Acoustical proprieties of light brick walls and its effects on flanking transmission

Abstract

Light brick walls 8-10 cm thick are typical structures frequently used in Italian building constructions as a internal partitions between dwellings and as internal layer of double façade walls. Due to low surface mass and rigid connection to other horizontal and vertical structures, light brick walls are often responsible of high flanking transmission. The simplest acoustic modeling of this structure for the evaluation of sound transmission in buildings, is the approach proposed by the EN 12354 standards, where the brick wall can be considered as a homogeneous structure and main acoustic parameters required are the sound reduction index and the vibration reduction index Kij. The aim of this paper is to analyse results of physical and acoustical properties (sound reduction index, structural reverberation time, radiation efficiency) of a typical 8 cm thick brick wall measured in laboratory testing facility, used as a partition in different test configuration: single layer wall, double brick layer wall with internal thermal layer and as a component of lateral wall, where the Kij index flanking transmission were also evaluated. Experimental results are then compared with theoretical values in order to analyse difference with homogeneous structures.