A FUNDAMENTAL STUDY ON NONLINEAR ANALYSIS FOR PREDICTION USING SDOF MODEL OF HEAVY-WEIGHT FLOOR IMPACT SOUND LEVEL REDUCTION WITH THE CAR TIRE FOR DRY FLOATING FLOOR STRUCTURE IN THE LABORATORY

In this paper, we investigated predicting the reduction of heavy-weight floor impact sound level that takes into account nonlinearity due to tire impact. In analysis, we compared the mass calculation methods of five models that focused on the impact frequency of the impact source. We showed that it is effective to calculate the area of a circle whose radius is equivalent to the maximum amplitude of the wavelength of the bending wave at the impact frequency. In the 63 and 125Hz, more than 90% of the differences between predicted and measured values were within ±5dB.