The STAMINA 2.0 computer program is the most commonly used method for prediction of traffic noise levels for impact analysis and noise barrier design. However, the program was based on theory for freely flowing vehicles at a constant speed. The work presented in this paper represents development of a methodology to use STAMINA 2.0 in nonconstant speed situations, such as signalised intersections, intersections with stop signs, tollbooths, and highway loop and slip ramps. Through a review of literature and collection of new emission levels on accelerating, decelerating, and cruising heavy trucks, a data base was established for the methodology. The concept of zone of influence (ZOI) was used to represent stretches of road on which acceleration or deceleration occurs and on which sound levels may vary from cruise condition levels. Two series of equivalent constant speeds (one for acceleration, one for deceleration) were developed, permitting STAMINA 2.0 to calculate the desired difference in noise level relative to cruise on the basis of the findings of the literature review and field data analysis. Validation at two sites containing intersections produced results within 1 dB of predictions at all measurement points after refinement of the preliminary ZOI lengths and after calibration of the cruise predictions.
Abstract