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4.3 Administrative and Institutional Changes In preparing to use the new procedures for pavement design, one of the biggest hurdles for most states is likely not to be technical but institutional. In most highway agencies, pavement design and traffic data collection and analysis are in separate areas. This separation limits interaction between these two groups and reduces the ability of the traffic data-collection group to adopt procedures that satisfy the changing input requirements of pavement design and that meet other needs of pavement designers. Most state highway agencies already collect the data needed for estimating traffic loads for mechanistic design. However, few agencies currently summarize this information and effec- tively report it to their pavement designers. As a consequence, few pavement design groups actually use much of the load data being collected. If the mechanistic design practices are to be implemented effectively, these failings must be remedied. The key to improving the collection of load data and its conversion into effective inputs for the mechanistic design procedures is a substantial increase in the interaction between pave- ment designers and the traffic data-collection and analysis staff. This interaction should include the following: Training for pavement designers on What traffic data are needed, Why those data are important, What effect the data have on the resulting pavement designs, Where to get the data that are collected, How to request more data when the available data do not meet design requirements, and How to review the traffic estimates being provided. Training for data-collection and analysis staff on What data are important for pavement design and what data have the largest effect on pavement design, How the data collected are used in the design process, and What the flow of traffic load data is in the pavement design process. Increased communication that Allows data-collection staff to correctly anticipate (and schedule) the data needs of the designers, 2-52

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Ensures that the data and summary statistics produced by the data-collection staff meet the needs of the pavement designers, Ensures that the data required are transmitted to the pavement design staff in a timely fashion and in a format that can be easily loaded into the mechanistic design soft- ware, and Involves both pavement design and data-collection staff in the review and refinement of the data-collection and summarization process used to feed the design process. (For example, are the Truck Weight Road Groups correctly defined? If not, how should they be revised? Where should additional truck weight data be collected? What other holes in the available traffic data should be remedied?) Reviews of The resources that are spent collecting traffic data, The relative value to the pavement designers of the various resources, and The potential value to the pavement program of addition expenditures on data collection. Although state highway agencies are already doing much of what is needed to meet the traf- fic data requirements of mechanistic pavement design, considerable work is still required to refine the existing procedures and software. Although data are collected, they often are not adequately summarized and reported. Resources will be needed to address these deficiencies. Resources are traditionally in very short supply for traffic data collection and analysis, and it will be necessary for the pavement design group to lend political support to the data-collection group if those resources are to be obtained. This will only happen if the pavement design group understands the importance of the traffic load data and if the traffic data-collection group can be relied on to provide those load estimates in a responsive and efficient manner. Neither of these conditions is currently met in very many highway agencies. The recommended increases in both communication and training should result in many improvements in both data-collection and pavement design processes. Fostering effective communication between the data-collection team and the pavement design group should result in traffic data-collection decisions that consider the needs of the pavement designers more effectively. Similarly, improved communication will enable pavement designers to use traffic data more effectively, thus allowing the development of more reliable designs. 2-53