Measurement of the radiation efficiency of suspended ceilings at low frequencies using swept sine excitation and high-frequency resolution
- It is common for timber ceiling constructions to include a suspended ceilings made of plasterboard. In order to minimize the radiation from impact excitation, especially in the low frequency range below 100 Hz, a detailed analysis of the vibration behaviour was necessary.
An experimental modal analysis was carried out and the radiated sound power from the suspended ceiling was measured using a sweep sine excitation by a shaker connected to the top layer of the timber floor construction.
Since the experimental modal analysis was conducted using a high frequency resolution and with a non-stationary sound field, it was necessary to check the validity of the intensity measurements by comparing it with 1/3-octave band measurements. The results show very good agreement.
By this means the radiation efficiency can be measured simultaneously with an experimental modal analysis of a structure.