Noise-reflections on structures in the street (VSS2006/204)
Overview
Background & policy context:
Noise immissions are composed of the direct sound and reflections at buildings and structures. The reflections are difficult to calculate and so they are often disregarded. Acoustic measurements on scale models are usually too expensive.
For this reason the purpose of the project is to establish rules for calculating and judging the reflections for typical situations.
Objectives:
The research has focused on the following practical objectives:
- Show influence of reflections for different types and dimensions of structures such as underpasses, galleries, bridges, etc. on the intensity and characteristics of the decisive noise pollution
- Development of models to quantify the reflection shares
- Development of evaluation criteria for the arrangement and design of measures incl. Cost / benefit analysis (in particular for the lining with absorbent materials). It should be ensured the sustainability the noise.
The results of the tests are documented and the resulting findings should be simple and practically oriented applicable and form the basis for a standard.
Methodology:
To process the following sub-steps:
- Literature Study: Further evaluation of domestic and foreign studies as well as guidelines and standards on this subject
- Typing of buildings and definition of typical situations. The range of situations, which occurs in practice to be imaged, as well as possible with a limited number model types.
- Technical measurement of model situations by reference and comparative situations / evaluation of the frequency curves
- Mathematical simulation and model building with suitable programs (eg Cadna, Finite Differences-Time Domain Model of EMPA)
- Analysis and comparison of the metrological and theoretical studies and evaluation of the different influencing parameters (location immission, dimensions, materials, frequency content, etc.)
- Creation of measures with cost / benefit analysis, conclusions
- Development of evaluation criteria for the quantification of reflections and the assignment of model types and the application of measures
As a supplement is to be considered that future renovations, and possibly even new construction measurements before (without absorbing measures) and subsequently are to be taken (with absorbent linings). These can respectively by the cantons. Their agents are established. These measurements must be carried out (for reasons of time) outside the present research, however, could be included in a later revision of the results.
Share this page