Tire-pavement noise: An investigation of its importance in mitigating highway noise impacts

Highway traffic noise is a complex phenomenon which is the result of the combined effects of the various emission sources present on a moving vehicle. With changes in the nature and strength of these individual sources, the prediction of noise levels at a wayside receiver is made significantly more complex. Existing noise emission models do not specifically account for the effect of the changes that occur in each of these individual sources. It is hypothesized that discrepancies between predicted and actual observed levels are experienced in certain cases due to the lack of sensitivity to individual source strengths.; The new Federal Highway Administration (FHWA) Traffic Noise Model (TNM) which has recently been released does address some of these variations in specific sources including some effect of different pavement types.; The purpose of this dissertation is to investigate the “tire noise” component of highway noise and to develop a methodology and an accompanying procedure for evaluating the effects of changes in individual source characteristics on resulting wayside noise levels. The dissertation discusses existing prediction models, describes some of the tire and pavement combinations investigated and presents a procedure for tire-pavement noise assessment. Although the procedure is developed to be sensitive to all sources, the major emphasis is on tire noise and the completion of sensitivity analysis with respect to changes in such aspects as tire type, pavement type, and vehicle mix and speed. A series of possible applications is presented to show the potential usefulness of the procedure.; In the course of the development of this procedure, it was necessary to make significant advancements in the highway noise measurement techniques. Thus, a system was developed for this purpose which results in the level of detail necessary for carrying out this procedure and the associated sensitivity analyses. The measurement techniques and equipment described briefly in this dissertation were developed by the author under the guidance of his dissertation advisors, and in conjunction with previous research completed for the Federal Highway Administration.