Abstract
A new light sound insulation structure which is constructed with pressurized light inflated membrane bound by hard wire nets (Membrane Sound Insulator: MSI) was proposed and proved to have high sound insulation performance especially in low and middle frequency region according to its high rigidity in the previous papers. Moreover the sound insulation performance of MSI can be tuned by its air pressure. In this paper, in order to develop the structure of practical use, some composite structure which has double light weight walls with MSI between them were manufactured and tested. As the results, MSI was proved to increase the sound insulation performance of double wall in the middle frequency region in which normal double wall with sound absorbing material between them had poor sound insulation performance. Moreover, a simulation model predicting the sound transmission loss of MSI was developed and proved to be useful for studying the configuration of MSI qualitatively.
