Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The research presents the sound insulation in masonry walls coated with plaster. Three walls were built in laboratory, studied in specific tests. Measurements were carried out varying some components of the wall, such as the type of the block and the combinations of coarse mortar, plaster and stucco on the faces of the wall. The mortars used in the tests were industrialized and had an additive in their conglomerate that aimed to its structural and commercial improvement. Also, paints and textures were used alternately in the tests to verify the importance of this kind of coating on the sound transmission loss of the wall. The laboratory findings showed up the location of the coincidence frequency and the acoustic accomplishment of the coated masonry walls. Variation of these factors had a direct influence at the system hardness. The increase of the variation in the set caused by the addition of the mortar layers does vary, further of frequency of coincidence, the frequency of resonance wall thickness. It was still checked that three days of drying of the mortar was sufficient to have satisfactory results on the essays. The laboratory tests brought more agility with the evidence and the validation that the cure of the aggregate in the wall needs three days. Another important verification was the increase of 5 dB on the Weighted Noise Reduction Index (Rw) when the wall is coated in both faces. The using of paint and texture didn t contribute to the acoustic performance of the wall. Just, the utilization of texture shown a raise of acoustic performance of 1 dB on the Weighted Noise Reduction Index (Rw). That didn t happend with the duplication of the layer of plaster, that obtained acoustic insulation indicators lower than 1dB in the set. / A pesquisa investigou a maneira como acontece a isolação sonora em paredes de alvenaria estrutural com revestimento de argamassa. Foram construídas em laboratório três paredes, estudadas em ensaios específicos. O tipo do bloco e as combinações de chapisco, emboço e reboco foram avaliados alternadamente em cada bateria de ensaios. As argamassas utilizadas nos ensaios eram industrializadas e possuíam aditivos em seu conglomerado que visavam a sua melhora estrutural e comercial. Também, foram utilizadas tintas e texturas alternadamente nos ensaios para verificar a influência deste tipo de acabamento na perda de transmissão sonora da parede. As constatações laboratoriais mostraram a localização da frequência de coincidência e o desempenho acústico das paredes de alvenaria estrutural revestidas. A variação desses fatores possui influência direta conforme a rigidez do sistema. O seu aumento no conjunto causado pelo acréscimo de camadas de argamassa faz variar, além da frequência de coincidência, também a frequência de ressonância de espessura da parede. Aferiu-se, ainda, a possibilidade de diminuição dos dias de secagem da argamassa entre os ensaios realizados. Os testes em laboratório ganharam em agilidade, com a comprovação e validação do tempo de 3 dias para a cura da massa usada na parede. Outra importante verificação foi o incremento de 5 dB no Índice de Redução Sonora Ponderado (Rw) quando há o revestimento da parede em ambas as faces. A utilização de tinta e de textura não acrescentou ganhos acústicos substanciais para o conjunto da parede. Apenas, a utilização da textura apresentou um aumento de performance na ordem de 1 dB no índice de redução sonora ponderado (Rw). O que não aconteceu com a duplicação da camada de reboco, que obteve indicadores de isolação sonora inferiores a 1 dB no conjunto.

