ADAPTATION OF OFFICE BUILDING SPACE FOR EXPERIMENTAL DETERMINATION OF SOUND TRANSMISSION THROUGH A SERVICE SHAFT

Abstract

This research investigates acoustic energy propagation via flanking paths associated with building service installation shafts, utilizing a dedicated in-situ experimental test facility established across two adjacent office volumes. Five sequential structural modifications (Variants 0-D) were evaluated using airborne sound insulation and vibrometric analysis to quantify secondary transmission. Initial structural decoupling (Variant A) achieved DnT,w with an improvement from 25 to 56 dB. However, subsequent measurements confirmed a persistent flanking transmission path, with acoustic energy being radiated into the receiving room through the external façade system. The final configuration (Variant D) provided shaft/wall ΔLP in range to 1 to 6 dB in specific frequency regions. It has been shown that the method based on ISO 16283-1 is not suitable in this case because sound transmission through individual structures does not have a sufficient signal ratio. Future work will therefore transition to the in-situ intensity method (ISO 15186-2) for precise characterization of different sound energy transfer paths.