Abstract
While the development of absorbing materials for barrier surfaces is attracting considerable research interest, relatively little effort is being devoted to modifying ground surfaces for optimum ground effect. Indeed current schemes for predicting outdoor noise levels due to transportation and industry distinguish only between two types of ground; acoustically hard and acoustically soft. Ground effect phenomena are described with reference to relevant laboratory and outdoor data which indicate the influences of surface characteristics including porosity, small-scale roughness, elasticity, vegetation, extended reaction, and topography. Theories for the propagation of curved wavefronts near to porous ground and above rough ground predict the existence of surface waves. The relationship between these waves is discussed. The robustness of ground effects to meteorological influences is considered. Optimum characteristics for porous pavement with regard to propagation effects are described. Other possibilities for passive noise control reviewed include deployment of rough pavements and poroelastic materials, modifications to railway ballast, roadside cultivation, and landscaping. [Work supported by EPSRC and BBSRC (UK).]
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
