In situ evaluation of the vibration reduction index Kij

2008 ◽  
Vol 123 (5) ◽  
pp. 3615-3615
Author(s):  
Arianna Astolfi ◽  
Alessandro Schiavi ◽  
Cristiana Taricco ◽  
Simone Geroso ◽  
Fabrizio Bronuzzi ◽  
...  
Keyword(s):  
Vibration Reduction ◽  
Reduction Index

Flanking transmission of airborne sound involving wooden and stone elements in historical buildings

2018 ◽  
Vol 25 (4) ◽  
pp. 363-376 ◽  
Author(s):  
Rui Calejo Rodrigues ◽  
Dóris Queirós ◽  
Elsa Caetano
Keyword(s):  
Theoretical Prediction ◽  
Standard Procedure ◽  
Vibration Reduction ◽  
Stone Masonry ◽  
Prediction Methods ◽  
Masonry Walls ◽  
Acoustic Behaviour ◽  
Airborne Sound ◽  
Reduction Index

Historical old buildings bring together a whole set of unique characteristics with substantial influence on the acoustic behaviour, especially concerning the junctions between light and heavy elements, as is the case with wooden floors and stone masonry walls. The lack of information about the acoustic characteristics of wooden structures leads to the use of theoretical prediction methods, which do not accurately represent real conditions. The wooden floor’s complex design hampers the study of its acoustical behaviour. This difficulty becomes greater when the analysis targets the structural systems instead of the single elements. Consequently, the need of a deeper knowledge about the characteristics which influence the acoustic behaviour of these junctions leads to the research on the acoustic component associated with the flanking transmission paths of airborne sound – vibration reduction index ( Kij). Structural reverberation times ( Ts) for both elements were acquired in order to feature the in situ real condition. ISO 10848-1 standard procedure was followed for both measurements. In situ flanking transmission measurements between wooden structural floors and stone masonry walls will allow their comparison with theoretical prediction methods, as defined by the EN 12354-1 standard method. Results show a great deviation between in situ measurements of the vibration reduction index ( Kij) and the obtained results for the same index through theoretical models.

The Vibration Reduction Index Kij: Laboratory Measurements for Rigid Junctions and for Junctions with Flexible Interlayers

2006 ◽  
Vol 13 (2) ◽  
pp. 99-111 ◽  
Author(s):  
Charlotte Crispin ◽  
Bart Ingelaere ◽  
Manuel Van Damme ◽  
Debby Wuyts
Keyword(s):  
Vibration Reduction ◽  
Laboratory Measurements ◽  
Reduction Index

Vibration Reduction Index of a T-Junction With a Flexible Interlayer

2012 ◽  
Vol 134 (2) ◽  
Author(s):  
J. Alba ◽  
E. Escuder ◽  
J. Ramis ◽  
R. Del Rey ◽  
E.G. Segovia
Keyword(s):  
Near Field ◽  
Vibration Reduction ◽  
Scale Model ◽  
Reliable Prediction ◽  
The Cost ◽  
Elastic Layers ◽  
Sound Reduction ◽  
Predictive Formulas ◽  
Expression Of Uncertainty ◽  
Reduction Index

This paper describes the procedure followed to evaluate the vibration reduction index for T-junctions with inserted flexible elements and proposes new equations to complement the standard EN 12354-1:2000. The experiment described in this work is based on a 1:3 scale model of a T-junction with a flexible interlayer. It was used to obtain a significant reduction in the cost of the configurations under study. We chose to carry out vibration measurements by near-field acoustic holography (NAH) in order to avoid the risk of accelerometer interference. Flanking transmission was determined for different elastic layers with the objective of quantifying the effect of the flexible interlayer and to compare the results obtained with predictive formulas. The results enabled us to propose new equations to complement EN 12354-1:2000 for the reliable prediction of the apparent sound reduction index. The uncertainty associated with the different average velocity levels is determined according to the Guide for the Expression of Uncertainty of Measurement (GUM).

