Evaluation of the long-term sound reduction performance of resilient materials in floating floor systems

• The long-term sound reduction performance of eight resilient materials was evaluated.
• The dynamic stiffness of the specimens was monitored for 270 days under two load conditions.
• Dynamic stiffness increased with time, leading to a decrease in sound reduction.
• Greater decrease in the sound reduction performance was found in soft materials.
• More rapid reduction in the dynamic stiffness was observed under a larger load.

Building multi-dwelling units is one of the practical engineering solutions to housing shortage in urban areas with high population density. However, noise from upstairs is a major issue. The use of resilient materials in floating floor structures is recognized as an effective method to reduce such noise. In general, soft materials are considered as better resilient materials due to their superior performance in impact sound reduction. However, it is often overlooked that the sound reduction performance of soft resilient materials is susceptible to being degraded over time when subjected to a long-term load. In this study, the long-term performance of eight resilient materials is evaluated by monitoring their dynamic stiffness for 270 days under the two sustained load conditions: 250 N and 500 N. According to the experimental study, the dynamic stiffness increases consistently with loading time for all resilient materials. This leads to a decrease in the sound reduction performance. More rapid reduction in the dynamic stiffness and hence in the sound reduction performance is observed when a larger sustained load is applied. A greater decrease in the sound reduction performance is found in soft resilient materials.