic, industrial, and mining sectors, and six high-volume pavement construction applications.