Orientador: Stelamaris Rolla Bertoli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T17:45:45Z (GMT). No. of bitstreams: 1 Ogasawara_AnaPaula_M.pdf: 4867597 bytes, checksum: 2e41fa9a8758569e674353f9afc74e71 (MD5) Previous issue date: 2006 / Resumo: A acústica arquitetônica é uma das áreas do conforto ambiental e, como tal, de grande importância para a qualidade do espaço, no que diz respeito ao grau de satisfação do usuário. Dentre as diferentes tipologias de edificações, os teatros primam por qualidade acústica, pois destinam-se essencialmente à transmissão de mensagens sonoras faladas, cantadas ou musicadas. Paradoxalmente, a literatura temática disponível no Brasil é praticamente inexistente, sendo enorme a dificuldade dos que se dedicam ao estudo da acústica arquitetônica, em obter informações sobre o objeto de estudo de sua disciplina. O objetivo desta pesquisa é avaliar o conforto acústico de oito salas destinadas a apresentações teatrais da cidade de Campinas através de elementos do projeto arquitetônico e de parâmetros acústicos que influenciam com a qualidade desses espaços para situações de palavra falada. Com esta finalidade, utilizou-se a técnica impulsiva para a análise acústica destas salas. A avaliação acústica vem das análises dos dados de nível de pressão sonora (NPS) em dB(A), dos espectros sonoros, tempo de reverberação (TR), clareza (C50), definição (D80), tempo central (Ts), tempo de decaimento inicial (EDT ¿ ¿Early Decay Time¿) e índice de transmissão da fala (STI ¿ ¿Speech Transmission Index¿). Os dados dos espectros possibilitam as predições do nível de interferência na fala (SIL) e também a classificação dos ambientes segundo as curvas de NC (Noise Criterion Curves). Os resultados foram avaliados através dos dados tabulados das avaliações, obtidos através da técnica impulsiva e dos elementos arquitetônicos de cada sala. Como resultado, constatou-se que todas as salas avaliadas garantem uma transmissão sonora eficiente principalmente nas médias e altas freqüências, sendo a principal fonte de ruído, as fontes interiores às edificações. A forma de apresentação dos resultados de cada teatro representa um método base para o procedimento de analise acústica. O cruzamento das informações da análise acústica com as características construtivas colabora para mostrar a importância do projeto arquitetônico estar interligado ao projeto acústico / Abstract: The architectural acoustics is an issue related to environmental comfort and, as such, of great importance for the quality of the space, concerning the satisfaction level of its user. Among the wide range of edification typologies, the theaters excel for their acoustic quality, since they are destined essentially for the transmission of spoken sound messages or songs. Paradoxically, the available thematic literature in Brazil is practically inexistent, which has become an enormous hindrance to those who have dedicated themselves to the study of the architectural acoustics, in obtaining information on its discipline. The main purpose of this project is to evaluate the acoustic comfort of eight rooms directed to theatrical presentations in Campinas city through elements of architectural project and of acoustic parameters which influence the quality of those spaces for speech situations. For this purpose, the impulsive technique was used for the acoustic analysis of these rooms. The acoustic evaluation comes from the analyses of the data of sound pressure level (SPL) in dB(A), sound spectrum, reverberation time (RT), clarity (C50), definition (D80), central time (Ts), early decay time (EDT) and speech transmission index (STI). The spectrum results make possible the predictions on speech interference level (SIL) and also the classification of the rooms according to noise criterion curves (NC). The results were appraised through the tabulated data of the evaluations, obtained through the impulsive technique and of the architectural elements of each room. As result, was concluded that all appraised rooms could guarantee an efficient sound transmission mainly in the medium and high frequencies, being the main noise source, the interior sources to the edifications. The form of presentation which results of each theater represents a method base for the acoustic analysis procedure. The crossing between the acoustic analysis information and the constructive features collaborates to demonstrate the importance of linkage between both architectural and acoustic projects / Mestrado / Arquitetura e Construção / Mestre em Engenharia Civil

