Noise prediction models to determine the effect of barriers placed alongside railway lines

This paper is a survey of 14 models for predicting the effect of placing a noise barrier alongside a railway line. The prediction models are compared with each other and with various measurements. The individual methods of calculation employed reveal differences in the acoustical and geometrical characterization of the noise source(s) involved. A wide range of source locations is specified. Furthermore, calculations relating to attenuation by a barrier and to the effect of ground absorption utilize a variety of mathematical formulae. The insertion loss of a two m high absorptive barrier placed alongside a two-track railway varies between approximately 7 and 12 dB(A). For the nearer track, results vary between 8 and 15 dB(A), a range of 7 dB(A). (C) 1996 Academic Press Limited