Vibration identification and sound insulation of triple glazing

This paper presents the results of the experimental vibroacoustical and modal testing of a triple pane insulating glazing structure. The testing was performed in the sound transmission facility using acoustic excitation, force excitation and a laser scanning vibrometer for measurement of frequency response functions and volume velocity. The results of the identification include the modal mass, damping and stiffness, vibratory modes and volume velocity distribution. A new measurement method is presented in order to identify the global vibratory modes of all three combined transparent glass panes simultaneously. These results are essential for updating the analytical model of triple glazing for calculation and prediction of sound transmission loss over a wide frequency range. The calculated and measured sound transmission loss is presented and discussed.