Improvement of impact sound insulation: A constitutive model for floating floors

Floating floors have a high potential for reducing disturbance by impact noises in dwellings, since it greatly reduces the vibrations transmission through structures. The acoustical performance of a floating floor is quantified in terms of improvement of impact sound insulation ΔL. The improvement of impact sound insulation of a floating floor is a key parameter for the calculation of structure-borne sound insulation in buildings. Indeed, once ΔL is known, it is possible to evaluate the impact sound insulation, in in situ conditions, for several base floors of different building technologies and materials. ΔL can be directly determined on the basis of standard laboratory measurements, but it can be also estimated from elastic and inertial properties of involved materials, such as stiffness and mass. In this paper a constitutive model for the estimation of floating floors improvement of impact sound insulation is presented. As it will be shown, the constitutive model proposed based on force transmissibility theory, allows to accurately estimate the acoustical behavior of a floating floor, as a function of frequency, with a simple single function. Theoretical assumptions, experimental evidences and comparisons with previous computational models (e.g., Cremer-Vér model) allow to confirm both validity and effectiveness of the proposed model.