Correlation between dynamic stiffness of resilient materials and heavyweight impact sound reduction level

Installing resilient materials between the slab and the Ondol layer is known as the most popular method of reducing floor impact sound in Korean apartments. The Ondol layer is made up of lightweight concrete and mortar constructed on the upper part of the resilient material, and is a typical heating system used for all types of residential buildings in Korea. In Korea, lightweight impact sound and heavyweight impact sound are considered when evaluating the floor impact sound. The resilient materials used can be categorized according to dynamic stiffness. Resilient materials with a low dynamic stiffness reduce the lightweight floor impact sound level. In this study, to examine the relationship between dynamic stiffness and heavyweight impact sound level, the dynamic stiffness and floor impact sound level of 51 resilient materials were measured. The impact sound level of each of these resilient materials, whose dynamic stiffness was measured, was measured before and after installation, and the level difference (ΔL) was analyzed. The measurement results show that, if the dynamic stiffness of single-layered resilient materials is known, the dynamic stiffness of multi-layered structures of resilient materials can be predicted. Also, as the dynamic stiffness of resilient materials decreased, the heavyweight impact sound level also decreased, and there was a correlation between the dynamic stiffness and the heavyweight impact sound.