Full scale model investigation on the acoustical protection of a balcony-like façade device (L).
The acoustical insertion losses produced by a balcony-like structure in front of a window are examined experimentally. The results suggest that the balcony ceiling is the most appropriate location for the installation of artificial sound absorption for the purpose of improving the broadband insertion loss, while the side walls are found to be the second best. Results also indicate that the acoustic modes of the balcony opening and the balcony cavity resonance in a direction normal to the window could have a great impact on the one-third octave band insertion losses. The maximum broadband road traffic noise insertion loss achieved is about 7 dB.
Prediction of the sound field into high-rise building facades due to its balcony ceiling form
This study presents the acoustic performance off tall building facades closed to roadway due to one of balcony configurations, namely ceiling, with an inclined form in terms of traffic noise reduction. Three inclined angles are tested (5,10, and 15°) with different balcony depths by using a Pyramid Tracing model developed by A. Farina. The results in terms of A-weighted sound pressure level reduction are expressed in free field into the balcony back wall. The protection level, defined as the difference in noise levels before and after inserting the proposed balcony form, has been used to assess the reduction offered by that configuration. A maximum reduction due to using these forms is obtained at higher floors and at balcony of 2 m depths and more. As a consequence of simulation results, it is found that the prediction of protection levels from 10th to 15th floor can be calculated from an empirical equation.
The acoustic performance of building façades in hot climates: Part 1—Courtyards
Abstract The acoustic performance of perforated screens of unusual geometry was investigated by means of model work and computer simulation resulting from diffraction theory in which the barrier produces an amplitude gradient (thnadner) or a phase gradient (splitter). The results indicate that the protection obtained is similar to that of a solid thin barrier of equal height for a wide range of frequencies when the receiver is near the barrier. The thnadner and splitter screens were then examined, by means of one-tenth scale models, as a part of a courtyard. The results show that a considerable reduction in traffic noise is achieved which is again of the same order as that of a courtyard with a solid wall.