Conference_programme: 1: Absorbing materials
Lecture: Analysis of the results of the sound absorption coefficient for low frequencies of laminate bamboo resonant membrane panels
Author(s): Barbosa De Sá Brunno Guilherme, De Ulhôa Carvalho Maria Luiza, Gonçalves De Almeida Jaime
Summary:
This work is part of the analysis of master course results called "Room Acoustics and Glued Laminated Bamboo (BaLC): Panels tests for acoustic conditioning" which evaluated the using of BaLC, from the Dendrocalamus giganteus species, for the acoustic treatment of enclosures spaces. Were constructed 12 panels with 107cm x 107cm x 4mm thick in BalC, in order to set them in resonant membranes devices type to low frequencies absorption. These panels were acoustically tested with internal air cavities thick as 100mm, 75mm and 50mm and with the same cavities filled with glass wool. The calculation of the resonant frequency of each system was performed to estimate the frequency band in which the device had a maximum sound absorption. The tests of sound absorption coefficient followed the international standard ISO 354: 2007 with sample 12m² in a reverberation chamber for each thickness cavity with and without glass wool filling. The results showed the resonance frequency of 100Hz and thus the maximum sound absorption coefficient at the same frequency for all sampling configurations. In the analysis of sound absorption coefficients, were found a variation from 0,387s to empty cavity with a thickness of 50mm to 0,778s to 50mm cavity filled with glass wool, both at 100Hz. The study demonstrated a significant potential to use the BaLC for sound absorption, thus entering a non-conventional and renewable material in the room acoustics possibilities. It is suggested to improve the study, the tests using the variation in panel dimensions and their comparison with the theoretical prediction.
Corresponding author
Name: Prof Brunno Guilherme Barbosa de Sá
e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.
Country: Brazil
