建物構造体中における固体音の伝搬性状

抄録

The propagation characteristics of solid-borne sound in building structures are studied by field measurements on three standing buildings and scale model experiments using a simplified building structure. Both in the field measurements and the scale model experiments, vibration acceleration levels(V. A. L. )at a number of widely distributed points in the structures are measured as one point of the structure is excited. From the results of the scale model experiments, it is revealed that the relative V. A. L. at any point is determined by its distance(r)from the excitation point via the shortest route in the structure, regardless of the propagating direction. It is assumed that the variation of V. A. L. (L_r)in buildings can be expressed as, L_r=P_0-Nlog r-Mr(P_0 depends on the strength of excitation)and the value N and M are examined from the results of measurements. From the results of the scale model experiments, the value of N is determined to be 20, regardless of frequency. Using this value, the M value in each octave band is determined from the results of the measurements taken on the standing buildings. The result shows that the M value is approximately proportional to the square root of the frequency.