Perceived Loudness of Sound Transmitted through Light Weight and Heavy Weight Walls

2013 ◽  
Vol 649 ◽  
pp. 101-104 ◽  
Author(s):  
Monika Rychtáriková ◽  
Bert Roozen ◽  
Herbert Müllner ◽  
Mathias Stani ◽  
Vojtech Chmelík ◽  
...  

When assessing the sound insulation quality of buildings constructions, policy makers and investors typically demand for single number ratings and sound insulation classes that allow for easy ranking of building products. Converting the full frequency content of a precisely measured or calculated structure into a single number, which takes into account all aspects of the insulation performance in a balanced way, is a challenging task. The recently proposed draft standard 717 proposes to take into account also frequencies below 100 Hz. This makes the single value rating even more complicated, since the transmission spectra R (dB) of walls can be qualitatively very different above and below 100 Hz, and even more, since, particularly at low frequencies, human hearing depends not only on frequency but also on the absolute sound level. This article presents a comparison between masonry and light-weight walls with different R value, in terms of the perception of loudness of typical living room, traffic noise and machinery noise transmitted through the walls. The effect of temporal and spectral features of the presented stimuli on loudness perception is analyzed.

2013 ◽  
Vol 38 (1) ◽  
pp. 115-124 ◽  
Author(s):  
Naveen Garg ◽  
Anil Kumar ◽  
Sagar Maji

Abstract The paper presents an extensive review investigating the practical aspects related to the use of single- number ratings used in describing the sound insulation performance of partition wall panels and practical complications encountered in precise measurements in extensive frequency range from 50 Hz to 5 kHz. SWOT analysis of various single number ratings is described. A laboratory investigation on a double wall partition panel combination revealed the significant dependence of STC rating on transmission loss at 125 Hz attributed to 8 dB rule. An investigation conducted on devising alternative spectrums of aircraft noise, traffic noise, vehicular horn noise and elevated metro train noise as an extension to ISO 717-1 Ctr for ascertaining the sound insulation properties of materials exclusively towards these noise sources revealed that the single-number rating Rw + Ctr calculated using ISO 717-1 Ctr gives the minimum sound insulation, when compared with Rw + Cx calculated using the alternative spectrums of aircraft noise, traffic noise, etc., which means that material provides a higher sound insulation to the other noise sources. It is also observed that spectrum adaptation term Cx calculated using the spectrum of noise sources having high sound pressure levels in lower frequencies decreases as compared to ISO 717-1 Ctr owing to significant dependence of Ctr at lower frequencies.


2019 ◽  
Vol 105 (5) ◽  
pp. 727-731
Author(s):  
Inho Kim ◽  
Jongkwan Ryu ◽  
Sungchan Lee

In this study, the influence of a perforated ceiling on the floor impact sound was investigated. The floor impact sound measurements were conducted both with and without suspended ceiling including the perforated and nonperforated panel, using heavy and light weight impact sources in a reinforced concrete test building. The results indicated that the perforated ceiling with and without absorption sheet greatly reduced the resonance of floor impact sound by the non-perforated ceiling. However, the perforated ceiling without an absorption sheet did not improve the single number quantity (SNQ, rubber ball: L′iA,Fmax,V.T and tapping machine: L′n,w) for the floor impact sound insulation. The perforated ceiling with attached absorption sheet produced SNQs of 2 dB lower and higher than that produced by the non-perforated ceiling for heavy and light weight impact sources, respectively. It was also found that the improvement in the floor impact sound insulation after the installation of the perforated ceiling was related to the mass-spring-mass system, rather than the absorption area of the receiving room.


