| Keywords |
Sound reduction index ; Sound insulation ; Single lightweight panel ; Specimen size ; Setup position |
| Abstract |
In KS F 2860, the area of test opening for measurement of airborne sound insulation in a laboratory should be approximately 10 m2 for specimen. However, measurement of sound reduction index (SRI) using 10 m2 specimen has many disadvantages such as specimen setup time. So, in the early stage of sound insulation design for building element, it would be useful to install the small-sized specimen. The purpose of this study is to evaluate the sound insulation of single lightweight panels by the specimen size which is considered to occur the first resonance frequency below 100 Hz. In the current study, sound insulation measurements were performed on 7 small-sized specimens in accordance with the variation of panel thickness and density, and SRI between small-sized and standard-size specimens was compared for 3 specimens. The result showed that the single-number quantities of small-sized panel were similar to that of 10.5 m2 standard-size panels within 2 dB. In the case of 7 single panels, the single-number quantities (Rw) showed in the range from 37 to 44 dB. SRI of the small-sized panels below critical frequency didn’t show the mass law because of the variation of boundary condition and radiation efficiency. |