A comparison of sound and impact transmission through structures with different natural frequencies

Transmission loss through double panel systems is typically understood to be correlated with the mass of the two panels and the distance between them. This does not take into account the rigidity of the structure supporting the panels or other characteristics of a floor-ceiling system that may affect sound transmission. While it has been anecdotally observed that longer-span structures have lower transmissionloss than similar floor-ceiling assemblies with shorter spans in buildings, disentangling other important variables such as construction quality or flanking through adjacent building elements is difficult. While lab tests remove many of those variables, previous studies have been limited by the size of the test openings to only compare small changes in span length. An experiment was designed to simulate span length by varying the natural frequency of the structural system. From this study, we hope to show whether and how much the stiffness of the structure contributes to the sound and impact transmission loss of a floor-ceiling assembly.