Acta Acustica ◽  
2022 ◽  
Vol 6 ◽  
pp. 3
Author(s):  
Catherine Lavandier ◽  
Mehdi Regragui ◽  
Romain Dedieu ◽  
Carine Royer ◽  
Arnaud Can

The influence of fluctuating road traffic noise on perceived disturbance during a reading task as well as on performance, inside a living room with closed windows, is presented in this paper. Sixteen 2-min sound sequences were created combining two variables: the number of events (four levels varying from one to four car pass-bys) and the peak emergence above the background noise (four levels with a 5 dB(A) step) keeping limited variations of LAmax, 1s. The noise impact was evaluated through a reading task of texts synchronized with the sound sequences, for participants classified into fast or slow readers, and sensitive or non-sensitive to noise. The comprehension rate of the texts decreases as the background sound level increases. The reading speed decreases during the rising front of a peak, and goes back to its former regular reading speed during the descending front of the peak. This slowdown during the rising front reaches 14% for slow readers. The declared disturbance is higher for slow readers compared to fast readers, and higher for noise sensitive persons compared to non-sensitive persons. The influence of the acoustic indicators on the reading disturbance is very small compared to the influence of personal factors. There is even no influence of the number of events on this disturbance.


2016 ◽  
Vol 24 (1) ◽  
pp. 35-52 ◽  
Author(s):  
Anders Homb ◽  
Catherine Guigou-Carter ◽  
Andreas Rabold

Wooden building systems, including cross-laminated timber elements, are becoming more common. The last few years have seen new developments and documentation of innovative types of cross-laminated timber floor assemblies. Regarding impact sound associated to walking persons, running or jumping children, such floor assemblies can be regarded as a weak part. So far, there are no reliable standardized calculation models available, for prediction of impact sound in the entire frequency range. Therefore the design is always based upon previous experiences and available measurements. This article presents the results of a number of well controlled sound insulation measurements of cross-laminated timber/massive wood floor constructions conducted in laboratories. The collection of data and results analysis highlight some basic phenomena. For instance, how structural differences related to the grouping of the constructions change the frequency distribution of the impact sound level and the single number quantities. Another significant result is the influence of the dynamic stiffness of the resilient interlayer of floating floor systems and the mass per unit area of the floors. Based on this analysis, the aim is to identify similarities and carry out simplifications. The data will be further processed and used in the development of prediction models and optimization process of cross-laminated timber floor assemblies.


Author(s):  
Jan Felcyn

Abstract Purpose Road traffic noise is the most common source of noise in modern cities. The noise indicators used to manage noise do not take into account its temporal structure. However, in cities the traffic flow varies during the day, peaking due to congestion and more fluent periods. In this research we sought to analyze how people (giving answers on a numerical ICBEN scale) perceive noise stimuli with the same LAeqT values but different time structures (more/less noise events, different amplitude envelopes). Methods 31 people with normal hearing took part in an experiment conducted in an anechoic chamber. Participants listened to 18 different noise recordings and rated each of them using the numerical ICBEN scale regarding noise annoyance. Results The results showed that only sound level was a statistically significant factor. However, based on people’s remarks about noise, we can also say that the more intermittent the noise is, the more negative feelings it evokes in people. Conclusions Time structure does not have a significant influence on people’s judgments about noise annoyance. However, people tend to have a preference for a steady noise rather than an intermittent one.


2021 ◽  
Vol 263 (3) ◽  
pp. 3064-3072
Author(s):  
Takashi Yamauchi ◽  
Atsuo Hiramitsu ◽  
Susumu Hirakawa

The air layer between the interior finishes and the structure is used as piping and wiring space. In many cases, ceilings and dry-type double floors are commonly constructed in Japan. However, the effect of the air layer of ceilings and dry-type double floors on the heavy-weight floor impact sound insulation performance has not yet quantitatively investigated. Therefore, in this study, the same floor and ceiling structures were constructed for concrete and CLT buildings, and the heavy-weight floor impact sound was investigated. As results, it was confirmed that the reduction amount of the heavy-weight floor impact sound by the ceiling tended to be smaller in CLT buildings than in concrete buildings. However, the trends were similar. Due to the dry-type double floor structure, the heavy-weight floor impact sound level was increased in concrete building and decreased in CLT building at 63 Hz in the octave band center frequency band. Therefore, it can be said that the dry-type double floor structure can be used to improve the heavy-weight floor impact sound performance in the CLT building.


1972 ◽  
Vol 52 (1A) ◽  
pp. 119-119
Author(s):  
K. A. Mulholland ◽  
R. H. Lyon

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