FHWA Presents Technical Assistance Workshop in Nanjing, China
The City of Shanghai
Our safety on the Nation's roads can often be compromised over time as pavement begins to wear and perform poorly. In fact, more than $20 billion in Federal funds are spent by transportation agencies each year to maintain and improve the Nation's roads. But thanks to Mechanistic-Empirical Pavement Design, we can increasingly find ourselves less in danger of the poor performance as this technology contributes to longer life cycles for pavements and cost savings to users. Essentially, mechanistic-empirical pavement is an analysis tool that allows engineers to better understand pavement performance and create more reliable pavement designs. As this technology begins to be deployed across America, the Federal Highway Administration (FHWA) has encouraged States to evaluate the utility that the Mechanistic-Empirical Design Guide (M-E DG) provides and to carefully implement the guidelines and recommendations. Recently, this Guide crossed international boundaries as it was showcased at the Introduction to Mechanistic-Empirical Design Guide Workshop in Nanjing, China.
In April 2005, the FHWA Resource Center staff was invited to present the workshop during a special session organized by the Jiangsu Transportation Research Institute. As one of the Institute's goals to advance highway engineering in China, Monte Symons, FHWA Pavement and Materials Technical Service Team Leader, and Keith Herbold, FHWA Pavement and Materials Technical Service Team Pavement Engineer, served as "expert visitors" to present an expanded version of the team's standard 1-day workshop to about 130 attendees on the M-E DG, materials test information, and life-cycle cost analysis.
What is the M-E DG?
In spring 2004, the National Cooperative Highway Research Program (NCHRP) released the Mechanistic-Empirical Design Guide for New and Rehabilitated Pavement Structures. The guide provides uniform guidelines for designing common features of flexible, rigid, and composite pavements. Targeted to pavement engineers, the guide can be used to analyze and predict pavement distress including fatigue, rutting, thermal cracking in asphalt pavements, and cracking and faulting in concrete pavements. It also offers recommendations for evaluating existing pavements and recommendations for rehabilitation treatments, drainage, and foundation improvements. The Design Guide Implementation Team (DGIT) As major deployment of the M-E DG will take an estimated 5 to 8 years, the FHWA organized a Design Guide Implementation Team (DGIT) in 2004 to immediately begin the process of informing, educating, and assisting the FHWA's field offices, State highway agencies, industry, and others about the Guide. Along with its 13 Introductory Workshop initiative, DGIT has established a Lead States Group consisting of representatives from 15 States. The goal of this group is to promote and facilitate the refinement, implementation, and evolution of Mechanistic-Empirical Pavement Design procedures in conjunction with AASHTO, NCHRP, and FHWA activities. As the team continues its efforts to deploy the guide, several Materials Input Workshops are being offered throughout the year. The next workshop is scheduled for July 7-8 in Lincoln, Nebraska. To learn more about M-E DG and DGIT, please visit: Design Guide Implementation Team (DGIT)
Though asked to present at the Institute, the expert visitors made the most of their time by accepting an invitation to tour the southeastern portion of China to experience its highway transportation network along the cities of Beijing, Jiaxing, Hangzhou, Nanjing, Shanghai, and Suzhou. Symons and Herbold reported that an abundance of the construction in the region was ongoing within its rural expressways and toll roads, and very little pavement distress could be seen on major roads. In the major urban areas, traffic flow was inhibited by crowded streets with cars, buses, taxis, mopeds, bicycles, pedestrians, and just about every conceivable means of transportation moving along the roadway.
Though it may be years before Chinese provinces can incorporate mechanic-empirical design practices into its transportation industry, the success of this exchange will be seen in the future. As the trip was summarized by Symons, "They have made great strides but much remains to be accomplished. We consider this effort to be one of 'planting the seed' for future use." Overall, the FHWA Pavement and Materials Technical Service Team will continue to be a resource for technical assistance to the Jiangsu Transportation Research Institute and has already recommended a direct contact to provide training, specification and testing advice, and field observations for superpave asphalt mixtures in the near future.
In moving forward with the team mission—to advance the use of transportation technologies through training and technical assistance—the Pavement and Materials Technical Service Team will provide national and international assistance to deploy new technologies. On April 18, Monte Symons, Keith Herbold, and Jim Walls (Pavement Design Engineer) presented the M-E DG workshop to 60 professionals from all over Canada at a workshop sponsored by the Transportation Association of Canada.
To gain more information on
training and technical assistance
offered by the Pavement and Materials
Technical Service Team, you can
visit the FHWA Resource Center
For more information, contact:
Monte Symons, P.E.
Pavement and Materials Technical Service Team Leader
FHWA Resource Center