U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
Federal Highway Administration Research and Technology
Coordinating, Developing, and Delivering Highway Transportation Innovations
This magazine is an archived publication and may contain dated technical, contact, and link information.
|Publication Number: FHWA-HRT-10-006 Date: September/October 2010|
Publication Number: FHWA-HRT-10-006
Issue No: Vol. 74 No. 2
Date: September/October 2010
Along the Road is the place to look for information about current and upcoming activities, developments, trends, and items of general interest to the highway community. This information comes from U.S. Department of Transportation (USDOT) sources unless otherwise indicated. Your suggestions and input are welcome. Let's meet along the road.
USDOT and the National States Geographic Information Council (NSGIC) recently began strategic planning for Transportation for the Nation, an initiative to coordinate collection of nationally significant geospatial transportation data with an emphasis on road centerlines.
Data on street networks (based on centerline data) are critical to a variety of geospatial information products. They support Enhanced 9-1-1 dispatching, mail and parcel delivery, response and relief efforts during major disasters, online sales tax collection, mapping, geocoding (the process of converting addresses into geographic coordinates), intelligent transportation systems, and automated vehicle routing and location systems. Currently, no national program exists for collecting transportation geospatial data from Federal, State, regional, and local sources.
USDOT's Research and Innovative Technology Administration will manage the project with help from a steering committee of representatives from other Federal agencies, NSGIC, State departments of transportation (DOTs), and other stakeholders. USDOT will hold workshops at various transportation and geographic information system-focused conferences throughout 2010. The final strategic plan for Transportation for the Nation, expected in spring 2011, will incorporate input and ideas gathered from the workshops.
For more information, visit www.transportationresearch.gov/TFTN.
In May 2010, Federal Highway Administrator Victor Mendez kicked off a series of workshops to improve the ability of small businesses to compete for Federal transportation contracts and engage more women and minorities in construction careers. The events are part of a national effort to ensure participation by small and disadvantaged business enterprises (DBEs) in the Nation's economic recovery and to help States meet their goals for awarding contracts to DBEs.
The workshops, held between May and November 2010, focus on specific federally funded transportation projects. The goal is to help minority- and women-owned DBEs learn about and better position themselves to take advantage of contracting opportunities. For example, the May workshop held in Denver, CO, gave local trade unions, construction contractors, and minority- and women-owned businesses an opportunity to meet with transportation officials regarding the construction of two light-rail commuter lines planned by the Colorado Department of Transportation and the Denver Regional Transportation District.
For more information on USDOT's DBE program, visit www.dotcr.ost.dot.gov/asp/dbe.asp.
The Texas Department of Transportation (TxDOT) established a new method for identifying alkali-silica reactivity (ASR), which leads to cracking in concrete, in the early stages of development. The new method involves placing a polished concrete sample suspected of having ASR problems into a room with atomized water to create a fog condition that maintains a constant temperature and a relative humidity of 100 percent. TxDOT researchers found that this step makes the ASR gel more visible, which allows for easier identification of the specific reactive particles.
|Identifying ASR gel in this concrete sample (top) became much easier once researchers viewed the sample (bottom) in the fog room, where the ASR gel is easily identifiable by its white color.|
Prior to this discovery, isolating the cause of cracking was challenging in very early stages of ASR development because of the gel's limited visibility; there was little direct evidence that the aggregate was experiencing dissolution. With the new method, however, researchers can identify the quantity of potentially reactive particles more accurately and confirm the presence of ASR. The method is not as conclusive in later stages of development, as the gel tends to remain a solid. However, this test may not be needed in later age stages because typically the evidence of ASR as the primary cause of distress is more easily identified.
The main challenge with the new method is determining the duration of time the specimen must stay in the fog room. If a sample stays too long, copious amounts of gel can form, making it difficult to determine which aggregate is responsible for generating the gel. Duration depends on the sample and the extent of ASR. TxDOT recommends daily monitoring and beginning evaluation as soon as ASR gel is observed, which could be as soon as 1 day or as long as 1 week.
