In its pursuit for providing smooth pavements, the Massachusetts Highway Department (MHD) is developing and implementing ride quality specifications as part of its construction quality assurance program. To achieve its goal, MHD, in cooperation with the Federal Highway Administration, sponsored a research project to identify suitable profiling devices with adequate precision and bias for implementing construction quality assurance specifications. The purpose was to evaluate precision and bias of profiling devices based on ASTM E950-94. In 1999, the study was conducted, wherein 16 profiling devices, including high-speed, lightweight, and walking profiling devices, performed 10 repeat runs on eight sites each. Analysis of precision (repeatability) with the international roughness index (IRI) shows that approximately 75% of all tests have an average standard deviation in IRI units below 0.05 mm/m (3 in./mi). The high-speed devices produce better results compared to the lightweight profilers with almost 90% of all tests producing a standard deviation below 0.05 mm/m (3 in./mi) IRI units. Analysis of bias (profiling device, Walking Profiler) with the IRI statistic shows that for all devices, 80% of the left wheelpath tests fall below a bias range of +/- 0.09 mm/m (6 in./mi) IRI units. Profile analysis and profile lead-in effect were also determined.
Abstract