Scale model experiments on the insertion loss of wide and double barriers

The insertion loss of wide and double barriers is investigated through scale model experiments. Such configurations appear in outdoor sound propagation problems such as highway noise reduction and community noise control. The Biot-Tolstoy-Medwin (BTM) time domain wedge formulation for multiple diffraction [J. Acoust. Soc. Am. 72, 1005-1013 (1982)] is used to predict the acoustic response of an impulsive source. Evaluation of the insertion loss at discrete frequencies is accomplished via the fast Fourier transform (FFT). Good agreement has been found between the BTM model and experimental data for all configurations tested.