表面仕上げ材による床衝撃音の低減効果

抄録

Measurements were made with test hammers of four different specifications-the combination of the Mass and the Radious-and of the Fall Height being changed at intervals within the range 1〜32cm. First the usual frequency characteristics of ⊿L were obtained by a 1/3-octave-band frequency analysis for a single impact with a multichannel analyzer operating in fast and peak-level-hold modes. Since the shape of ⊿L curves are, as is well-known, very simple and resemble to each other, it is enough to take f_0, the frequency where the curve rises up from the horizontal axis. our In addition, out results show a noticeable close relationship between f_0 and such level difference as L_O-L_A, measured with a test covering. Finally, it was found reasonable to illustrate the experimental results on a diagram of M・H・R^&lt-1/2&gt vs f_0・H^&lt-1/2&gt, that is, the properties of a sample are shown as a single curve indicating clearly the individual characteristics. For instance, the slope of the curve for carpet has a sudden change at a certain impact condition, and so-called needle-punch carpet is quite different from a usual elastic plate. A calculation diagram was introduced to estimate the impact noise reduction of floor coverings under optional conditions of free-drop hammers.