ACA – New Research and Testing Competence for Timber Constructions with a focus on low frequencies in Austria
Invited paper
Holzforschung Austria
Monday 1 june, 2015, 11:40 - 12:00
Auditorium 2 (592)
Abstract:
Timber-frame and solid timber construction methods became standard construction modes for multi-storey buildings and terraced houses. To give consideration to the particular sound insulation issues of timber- and light-weight constructions a new research project in building acoustics has been launched in Austria in July 2014. The overall goal of ACA is to establish the required infrastructure and concentrate the required competence of three institutions (HFA, TGM, TU Vienna) with different approaches to building acoustics.
This cooperative project will lead to acoustic test facilities for lightweight constructions where the research topics “low frequencies” and “subjective perception” can be on focus in particular.
Therefore the installation of two test stands is planned, taking into account experience of different European acoustic test facilities and already carried out research like German and Austrian round robin tests and their documentation. Furthermore a literature review showed various publications to sound field distribution in test boxes, niche effect, damping coefficient etc. and, relevant standards, which are, apart from ongoing discussion on this topic, considered in the planning process too.
First we had to get an idea about the necessary dimensions of the test chambers to fulfill the requirements on the frame conditions for reproducible building acoustic measurements in the extended frequency range below 100Hz. A parametric study of the future source and receiving room is presented which was used to define the best combination of room dimensions. The indicators of diffusivity where calculated by a FEM Model. The Model was validated through a comparison of the calculated and measured sound pressure field in the source- and receiving room of the test facility at TGM during a STL measurement.
This paper shows, the comprehensive considerations which led to the design of 2 acoustic test facilities for lightweight building components and describes the first steps of the scientific approach.