Measuring and modeling tire-pavement noise on various concrete pavement textures

It is well accepted that pavement texture affects tire-pavement noise. Furthermore, there exist a large number of unique nominal concrete pavement textures to choose from, and with tire-pavement noise an important pavement surface characteristic, pressure now exists to select textures that are quieter but do not compromise safety and to some degree, durability. To assist in this optimization process, improvements are needed in the efficiency and accuracy of texture measurement, along with the means to characterize concrete pavement texture in such a way that is more relevant to the potential for tire-pavement noise. To illustrate improvements being made in measurement technology, an innovative robotic texture measurement system termed RoboTex is described herein. RoboTex consists of a line laser machine vision sensor fixed atop a remote-controlled robotic chassis. The system is capable of collecting three-dimensional macrotexture data with a spatial resolution of approximately 0.4 mm(2) and a height resolution of 0.01 mm. For tire-pavement noise measurement, On-Board Sound Intensity (OBSI) has become the de facto measurement standard in the USA. While most measurements to date have been conducted at 60 mph using a Goodyear Aquatred III test tire, recent standardization is migrating towards the new ASTM F 2493 Standard Reference Test Tire (SRTT). Coupling texture and noise data, collected with RoboTex and OBSI, respectively, is serving to advance the state of the art. The ultimate goal is to identify the fundamental links between texture and noise. In the interim, more relevant phenomenological links are sought that have the potential to be expanded to more fundamental models as more is learned about these complex phenomena. This project utilized data collected on over 1000 unique concrete pavement test sections located throughout North America under sponsorship of the National Concrete Pavement Technology Center at Iowa State University, Federal Highway Administration, American Concrete Pavement Association, and now a consortium of State Departments of Transportation. The specifics of these measurement systems, and analysis techniques used to link the results, are described herein. (C) 2009 Institute of Noise Control Engineering.