Sound insulation properties of sandwich panels

Abstract

Abstract The sound transmission via building enclosures of finite dimensions has a resonant and inertial components. The resonant transmission of sound takes place in the mode of self-induced vibrations depending on the degree of self-coordination of its own wave field with sound fields present in the air on both sides of the enclosure. The most effective method of sound insulation enhancement of sandwich panels is to reduce the resonant transmission of sound by acoustic separation of the layers. This design solution provides the greatest reduction of the resonance frequency “mass – spring – mass”. Experimental studies for determining the intrinsic sound insulation of sample sandwich panels have been conducted in reverberation chambers in a diffuse sound field. The acoustic separation of sandwich panel layers allowed for the increase of the airborne noise insulation index up to 4 dB: from Rw = 38 dB to Rw = 42 dB (for samples with polystyrene foam cores). For the sample with mineral wool core, the increase of the airborne noise insulation index was 8 dB: from Rw = 39 dB to Rw = 47 dB. The results obtained allow us to develop rational constructive solutions for enclosures of civil and industrial buildings of sandwich panels, taking into account the spectrum of insulated noise. Improving the sound insulation of sandwich panels is provided without a significant increase of their mass and thickness.