Extension of weather influence modeling of ground acoustic properties to various ground surface types

In our previous work, the influence of weather on the acoustic properties of a sandy ground surface has been modeled based on a long-term in-situ measurement campaign of meteorological elements, water saturation of soil and ground acoustic properties [Kurosaka et al., Noise Control Engr. J. 66 (6), 505-522 (2018)]. The modeling strategy was to obtain the effective flow resistivity of the ground surface from observed meteorological elements by way of water saturation of soil. In this work, the effort is extended to four ground surface types: farmland, grassland, rice field, and compacted soil ground. The modeling strategy is same as the previous work, but the employed measurement method of the acoustic properties has been changed from the ensemble averaging (EA) method to a more stable method based on the well-known ANSI/ASA S1.18-2010 standard. The results show that the model fits well to the farmland, the grassland and the rice field with a good relation between the water saturation and the effective flow resistivity. By contrast, the model does not fit well to the compacted soil ground because only a poor relation is found between the water saturation and the effective flow resistivity.