Energy flow in timber structures at low, mid and high frequencies

Within the context of efficient and sustainable design of buildings, a trend towards lightweight structures, e.g. timber structures, is recognizable. This trend implies the necessity to be able to predict serviceability and comfort as well as sound transmission in order to fulfill building requirements. To generate reliable prediction methods, the transfer of energy between building components has to be investigated. In the low frequency range, the Finite Element Method (FEM) is a convenient tool to predict the vibroacoustic behavior. The applicability of the FEM is limited due to the sensitivity of the results at higher frequencies. Thereby, the increased number of modes enables the use of statistical methods like the Statistical Energy Analysis (SEA) to cope with the uncertainty. The SEA delivers robust results in the mid-frequency range for a sufficient number of modes per band. However, the SEA is limited with respect to the resolution in space and frequency. At high frequencies, the SEA is not able to represent through-thickness effects of plate-like structures. As both techniques have a restricted validity regarding the frequency range, averaging techniques of the SEA procedure are applied in the postprocessing of the FEM to obtain an adapted hybrid approach. By varying the subsystem to be excited it is possible to determine Energy Influence Coefficients (EIC), which describe the normalized energy level of the individual subsystem with respect to the input power. If the SEA requirements are fulfilled the Coupling Loss Factors can be determined by inverting the EIC-Matrix. There will be a comparison between various types of geometries as well as different types of junctions. E.g., the effect of an elastic layer shall be characterized. Furthermore, there will     «

Within the context of efficient and sustainable design of buildings, a trend towards lightweight structures, e.g. timber structures, is recognizable. This trend implies the necessity to be able to predict serviceability and comfort as well as sound transmission in order to fulfill building requirements. To generate reliable prediction methods, the transfer of energy between building components has to be investigated. In the low frequency range, the Finite Element Method (FEM) is a convenient t...     »