Prediction of low-frequency structure-borne sound in concrete structures using the finite-difference time-domain method

Abstract

Due to limitations of computers, prediction of structure-borne sound remains difficult for large-scale problems. Herein a prediction method for low-frequency structure-borne sound transmissions on concrete structures using the finite-difference time-domain scheme is proposed. The target structure is modeled as a composition of multiple plate elements to reduce the dimensions of the simulated vibration field from three-dimensional discretization by solid elements to two-dimensional discretization. This scheme reduces both the calculation time and the amount of required memory. To validate the proposed method, the vibration characteristics using the numerical results of the proposed scheme are compared to those measured for a two-level concrete structure. Comparison of the measured and simulated results suggests that the proposed method can be used to simulate real-scale structures.

Relationship between sound radiation from sound-induced and force-excited vibration: Analysis using an infinite elastic plate model

“…The impact sound insulation of floors in collective housing units is also included in this issue. To predict the sound radiation from force-excited vibration of complex building structures, Asakura et al 7 solved the equations of motion for a plate theory using the finite-difference timedomain method. The governing equation used in the literature is based on the bending vibration of elastic plates driven by concentrated force excitation.…”

“…From the approximate solutions of the transmission coefficient for random-incidence sound,ŝ f ðxÞ, in Eq. (7) and the radiated sound power under point force excitation, PðxÞ, in Eq. (19), the following relation is derived: s f ðxÞ ¼ e ðxÞPðxÞ; (20) where the conversion function, e(x) is as follows:…”

Finite-difference time-domain simulation of floor-impact sound excited by one-dimensional contact model and its application to auralization of floor-impact sound

“…2(c) and the thickness of the slab is 200 mm; this setup is called Arrangement-2, which is used only for the validation of the numerical results by comparison with the results shown in [31]. The coupling scheme between the sound and vibration field is taken from [11]. Then, the excitation characteristics affected by the impact ball, bang machine, and the hammer installed in the tapping machine are predicted.…”

“…On the other hand, structure-borne sound transmission characteristics can also be numerically predicted by statistical energy analysis (SEA) [3][4][5], finite-element method (FEM) [6], and finite-difference time-domain (FDTD) method [7][8][9][10][11][12][13]. Particularly in the prediction by the FEM and FDTD methods, the floor-impact sound is predicted on the basis of discrete numerical schemes.…”

Prediction of Vibration-Mode-Induced Noise of Structure–Acoustic Coupled Systems

“…Several researchers have attempted to predict the floor impact noise using the impedance methods and finite element method (FEM) [19], finite difference time domain (FDTD) [20][21][22][23][24], and statistical energy analysis method (SEA) [25]; however, the accuracy of these methods is limited. In general, the impact generated in a source room is transmitted through a slab in the form of vibrations and converted to sound on the ceiling surface.…”