Vibroacoustic investigation of light-weight ceilings - Modeling aspects and design guidelines

In order to set up guidelines for the design of light-weighted ceilings for timber constructions, investigations based on both measurements and numerical models have been carried out in the research project "`VibWood"' an TU München and HAW Rosenheim [5]. A semi-analytical approach for the prediction of radiated sound is presented, which is based on Integral Transform Methods. The method can be applied in the post-processing of a Finite-Element-computation. Thus as a first step the structure, consisting of a cross laminated timber ceiling with ffoating floor and suspended ceiling, is build-up in a Finite-Element-model, where the material properties of wood and the characteristics of the system are considered. The model is parameterized to enable computations with varying geometry and material parameters and calibrated with measurements using model-updating-techniques. The model for the air in the cavity of the suspended ceiling is discussed, where a FSI-model with acoustic fluid elements is compared against simplified engineering approaches.