Calibration of the ISO tapping machine for finite-element prediction tool on a wooden-base floor

Abstract

One important challenge of the wooden constructions is to achieve a high quality of acoustic insulation, especially decreasing the impact noise in the low-frequency range. In order to avoid over-designed solutions and expensive experimental tests in the design phase, reliable prediction tools are called for. This article is an initial investigation of modeling the ISO standardized tapping machine on a cross-laminated timber floor, using finite element method. The wooden-based floor was first calibrated in terms of its dynamic properties. The influence of the material properties of the cross-laminated timber floor was discussed. The force generated by the tapping machine was then introduced in the established cross-laminated timber model. The model was finally validated by comparing the simulation results with the measured accelerations.

An efficient analytical method to obtain the homogenised frequency-independent elastic material properties of cross-laminated timber elements

“…Therefore, there are a total of 21 independent elastic constants in Eqs. (7) and (8). Timber, a building block of CLT, can be considered a special case of anisotropic material, namely an orthotropic material.…”

“…In vibro-acoustics, CLT may be modelled on a layerwise basis with homogenised layers (laminae/plies) that do not consider the individual timber planks [5][6][7]. To simplify the solution of such models, CLT elements can be further homogenised to act as an Equivalent Single Layer (ESL).…”

Low-frequency impact sound of timber floors: A finite element–based study of conceptual designs

“…It should be noted, however, that, although not widely applied in the industry, there is an interesting body of research on building acoustics and impact sounds. 7,8…”

“…It should be noted, however, that, although not widely applied in the industry, there is an interesting body of research on building acoustics and impact sounds. 7,8 In the high-frequency regions of the traditional impact sound measurement range (100-3150 Hz), the modal density is high, and using FE models would be a more computationally demanding task. Computational tools were not available during the early development of multi-story concrete buildings.…”

“…Since simulations of tapping machine impacts can be challenging, 8 and as these simulations may not accurately represent a footfall in the low-frequency range, 9,10 simulations of transient impacts are avoided in this study. The insulation of airborne sound is a frequency response function (FRF), proportional to the difference of the sound power in a source room to the sound power in the receiving room as a function of frequency, and it is dimensionless because it is expressed in decibels.…”