Abstract
To establish a relationship between the floor impact sound level and driving-point impedance, a floating floor built on a wooden floor was used in the laboratory. The results are as follows:
1. The floor-impact sound-level difference for cases with a rubber-ball impact source tends to be greater than that for those cases with a car-tire impact source.
2. The difference between the driving-point impedance levels of the surface material of the floating-floor system is practically identical to the floor-impact sound-level difference in cases with a rubber-ball impact source.
3. The driving-point impedance-level difference, the flexural-rigidity-level difference, and the surface-density-level difference were defined here, and the relationships with floor impact sound level differences were compared.
4. An accurate estimate for the flexural rigidity, which is used to calculate the driving-point impedance on the surface material of the floating-floor system, is the sum of the values calculated for the individual members.
5. A floor-impact sound-level difference of 10 dB or higher was achieved at a 63 Hz band when the driving-point impedance of the surface material of the floating-floor system was increased from 2,100 to 6,700 kg/s.