Orientador: Stelamaris Rolla Bertoli / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-14T23:48:06Z (GMT). No. of bitstreams: 1 Neto_MariadeFatimaFerreira_D.pdf: 2194109 bytes, checksum: 43db0d9e68378992559f3db31ef023b9 (MD5) Previous issue date: 2009 / Resumo: O desempenho de uma edificação envolve aspectos fundamentais, como conforto, segurança e durabilidade. Dentro desses aspectos, podem ser avaliados os confortos acústico e térmico, segurança contra incêndio e, resistência estrutural, aos agentes agressivos e à água. Muitas vezes é somente após a entrega do edifício que, ao item conforto, passa a ser dada maior atenção, principalmente, pelo usuário que sente que o conforto acústico recebeu pouca importância durante o projeto e execução da obra. A questão do conforto acústico em edificações pode não estar ligada somente ao valor do isolamento da partição entre ambientes. A percepção total, parcial ou nula da conversação da vizinhança adjacente proporciona níveis de conforto que vão do indesejável ao ideal. Essa percepção da palavra falada pode ser um indicativo do nível de conforto que o usuário anseia. Para avaliar o desempenho de paredes entre unidades habitacionais e o conforto proporcionado foram avaliadas partições em edifícios residenciais no Brasil e em Portugal. No Brasil, as paredes avaliadas eram compostas por blocos cerâmicos de vedação, com espessuras que variam de 115 mm a 140 mm, blocos de concreto de vedação, com espessuras que variam entre 90 a 140 mm e bloco estrutural de concreto, com espessura de 190 mm. Em Portugal foram avaliadas paredes simples e duplas compostas por tijolos cerâmicos com espessuras de 110 e 150 mm. A avaliação foi dividida em parte objetiva, onde é medido o desempenho em relação ao isolamento ao ruído aéreo em laboratório e em campo, a inteligibilidade da fala, além da audibilidade e, parte subjetiva, onde um júri responde sobre a percepção de sentenças faladas, de um ambiente para outro. Os valores obtidos das medições do desempenho em paredes foram comparados com critérios referentes a cada país de origem e também comparados com critérios dos demais países, a fim de verificar o quanto os critérios brasileiros e portugueses aproximam-se dos demais critérios. Dos valores de desempenho em campo, das paredes, e de parâmetros utilizados na avaliação da inteligibilidade da fala, obtém-se, como proposta, valores de nível de conforto para cada ambiente proporcionado pelas paredes em avaliação. Dos resultados obtidos verifica-se que tanto o Brasil quanto Portugal ainda precisam melhorar o desempenho acústico das edificações residenciais porém, o Brasil, de um modo especial, deve melhorar ainda mais a qualidade acústica de suas edificações a fim de proporcionar aos usuários os níveis desejáveis de conforto e privacidade, oriundos do desempenho das partições e dos ambientes ocupados. / Abstract: The performance of a building involves fundamental aspects such as structural strength, durability, fire safety, impermeability and corrosion. Also fundamental are user related aspects such as acoustic and thermal comfort. These can be designed, measured and evaluated. However, it is often only after occupation of the building that the comfort item is given any attention by the user, who begins to feel that acoustic comfort received very little thought during the design and construction of the building. The issue of acoustic comfort may be not linked to just the value of the insulation of the partition between rooms. The perception, total, partial or inexistent, of conversation in an adjacent dwelling also contributes to comfort levels which may range from unpleasant to ideal. This perception of speech can be an indicator of the comfort level that the user considers desirable. In this thesis, the acoustic performance of walls between housing units was measured and the corresponding degree of comfort evaluated for some residential buildings in Brazil and Portugal. In Brazil, the walls measured were composed of infill ceramic bricks, with thicknesses ranging from 115 mm to 140 mm, infill concrete blocks, with thicknesses ranging from 90 to 140 mm and structural concrete blocks with a thickness of 190 mm. In Portugal single and double walls composed of bricks with thicknesses of 110 and 150 mm were measured. The evaluation was divided into two parts: objective, where the airborne sound insulation in both laboratory and field tests, speech intelligibility and audibility were measured; and subjective, where a jury responded to questions on the perception of sentences spoken in an adjacent environment. The values of wall performance were confronted with the criteria for each country and were also compared with the criteria of other countries, in order to ascertain how the Brazilian and the Portuguese criteria compare internationally. A new parameter for evaluation of acoustic comfort level in a room is proposed. This incorporates the field performance figures of sound insulation and parameters of speech intelligibility. The results indicate that both Brazil and Portugal still have to improve the acoustic performance of residential buildings. Brazil, especially, has a considerable way to go to improve the acoustic quality of its residential buildings in order to provide users with appropriate comfort and privacy levels. / Doutorado / Arquitetura e Construção / Doutor em Engenharia Civil

