Prediction of Road Traffic Noise

A computer model for the prediction of noise from freely flowing road traffice is described. The model allows one to account for simple statistics of point sources (spatial distribution and radiated sound power) and for sound propagation with attenuation, diffraction, and reflection. The basic statistical parameters of the fluctuating noise calculated at a receiver are the cumulants of the sound intensity. These cumulants are employed to calculate probability distributions of the SPL as well as single number criteria currently used for the description of fluctuating road traffic noise. The computer model has been developed for the Transportation Systems Center, Cambridge, Massachusetts.