Experimental approach on natural frequency of window vibration induced by low frequency sounds

Low frequency sound may cause environmental problems such as window rattling and human feeling indoors. In previous studies, we conducted field experiments to investigate transmission of low frequency sound into a test building by using a transportable device that could generate low frequency sounds down to 2 Hz. Results showed that windows of the test building vibrate easily at around 12 Hz. However the reason has not been clarified. In this study, we conducted a field experiment in which we used same test building and same low frequency sound source to verify the spring-mass system model, by supposing windows to be mass and air inside the room to be spring. Results show, natural frequency of window vibration is not only affected by the factor of the spring-mass system, but may also be affected by the factor of stiffness and air-tightness of windows.