When predicting the performance of noise barriers, vehicles are too often considered as point or line sources, neglecting their motion, body and reflective sides. Using sound absorbtive materials helps to reduce the sound reflections between vehicle body and noise barriers, and the interaction phenomenon is generally neglected. For reflective barriers, by contrast, this phenomenon is severe. Even when dealing with absorbtive barriers, for example, when they are close to the vehicles, the multiple reflections phenomenon becomes more important and can lead to a degradation of performance. Several designs can be considered in order to reduce these multiple reflections, e.g. absorbing materials, and inclined barriers. Even with classical sound absorbing materials, though reduced, these reflections can degrade the performance of barriers. One should consider this effect for the accurate design of barriers (materials and forms); 4D (3D+time) models are more appropriate and one should avoid to consider moving vehicles as fixed sources of coherent noise. Further investigations could be done with diffuse models for reflections instead of specular ones, or even a combination of the 2 effects.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    How multiple reflections can a degradation of performance for noise barriers


    Additional title:

    Wie Mehrfachreflexionen eine Verminderung der Wirkung von Lärmschutzwänden verursachen können


    Contributors:
    Clairbois, J.P. (author) / Houtave, P. (author) / Trefois, V. (author)


    Publication date :

    1996


    Size :

    6 Seiten, 4 Bilder, 1 Tabelle, 7 Quellen



    Type of media :

    Conference paper


    Type of material :

    Print


    Language :

    English




    The performance of multiple noise barriers

    Crombie, D.H. | Online Contents | 1994



    Reflections from Highway Noise Barriers and Use of Absorptive Materials in the United States

    Menge, Christopher W. / Barrett, Douglas E. | Transportation Research Record | 2011


    Acoustic performance of the M6 noise barriers

    Nelson,P.M. / Abbott,P.G. / Salvidge,A.C. et al. | Automotive engineering | 1976


    Highway noise barriers

    Cohn, Louis F. | TIBKAT | 1981