In its pursuit for providing smooth pavements, the Directorate General of Highways in Taiwan is developing and implementing ride quality specification as part of the construction assurance program. The straightedge and the profiler were used to measure pavement smoothness on 561 test sections. Probability distribution analysis showed that measurements of pavement smoothness of both devices follow the normal distribution. Smoothness specifications for construction quality control were developed for straightedge and profiler, respectively. The full-pay range is 1.36 to 2.45 mm and 2.16 to 3.65 m/km for straightedge and profiler, respectively. The smoothness relationship between straightedge and profiler was developed.

Nearly all State highway agencies use smoothness specifications to ensure that hot-mix asphalt (HMA) and portland cement concrete (PCC) pavements are built to high levels of smoothness. About half of all current State smoothness specifications for HMA and more then three-fourths of all current PCC smoothness specifications are centered around the Profile Index (PI), as often measured using a profilograph. The vast majority of these specifications utilize a 5-mm (0.2-in.) blanking band in computing PI (i.e., PI5-mm). Assistance in selecting appropriate IRI and PI0.0 specification limits is needed to provide a basis for modifying current specifications to these more reproducible and portable smoothness indices. This research effort has developed a series of relationships between IRI and PI that can assist States in transitioning to IRI or PI0.0 smoothness specification for HMA and PCC pavements.

"This new ASTM publication presents the latest information on the practical and developmental aspects of pavement surface evaluation procedures and technologies, including their reliability and relevancy. Seven peer-reviewed papers cover: * Pavement surface characteristics measurement procedures and equipment * Approaches to enhance the reliability and accuracy of pavement surface evaluation systems * Approaches to harmonization between different measurement devices for specific pavement surface condition indicators * Assessment of current pavement condition indicators and their relevancy level for use in asset management * Assessment of factors influencing the interaction of tire/pavement surface characteristics * Assessment of automated distress survey systems * Evaluation of new/promising technologies for pavement condition surveys."--Publisher's website.

This publication contains papers presented at a December 2001 symposium, focusing on hot mix asphalt (HMA) smoothness measurements, specifications, and equipment. Five papers provide insight into the development and implementation of roughness specifications for pavements, and two papers offer natio

This report describes: (1) investigation of time-sequence roughness data collected at GPS test sections to study trends in development of roughness, (2) comparison between International Roughness Index and Ride Number, (3) development of models to predict changes in roughness, (4) investigation of roughness characteristics of new flexible and rigid pavements built for the SPS program, (5) investigation of roughness characteristics of flexible and rigid pavements that were subjected to different rehabilitation strategies under the SPS program, and (6) recommendations for quality assurance and profiling frequency for the test sections.