LAUB

Due to a variety of positive effects (namely visual guidance, glare, wind and snow protection), vegetation verges alongside traffic routes are common. In regular time intervals, maintenance and safeguarding trims need to be conducted, whereat residents often report a worsening of the local noise situation. While the valid calculation method in Austria conservatively predicts noise attenuation only of more than 50 m of vegetation, this does not represent the subjective perception of the local residents. Therefore, the presented project aims at investigating the differences between individual impression and physical sound propagation calculations.

Therefore, an extensive measurement campaign in relevant acoustic situations was conducted and analyzed with regard to its technical and psychoacoustical parameters. Furthermore, a comprehensive listening test was carried out to describe the subjective perception of test persons due to variations in vegetation along the sound propagation path.

Based on the obtained results, a guideline is to be drawn up for the road operator, which – also in the light of the necessary safety aspects in the road area – makes it possible to optimally carry out the necessary maintenance and safeguarding trims for road users and local residents. For this purpose, a project-internal workshop with representatives of the client, acoustic and traffic safety experts from AIT as well as the respective PR departments was carried out in order to present these results to the desired extent in a publicly effective manner. The effects of vegetation are clearly detectable in the measurement as well as in the psycho acoustics tests.

With LAUB it was possible to analyze the noise exposure of the Austrian population taking into consideration technical, psychoacoustical and subjective aspects. Thereby, also the personal perception of residents was considered after maintenance and safeguarding trims of vegetation verges.