Using On-Board Sound Intensity (OBSI) for Other Purposes

摘要

The use of On-Board Sound Intensity (OBSI) has become a useable tool to rank the sound created at the tire/pavement interface for pavement textures. The changes in the different pavement textures, both rigid and non-rigid pavement, result in both amplitude and frequency changes at the tire/pavement interface. Measurements using OBSI are accomplished on a moving vehicle at the tire/pavement contact point. The use of intensity methodology allows this measurement to be accomplished even in heavy traffic. The results of the measurements allow various pavement textures to be selected based on noise control although safety and durability must also be considered. However, the same ranking does not always occur at the wayside where the human activity is located. This paper shows how these rankings can vary based on recent work in Florida and discusses the reasons this occurs. It also shows how work is underway to develop a way to predict wayside noise from OBSI measurements based on common pavement tests. This problem has long existed and needs to be quantified. For too long analysts have assumed the OBSI levels and reduction due to pavement texture selected are equivalent to the wayside noise reduction. This makes this paper both timely and needed as the research is beginning and progresses. The paper also introduces the concept of OBSI which is a relatively new area of noise analysis. Results from the Florida measurements, both OBSI and wayside in matched pairs, will be shown to support the ideas presented as well as the differences between OBSI and wayside measurements. Variance in amplitude as well as frequency will be highlighted in the paper.