Vibration reduction index improvement by adding resilient strips: influence of junction properties

Resilient strips can be used to decrease the structural transmission in junctions and thus limit the flanking sound transmission in buildings. In the standard ISO 12354-1, the efficiency of a resilient strip is characterized by the vibration reduction index improvement. To evaluate the vibration reduction improvement, a standardized measurement method is needed. However, the vibration reduction improvement is not an intrinsic material parameter of the resilient strip and can depend on the mounting conditions and junction geometry. In this paper, the vibration reduction index improvement is evaluated by means of numerical simulations carried out with a statistical model for junctions with resilient strips. The model was first validated by laboratory measurements. While the influence of the junction type (L, T or X) and transmission path (straight on or around the corner) is limited, the influence of the plate properties (mass and bending stiffness) cannot be neglected, with differences in vibration reduction improvement of up to 20 dB.