Vibro-acoustic Characteristics of Box-Frame type Reinforced Concrete Floors and Control of Heavy-weight Floor Impact Sound Using Isolation Materials

Abstract

Resilient isolators and damping materials were tested in reinforced concrete high-rise apartment buildings, and their effects on reducing heavyweight floor impact noise compared. The use of visco-elastic damping materials increased natural frequency and decreased the vibration acceleration level. Heavy-weight impact sound levels below 80Hz decreased substantially with the use of these visco-elastic damping materials, whereas the sound levels in the structure increased in the same range with the use of resilient isolators. This was the result of energy absorption of the constrained damping layer and the adhesion properties of visco-elastic damping materials, which create a single body with the upper layers of the floor structure. Increasing the natural frequency of a floor structure effectively reduces sound levels from heavy-weight impact sources.