FHWA and the American Transportation Research Institute have developed a Web-based tool to help identify key traffic chokepoints on some of the Nation's busiest freight routes. The Freight Performance Measures tool, or FPMweb, tallies operating speeds for trucks along 25 freight-heavy interstate highways.
Available at www.freightperformance.org, FPMweb is a first-of-its-kind effort to capture information on truck travel speeds from around the country through onboard global positioning system (GPS) and satellite technology. Low speeds reflect congestion levels at a particular location and time of day.
The tool is designed to help State and local transportation agencies prioritize their highway investments to target critical congestion needs. Businesses and freight companies also can use the tool to make more strategic decisions about trip scheduling and route selection to avoid congested areas.
Visit www.freightperformance.org for more information.
The Vermont Agency of Transportation (VTrans) is studying how jointless bridges respond to thermal movements and dead and live loads in a northern climate. Jointless bridges -- also known as integral abutment bridges -- have a superstructure that is cast integrally with the substructure, eliminating costly expansion joints and bearings. The project, Performance Monitoring of Jointless Bridges, is designed to provide VTrans engineers with the knowledge and quantitative data to design and construct cost-effective, safe, reliable, and low-maintenance structures.
|This bridge in East Montpelier, VT, is part of ongoing research to establish design guidelines for integral abutment bridges.|
The American Association of State Highway and Transportation Officials offers no specific guidelines for integral abutment design, so VTrans engineers have struggled with how best to approach the design of jointless bridges. Over the past 10 years, the agency constructed several of these structures based on perceived advantages such as reduced maintenance and construction costs compared to conventional abutment bridges.
According to VTrans officials, the research, which started in 2002 and runs through 2013, already is providing valuable insights. VTrans has used preliminary research results to refine construction details and specifications. Based on the agency's experience, current benefits of jointless bridges include reduced construction costs and fewer environmental impacts. In the long term, VTrans expects its research to lead to the development of comprehensive design standards with an overall goal of producing efficient, sustainable, and lower cost structures.
For more information, see http://onlinepubs.trb.org/onlinepubs/trnews/trnews267rpo.pdf or contact Chad A. Allen, VTrans quality engineer, at 802-828-6924 or email@example.com.
Transportation Research Board
FHWA recently updated its policy regarding the integration of Value Engineering (VE) in the Federal-aid highway program. VE is a systematic process of reviewing and analyzing a project during the concept and design phases with the help of an independent, multidisciplinary team of experts. The goals are to offer recommendations for providing the needed functions safely, reliably, efficiently, and at the lowest overall cost; to improve the value and quality of the project; and to reduce the time to complete the project.
Effective May 25, 2010, the new directive updates FHWA policy to clarify the requirements for conducting VE analyses and further identify the characteristics of the VE process, including life-cycle cost analyses. The policy also aims to influence when VE analyses are conducted to maximize their effectiveness, provide more consistent documentation of the analyses, and delineate responsibilities for establishing and sustaining VE programs to ensure that recommendations receive proper review, approval, and implementation. Lastly, the updated directive reflects changes to ensure the appropriate level of FHWA involvement, monitoring, and oversight.
For more information, visit www.fhwa.dot.gov/legsregs/directives/orders/13111a.htm.
USDOT recently released a report that analyzes a number of strategies the transportation industry can implement to reduce greenhouse gas (GHG) emissions. Strategies include using low-carbon fuels, increasing vehicle fuel economy, improving system efficiency, and reducing travel that involves high levels of carbon emissions. The report, Transportation's Role in Reducing U.S. Greenhouse Gas Emissions, Volume 1: Synthesis Report, discusses policy options for implementing these strategies, such as efficiency standards, transportation planning and investment, market-based incentives, research and development, and economywide carbon policies.
