Optimisation of acoustic surfaces (Noise barriers)

The new international procedure to measure and evaluate noise barriers is called “prEN 1793-5, „Adrienne-method“. This procedure encompasses the assessment of surfaces, the use of materials, the on-site efficiency and the long term behaviour. Currently models for noise protection as well as noise barriers focus on propagation calculations. However they fail to take into account new developments in noise barriers (tops, solar panels, etc). The Mobility Department surveys these new developments and in order to optimise and implement advancements in prognosis and calculation.

The precious research projects show a strong dependency from the absorption property of noise barriers to the surface designs and material properties. Potentials for optimisation are of great interest for the producers of noise barriers.

We aim to recalibrate the Adrienne-method for the purpose of improving the absorption of noise barriers. The Adrienne method originates in a research project developing on-site measuring methods for sound absorption and insulation. This method to determine sound absorption (according to CEN/TS 1793-5) distinguishes between reflected or passed sound as they encounter noise protection elements. Our goal is to create universal applicability on roadways with heavy traffic. The site-specific installation of noise barriers and possibility of log-term surveys remain actual goals.

Another alternative to improve the noise situation is the frequency dependent control of multifunctional noise barriers. In the context of a research project the implementation of more efficient plant controls is examined in regards of conversion. Alternatively a frequency dependent travel regulation based on a noise calculation model - under consideration of various surrounding factors- is being examined.