Functional properties are recognized today as critical elements of pavement performance and management. In addition to structural and durability requirements, an optimum pavement wearing surface should provide a combination of low roughness, good friction and macrotexture (splash/spray), and low levels of noise. All these properties are highly influenced by the various components of the pavement surface texture. The way the various components of pavement texture impact functional service is better understood now. For example, micro-texture (features less than 0.5-mm in length) is most relevant to low-speed friction while mega-texture (50-mm to 0.5-m in length) means more to tire damage and in-vehicle noise. However, there are many practical questions that remain unanswered. Some of these relevant questions include: · What are the best methods and equipment for measuring pavement surface texture? · How accurate, repeatable and reproducible are these methods? Is there a need for harmonization exercises? · What environmental-related factors have to be considered during the measurements? Are corrections to the measurements necessary? · What are the most promising emerging technologies, and how should these technologies be tested? · Is it possible to define ¿optimal¿ levels of texture for different types of roads and traffic levels? If so, what are the tradeoffs involved in this selection? · Can changes in pavement surface texture with traffic, environment, and time be modeled and forecasted? · What are the required and desired targets for the various properties under consideration? · What surface texture requirements can/should be specified for construction quality control and assurance and/or pavement warranty contracts?

The objective of the proposed pool fund is to establish a research program focused on enhancing the level of service provided by the roadway transportation system through optimized pavement surface texture characteristics. The initial focus of the program will be the application of inertial and laser-based equipment for measuring these properties. Other questions and issues will be identified in cooperation with the pool fund participants. An interactive project solicitation process will be used to request feedback from all participants.

The five-year program will be developed in cooperation with the consortium participants and will include at least the following: · Establishment of a comparison/verification facility for elevation profile and texture. This facility will be set up at the Virginia Smart Road, which includes a variety of ¿real world¿ flexible and rigid surfaces and offers very convenient and controlled conditions. · One equipment comparison/verification ¿round up¿ per year at the Smart Road. These would be open to all pool-fund participants (free of charge). Reference elevation profile and texture measurements will be established and provided to all participants. · Evaluate new and existing methods and technologies for measurement of pavement surface properties. · Coordinate and organize international harmonization studies as needed. · Conduct specific studies that require measurement of pavement surface properties under a controlled traffic and/or environment on different types of road surfaces, as determined by the pool fund participants. · Organize and deliver Continuing Education courses and workshops to explain the importance of pavement surface properties and the technologies and methods used to measure them.

This project is expected to serve mostly the eastern region of the country with an estimated participation of at least eight members. The Virginia DOT, as the host organization, is committing a partially dedicated researcher plus $20,000 annually to cover setup and operational expenses for the facility. A variable fee depending on the participant¿s affiliation and interests may be appropriate. Initial estimates suggest that an annual fee of $20,000 for federal and state agencies and $10,000 for local agencies, consultant, and equipment manufacturers. The previous sections presented several potential high-payoff high-impact research topics. However, it is anticipated that the consortium will focus on those projects that are most relevant to its participants. Thus, the first activity of the consortium will be a workshop for the participants to discuss research needs and prioritize the identified projects (travel costs to be covered by pooled fund).