According to the report, burning fossil fuels to power U.S. vehicles causes 29 percent of all U.S. GHG emissions and 5 percent of global emissions. The majority of these emissions -- 59 percent -- come from light-duty vehicles, followed by freight trucks at 19 percent and commercial aircraft at 12 percent. Between 1990 and 2006, GHG emissions from U.S. transportation increased 27 percent and accounted for almost one-half of the total national increase during that period.
The report discusses specific strategies for cutting emissions, such as reducing the number of vehicle miles traveled by improving public transportation, coordinating transportation and land use strategies, and providing more opportunities for walking and bicycling. These strategies could help reduce transportation GHG emissions 5-17 percent by 2030.
For more information and to download the report, visit http://ntl.bts.gov/lib/32000/32700/32779/DOT_Climate_Change_Report_-_April_2010_-_Volume_1_and_2.pdf.
The Alliance for Biking & Walking recently released a benchmarking report that includes data on bicycling and walking demographics from all 50 States and the 51 largest U.S. cities. The report ranks the States and cities based on a number of indicators, including safety, policies and provisions, funding, staffing levels, infrastructure, bike-transit integration, education and encouragement activities, and public health indicators.
The report, titled Bicycling and Walking in the United States: 2010 Benchmarking Report, also highlights the connection between biking and walking and public health: States with the lowest levels of biking and walking have, on average, the highest rates of obesity, diabetes, and high blood pressure. In contrast, States with the highest levels of biking and walking have, on average, the lowest rates.
For more information and to download the report, visit www.peoplepoweredmovement.org/benchmarking.
Alliance for Biking & Walking
In 2008, FHWA established the Carbon Sequestration Pilot Program to explore the feasibility of State DOTs reducing and sequestering GHG emissions in vegetation within highway rights-of-way (ROW). In the report, Estimated Land Available for Carbon Sequestration in the National Highway System, FHWA estimates the amount of unpaved National Highway System (NHS) ROW available for carbon sequestration.
The report estimates that approximately 5 million acres (2.02 million hectares) of NHS ROW exist nationwide, and approximately 68 percent are unpaved. The report also estimates the NHS ROW has approximately 91 million metric tons (MMT) of carbon currently sequestered in vegetation and currently is sequestering approximately 3.6 MMT of carbon per year, or 1.06 metric tons of carbon per acre per year. This equals the annual carbon dioxide emissions of approximately 2.6 million passenger cars.
Current results show that even under the best scenarios, revenue generated from biological carbon sequestration varies greatly from State to State based on carbon prices, management techniques, and ecological variability. However, considering the use of vegetation for living snow fences, landslide minimization, and other such human infrastructure protection may, in some cases, be more cost effective than traditional engineering solutions.
In addition to this report, FHWA developed a Highway Carbon Sequestration Estimator to help DOTs assess the return on investment for various carbon sequestration scenarios. The tool, which enables transportation officials to make estimates based on State-specific considerations, is available from Carson Poe at firstname.lastname@example.org.
For more information, visit www.fhwa.dot.gov/hep/climate/carbon_sequestration/index.htm.
Five engineers from the Kuwait Ministry of Public Works recently attended TxDOT training on highway design, maintenance, pavement management, megaprojects, construction, and bridges. The training is part of a partnership, facilitated by FHWA, between the Kuwait Ministry of Public Works and TxDOT. Under the agreement, Ministry of Public Works personnel travel to Texas to receive on-the-job training and attend career development courses.
|Kuwaiti engineers meet with TxDOT professionals during a training session earlier this year in Texas.|
The Kuwaiti participants, who attended the training in Austin, TX, learned about materials testing equipment and bidding, inspection, and contract management issues. To cover a range of participant interests, the group divided into two subgroups at one point during the training. One subgroup spent its time with the TxDOT pavement management staff. The other subgroup met with TxDOT design professionals to hear about the department's design standards and processes.
