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7 Roller-Mounted-Density/Stiffness Devices--Non-nuclear density and stiffness monitoring devices attached to the rollers (for example, the BOMAG Varicontrol and Onboard Measur- ing System) were excluded because these devices have not been extensively used for QC, few agencies are evaluating this technology for possible use in the future, and there are a limited number of these rollers available for contractor use. Although the roller-mounted devices were excluded from the field evaluation, the roller manufacturers were contacted to determine their availability for use on selected projects. Surface Condition Systems--None of the surface condition measuring systems or devices was suggested for further evaluation under NCHRP Project 10-65. Although the initial Interna- tional Roughness Index (IRI) is an input to the MEPDG, the smoothness measuring devices used for acceptance of the wearing surface are already included in the QA programs of many agencies. In addition, none of the devices provides an estimate of the volumetric and struc- tural properties of the wearing surface. Noise and Friction Methods--Noise and friction measuring devices were excluded from further consideration because these properties are not needed in the MEPDG or any other structural design procedure, and no agency is considering their use for acceptance. Infrared Tomography--Infrared cameras and sensors were excluded from the field evaluation because their output only provides supplemental information to current acceptance plans. In other words, the devices are used to identify "cold spots" or temperature anomalies. Other test methods are still used to determine whether the contractor has met the density specification. This statement does not imply that this technology should be abandoned or not used--the infrared cameras and sensors do provide good information and data on the consistency of the HMA being placed by the contractor. However, they do not provide information that is required for QA programs. Other Ultrasonic Test Methods--Impact echo and impulse response methods, as well as the ultrasonic scanners, were excluded because they are perceived to have a high risk of implementation into practical and effective QA operations. Continuous Deflection-Based Devices--Rolling wheel deflectometers that are under devel- opment were also excluded from the field evaluation. These devices are considered to be in the research and development stage and are not ready for immediate application into a QA program. Projects and Materials Included in the Field Evaluation The field evaluation was divided into two parts, referred to as Parts A and B. The primary purpose of the Part A field evaluation was to accept or reject the null hypothesis that a given NDT technology or device can accurately identify construction anomalies or physical differ- ences along a project. A secondary purpose of this part of the field evaluation was to confirm that the NDT device can be readily and effectively implemented into routine QA programs for flexible pavement construction and HMA overlays--an impact assessment. Part B of the field evaluation was to use those NDT technologies and devices selected from Part A and refine the test protocols and data interpretation procedures for judging the quality of flexible pavement construction. Part B also included identifying limitations and boundary conditions of selected NDT test methods. Table 3 lists the projects and materials included in the field evaluation, while Table 4 lists those defects and layer differences that should have an impact on the quality characteristics measured by the QA tests. Table 5 contains the anomalies and differences of unbound material sections placed along each project. Likewise, Table 6 lists the anomalies and differences of HMA layers. None of the NDT operators were advised of these anomalies or physical differences.