Orientador: Stelamaris Rolla Bertoli / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-25T11:37:51Z (GMT). No. of bitstreams: 1 Cunha_IaraBatista_M.pdf: 6288212 bytes, checksum: 6312c88b95bfe2f47d5d98532d33f1ce (MD5) Previous issue date: 2014 / Resumo: Nas práticas litúrgicas da Igreja Católica, fala e música compõem as principais atividades, portanto, a qualidade acústica nas igrejas é essencial. Atualmente, do ponto de vista acústico, a compreensão da palavra é a necessidade mais relevante dos ritos católicos. Os sistemas de reforço sonoro (SRS) são utilizados como auxílio na resolução de alguns problemas recorrentes nestes espaços que atingem a qualidade da compreensão da fala, como a dificuldade do alcance da voz humana a grandes distâncias ou a interferência de ruídos urbanos no ambiente interno. Esta pesquisa se propõe a investigar o uso destes sistemas e sua influência na resposta acústica das igrejas, com ênfase na inteligibilidade da palavra. Para isso, três igrejas católicas de diferentes volumes situadas na cidade de Campinas, SP foram avaliadas segundo os parâmetros acústicos Tempo de Reverberação (TR), Tempo de Decaimento Inicial (EDT) e Definição (D50), em bandas de oitava entre 125Hz e 4kHz, além do Índice de Transmissão da Fala (STI) e da Perda de Articulação de Consoantes (ALcons). As medições foram feitas pelo método de resposta impulsiva, em duas situações: com o sinal ligado no SRS e com o sinal ligado na fonte padrão omnidirecional. Desta forma, caracteriza-se cada ambiente nas condições "com" e "sem" o sistema de sonorização, permitindo a comparação de dados entre estas duas situações. Em todos os casos sem o uso do SRS, os edifícios apresentaram condições acústicas desfavoráveis para a compreensão da fala. O SRS mostrou diferenças favoráveis para inteligibilidade na maior parte dos resultados. No entanto, quando a resposta acústica do edifício não proporciona uma qualidade positiva, o SRS não foi suficiente para elevar a avaliação qualitativa da inteligibilidade para resultados ideais / Abstract: During Catholic services, speech and music are the main activities, thus, acoustical quality in the churches is essential. Currently, from the acoustic view, the understanding of words is the most important need of Catholic rites. The sound reinforcement systems (SRS) are used as a support in solving some recurring problems in these buildings, such as the difficulty for human voice to reach great distances or due to interference from urban noise in the indoor environment. This research intends to investigate the use of these systems and their influence on the acoustic response of the churches, with an emphasis on speech intelligibility. For this, three Catholic churches with different volumes, located in the city of Campinas, SP, were evaluated according to the acoustic parameters Reverberation Time (RT), Early Decay Time (EDT) and Definition (D50), in octave bands between 125 Hz and 4 kHz, and the Speech Transmission Index (STI) and Articulation Loss of Consonants (ALcons). Measurements were made by the impulse response method, through two different situations: with the test signal injected directly on the sound system and using the omnidirectional sound source. In all cases, without the use of SRS, the buildings showed unfavorable conditions for the acoustic speech understanding. The SRS revealed positive differences for intelligibility in most of the results. However, when the acoustic response of the building itself does not provide a good quality for speech understanding, the SRS was not sufficient to raise the quality of intelligibility for optimal results / Mestrado / Arquitetura, Tecnologia e Cidade / Mestra em Arquitetura, Tecnologia e Cidade

The prediction of the noise generated by en-route aircraft is gradually gaining in importance as the number of aircraft increases over the last few decades. While the studies of outdoor sound propagation have been focused on near ground propagation, the case when the sound source is high above the ground has not attracted much attention. At the same time there has been a lack of high-quality aircraft acoustic validation data sets that contain detailed acoustic, meteorology, and source-receiver position data. The DISCOVER-AQ data set, which was collected by Volpe in support of the Federal Aviation Administration (FAA), has greatly helped with studying the directivity and the Doppler effect in the comparison between simulation results and measurements. <div><br>To provide a more accurate prediction of en-route aircraft noise, we derived the analytic asymptotic solution of the sound field above a non-locally reacting ground due to a moving point source and a line source using the methods of the steepest descent and a Lorentz transform. The model predicts a much more accurate result for sound field above "soft" grounds, such as a snow-covered ground and sand-covered ground. At the same time, we derived a fast numerical algorithm based on Levin’s collocation for the prediction of the sound field in the presence of a temperature gradient, which can be applied to a wide range of acoustic problems involving integration. The achievements recorded in this thesis can be used to predict the sound field generated by aircraft, trains, and vehicles with a subsonic moving speed. In addition,<br>the model can be used for detection and design of moving sound source. <br></div>

