a computer model for determining the temporal distribution of noise from road traffic

a new method is described for computing the temporal distribution of noise from freely flowing traffic, which is much faster than monte carlo models of similar sophistication. validation studies indicate that the standard deviation of the observed values from the computed values of l10, l50 and l90 are 1.1, 1.3 and 1.9 dba respectively. using the model, simple equations have been derived relating l10, l50 and l90 to the traffic flow, mean speed, proportion of lorries in the traffic stream and the distance from the roadway where the propagation is over grassland. the equations are designed primarily for traffic conditions beyond the range of applicability of existing prediction schemes yet are consistent with the conditions encountered in the majority of urban roadway networks. the computer model can be readily extended to synthesize traffic noise in urban roadway networks and, in principle, noise from different transport modes. it is intended to develop the modelling technique further to construct an urban noise model incorporating complex roadway networks and ultimately various transport modes. (a).