Insertion loss of asymmetrical balconies on a building façade

Abstract

The acoustical insertion loss of asymmetrical balconies on high-rise buildings was studied experimentally using a 1:3 scaled down model in the present study. Four balcony forms featured by the presence of a full-height side-wall were included. A linear loudspeaker array was adopted as the sound source. The effects of source orientation and balcony elevation angle on the insertion loss and its spectral variation were examined. The position of the full-height side-wall relative to the sound source significantly affects the balcony insertion loss. It is observed that the maximum traffic noise amplification and attenuation are both ∼6 dBA. Results also suggest that the balustrade has no effect on the insertion loss spectral variation pattern, though the insertion loss magnitude could be much reduced without it in the presence of a short side-wall. This short side-wall determines the insertion loss spectral variation pattern. Significant sound amplification is found at frequencies of the odd order transverse modes, the longitudinal modes, and their coupled modes regardless of balcony form and elevation angle. It is also found that the major acoustic mode interactions are basically independent of source orientation for balconies without the short side-wall.

A critical review of acoustic modeling and research on building façade

“…Some researches opted to study the acoustic characteristics of a façade in laboratories. 37 –52 Díaz and Pedrero 37 and Díaz et al 38 experimentally investigated the effect of rolling shutters and shutter boxes on the sound insulation properties of a façade window. The study contained a summary of sound insulation from airborne noise in several types of windows with a built-in shutter and prefabricated box.…”

“…On the other hand, owing to the large dimensions of the façade structure, some researchers have chosen to use scaled configurations to facilitate the tests. Tang et al 40 experimentally studied the insertion loss of asymmetrical balconies on a building façade with a 1:3 scaled-down model. It was shown that the position of the sound source relative to the full-height sidewall significantly affects the balcony insertion loss.…”