Participants also discussed construction, inspection, and maintenance of bridges, with special emphasis on water table issues, cracking, and expansion joints. A portion of the training included a field trip to the University of Texas at Austin's Ferguson Structural Engineering Laboratory, which conducts bridge testing.
The training culminated with discussions on ROW and utilities, and a visit to the TxDOT Traffic Operations Division, where participants received information on highway safety and traffic management. The Ministry of Public Works hopes to implement in Kuwait some of the items learned during the training, such as design standards and processes, and inspection of steel bridges, which the Kuwaitis were particularly interested in.
New data from FHWA's 2009 National Household Travel Survey show that both bicycling and walking trips have increased by 25 percent since 2001. The Pedestrian and Bicycle Information Center included these data in The National Bicycling and Walking Study: 15-Year Status Report, funded by FHWA. The report details trends and changes in bicycling and walking since 1994.
The report finds that the estimated number of reported walking trips has more than doubled, from 18 billion in 1990 to 42.5 billion in 2009. Estimates for bicycling trips increased as well, from 1.7 billion to 4 billion during the same period. Although the percentage increase in bicycle and pedestrian trips fell short of USDOT's goal set in 1994, the report notes that the population increase resulted in a greater number of overall trips.
The report also found that from 1993 to 2008 bicycle fatalities decreased by 22.3 percent and injuries by 14.7 percent. Pedestrian fatalities dropped by 12 percent and injuries by 17.8 percent, surpassing the goal set in 1994. However, in 2008, there were still 4,378 pedestrians and 716 bicyclists killed in roadway crashes, indicating a need to continue to make walking and bicycling safer and more convenient transportation options.
The full report is available at www.walkinginfo.org/15_year_report.
The Oregon Department of Transportation recently examined the safety and benefits of motorcycle lane-sharing, sometimes referred to as lane-splitting or filtering, in the United States and overseas. The report, Motorcycle Lane-Sharing, details Oregon's literature review on the topic.
Although mostly prohibited in the United States, except in California, motorcycle lane-sharing is a common practice in many countries around the world. Lane-sharing enables motorcycles to take advantage of parts of the road not being utilized by allowing them to pass between lanes of stopped or slower-moving vehicles.
According to the report, benefits of lane-sharing include reducing overall congestion, potentially decreasing some types of motorcycle crashes, and in some cases, reducing motorcycle riders' travel times, creating an incentive for people to switch travel modes. However, the drawbacks include safety concerns due to motorcyclists being vulnerable to threats such as vehicles suddenly changing lanes or opening doors.
The report concludes that further analysis specifically on motorcycle lane-sharing is needed, and the authors suggest initiating pilot test studies and incorporating a lane-sharing variable into incident reporting as options for future research.
For more information, visit www.oregon.gov/ODOT/TD/TP_RES/docs/Reports/2010/Motorcycle_Lane_Sharing.pdf.
Oregon Department of Transportation
FHWA recently revamped the "Highways for LIFE" (HfL) Web site with enhanced content and an easier to navigate design. Accessible at www.fhwa.dot.gov/hfl, the site is a one-stop shop for information on the HfL initiative to accelerate widespread use of innovations in the highway community. The site's streamlined new home page features the program's latest developments and upcoming events, as well as links to success stories and information on innovations that speed construction, reduce congestion, and enhance safety and highway quality.
The site has several new features that ease navigation, such as one-click access from the home page to information on innovations, communications resources, technology partnerships, demonstration construction projects, and technology transfer tools. The site also includes information on related training, including the National Highway Institute's Innovations Web conference series and its technology deployment workshop and report, Leap Not Creep: Accelerating Innovation Implementation (FHWA-NHI-134073).
In addition, the revamped site offers "Inno-bits," which are brief, nontechnical descriptions of innovations in technology and management concepts, and "Driving Innovation!," a video on the challenges the highway community faces and how HfL is helping to address those challenges. The site also features demonstration projects, efforts to turn innovative prototypes into market-ready products, and articles and videos from FHWA and the highway industry on the latest innovation developments.