Аннотация:This article presents the results of vehicle noise measurements in ten key sites in Moscow in 2019 with dissected meso- and microrelief of the terrain. The measurements were carried out synchronously near the road and at different distances from it, at breakpoints of the hypsometric profile. Paired measurements made it possible to estimate the amount of traffic noise damping (reduction). At the same time, noise suppression was determined instrumentally and verified by computer simulation for a subhorizontal surface. All of this made it possible to assess the influence of the ground surface on traffic noise propagation. This effect is estimated at values of up to 17 dBA (sound damping based on the noise protection function of the relief). A number of profiles exhibited an increase in the noise level as a result of the accumulation effect, i.e., when the relief facets facing the noise source return sound energy that was not absorbed by the surface and increase the noise level relative to the nominal level (for subhorizontal surfaces) by 2–4 dBA. However, the influence of the relief is mostly reducing and has average damping rates of 5 dBA throughout the profile length (40– 120 m in different cases), regardless of the shape of a specific profile. It is shown that statistically significant differences in the noise level of about 1.5 dBA above the error of sound level meters on convex surface inflections (terrain edges and ridges) are observed even at the level of submeter elevation differences. At the same time, the more dissected the ground surface near the road (a few dozens of meters), the more significant the influence of the relief. At a distance of about 150 m, the role of an individual sound source in the urban environment becomes so negligible that it makes no sense to assess the influence of the relief on this source.
