Investigation of the effects of different types of interlayers on floor impact sound insulation in box-frame reinforced concrete structures

• Damping materials provide a higher loss factor and stiffness than other interlayers.
• Impact vibration at low frequencies is decreased owing to damping materials.
• Damping material is effective to reduce the heavyweight impact sounds.

In the present study, the effects of resilient isolators and viscoelastic damping materials on reducing heavyweight floor impact sounds from reinforced concrete structures were investigated using FEM simulations and in situ measurements. At first, the dynamic properties of the materials were measured using a beam transfer function method to include the properties in an FEM simulation. As a result, the damping materials provided a higher loss factor and dynamic elastic modulus than the resilient isolators. Subsequently, FEM simulations and in situ measurements were conducted to investigate the effects of the interlayers on the characteristics of floor impact sounds and vibrations. The results indicated that the impact vibration acceleration level and floor impact sounds at low frequencies were significantly decreased owing to the installation of damping materials, whereas the impact sound pressure levels at low frequencies were increased as a result of the use of resilient isolators.