Experimental and numerical study on the propagation of impulsive sound around buildings and induced structural loading

Abstract

Propagation of impulsive sound around buildings and induced structural loading are investigated experimentally and numerically. Experiments were conducted on a rectangular building at Virginia Tech using sonic booms generated by an explosive technique. Assuming linear-acoustic propagation and acoustically rigid surfaces, these experiments were simulated with a three-dimensional numerical model, in the context of geometrical acoustics, by combining the image source method for the reflected field (specular reflections) with the Biot-Tolstoy-Medwin method for the diffracted field. This numerical model is validated against a boundary element solution and against experimental data, showing a good overall agreement. Some of the key advantages of this modeling approach for this application are pointed out such as the ability to model three-dimensional domains over a wide frequency range and also to decompose the sound field into direct, reflected, and diffracted components, thus allowing a better understanding of the sound-propagation mechanisms. Finally, this validated numerical model is used to investigate sound propagation around a cluster of six rectangular buildings, for a range of elevated source positions.