Vibration Reduction Analysis of an Old Residential District under Vehicle Load

2014 ◽  
Vol 522-524 ◽  
pp. 1697-1702
Author(s):  
Bo Huang ◽  
Tang Dai Xia ◽  
Peng Fei He
Keyword(s):  
Finite Element Method ◽  
Finite Element ◽  
Vibration Reduction ◽  
Seismic Load ◽  
Far Field ◽  
Vehicle Load ◽  
Residential District ◽  
Bored Piles ◽  
Reduction Effect

Vibration phenomena on buildings in old residential district under non-seismic load are increasing. Given the vibration phenomenon on buildings in an typical old residential district under vehicle load, cast-in-situ bored piles in rows are suggested to reduce the vibration through analysis. Finite element method (FEM) is used to simulate vibration reduction effect of piles with different lengths. Considering analysis of the isolation of Rayleigh wave from far field and the result of FEM, 40 meter is the reasonable length of the vibration reduction piles. A vibration reduction solution is presented.

Analysis of Predictive Calculation Methods of Airborne Sound Insulation

2016 ◽  
Vol 835 ◽  
pp. 573-578 ◽  
Author(s):  
Naďa Zdražilová ◽  
Denisa Donová ◽  
Iveta Skotnicova
Keyword(s):  
Acoustic Properties ◽  
Sound Insulation ◽  
Building Structures ◽  
Calculation Methods ◽  
Airborne Sound ◽  
Mutual Comparison ◽  
Sound Reduction ◽  
Reduction Index

Acoustic properties of building structures are currently very actual theme with regard to the development of new building and insulating materials, while the methods for estimating the airborne sound reduction index evolve mainly from the second half of the 20th century. For mutual comparison of selected prediction methods and for determination of their suitability it has been provided a calculation of weighted sound reduction index RW [dB] from the input parameters of materials identified by laboratory measurements, calculation of weighted apparent sound reduction index R ́W [dB] and these values were compared with in-situ measurements. The aim of this paper is to determine the most appropriate method to calculate RW [dB] and R ́W [dB] values of lightweight building constructions with regard to their practical applicability, accuracy of estimation and complexity of the calculations.

scholarly journals AIRBORNE SOUND INSULATION IMPROVEMENT ON MASONRY PARTITIONS USING ADDITIONAL PLASTERBOARD LAYERS

2011 ◽  
Vol 3 (1) ◽  
pp. 33-40 ◽  
Author(s):  
Marius Mickaitis ◽  
Aleksandras Jagniatinskis ◽  
Boris Fiks
Keyword(s):  
Theoretical Calculations ◽  
Low Frequency ◽  
Masonry Wall ◽  
In Situ Measurements ◽  
Sound Insulation ◽  
Frequency Range ◽  
Airborne Sound ◽  
Sound Reduction ◽  
Reduction Index

For the purposes of accumulating knowledge of how to comply with requirements for new buildings of obligatory sound class C or enhanced acoustic comfort sound classes A and B (Lithuanian Building Technical regulations STR 2.01.07:2003), the article discusses improvement on airborne sound insulation of partitions between dwellings using additional plasterboard layers. The results of an empirical approach were obtained performing in situ measurements of the partitions of masonry from silicate blocks and expanded-clay concrete blocks. Theoretical calculations without the evaluation of flanking paths are added. The paper looks at the peculiarities of in situ measurement methods and the estimation of the limiting uncertainty of the sound reduction index. It is showed that the values of the in situ measurements of the airborne sound reduction index in accordance with requirements EN ISO 140 and EN ISO 717 series for rooms having volume higher than 50 m3 varies depending on frequency range. It has been stated, that improvement on the weighed airborne sound reduction index in the frequency range from 100 Hz to 3150 Hz depends on the properties of additional layers and on the characteristics of the main constructions. Resonance in the low frequency range arising due to additional layers may reduce the weighed airborne sound reduction index defined in the frequency range from 50 Hz to 3150 Hz. This fact must be taken into account when designing improvement on masonry wall insulation using an additional layer in dwellings.

scholarly journals Numerical Evaluation of the Vibration Reduction Index for Structural Joints

2012 ◽  
Vol 37 (2) ◽  
Author(s):  
Jaime Ramis ◽  
Enrique Segovia ◽  
Jesús Alba ◽  
Jesús Carbajo ◽  
Luís Godinho
Keyword(s):  
Numerical Evaluation ◽  
Vibration Reduction ◽  
Structural Joints ◽  
Reduction Index
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