<div><div><div><p>Tonal sounds are a particular problem of concern in building environments, arising from the widely used rotating machinery (e.g., compressors, fans, motors, trans- formers, etc.). In the recent trend of designing and manufacturing high-performance building mechanical systems, higher output power and higher rotation speed are pursued, this inevitably results in a more severe noise problem, since the equipment noise not only becomes louder but also shifts to a higher frequency region (which, in most cases, results in a poorer sound quality due to the shift in spectral balance and tonal components moving into the frequency regions where people are most sensitive to tones). Tonal sounds from rotary machines can be annoying, even at relative low levels.</p><p>Currently, noise criteria guidelines in Chapter 48 of the ASHRAE HVAC Applications Handbook can be used to design the building mechanical system, but this does not apply well for tonal noise. Reducing the limit for noise with perceptible tones is one common strategy in the industry. However, it’s not adequate for some cases, over-design in others. Thus, an adequate understanding of the annoyance threshold of tonal noises associated with building services equipment is valuable technical information not only in the design and manufacture of machines but also in the development of noise regulations related to building services equipment.</p><p>This research aims to develop a sound quality model that cooperates with sound level and tonalness and relates tonal building noises to the perceived annoyance.</p></div></div></div>

In room acoustics, the directional information of sound arrivals at a listening location can be used to diagnose the origins of problematic reflections so offending surfaces or other features can be properly treated. It can also be used for other purposes, including the study of psychoacoustic indicators. Many methods have been developed in the past to derive directional information, but despite their benefits, each has had significant drawbacks that have necessitated further research into their properties and development of an improved method. This thesis presents a review of past methods, their benefits and shortcomings. It discusses many theoretical and practical issues pertaining to the Polar ETC method and methods using the cross-correlation function. It also presents a new short-time correlation-based method (STCM) for gathering directional information of sound arrivals in rooms. Computer programs were developed for the implementation of the theory. Numerical simulations and experimental measurements are shown and the results are compared to those obtained by the Polar Energy Time Curve (ETC) method. The STCM is shown to be an improvement over past methods in terms of its ability to distinguish between simultaneous arrivals, its accuracy, its computational efficiency and its equipment requirements. Limitations of the method are also discussed.

No / A novel technique for the laboratory characterization of the frequency-dependent acoustic surface admittance of partly saturated samples of sands is presented. The technique is based on a standard laboratory de-watering apparatus coupled with a standard acoustic impedance tube. The dependence of the surface admittance on the degree of water saturation is investigated for two samples of sand with widely different flow resistivities. It is shown that a relatively small change (e.g., from 0% to 11% by volume) in the degree of water saturation can result in a much larger change (e.g., twofold) in the acoustic surface admittance. An empirical relationship is found between the peaks observed in the real part of admittance spectra for the low flow resistivity sand and the degree of water saturation. The data are compared with predictions of two widely used ground impedance models: a semiempirical single parameter model and a two parameter model. A modified two-parameter version of a single-parameter model is found to give comparable fit to the two-parameter model. However, neither model provides an accurate fit.

No / The Helmholtz integral equation formulation is used to produce the solution for the acoustic field reflected from a finite, thin, poroelastic plate in a rigid baffle with simply supported edges. The acoustic properties of the porous material are predicted using the effective fluid assumption. The solutions for the displacement of the plate and for the loading acoustic pressures are given in the form of the sine transform. The sine transform coefficients are obtained from the solution of a system of linear equations resulting from three integral Helmholtz formulations which relate the displacement of the plate and the acoustic pressures on the front and on the back of the plate. The effect of an air gap behind the plate in the front of a rigid wall is also considered. A parametric study is performed to predict the effect of variations in the parameters of the poroelastic plate. It is shown that thin, light, poroelastic plates can provide high values of the acoustic absorption even for low frequency sound. This effect can be exploited to design compact noise control systems with improved acoustic performance.

A modern control theory formulation of Active Structural Acoustic Control (ASAC) of simple structures radiating acoustic energy into light or heavy fluid mediums is discussed in this dissertation. ASAC of a baffled, simply-supported plate subject to mechanical disturbances is investigated. For the case of light fluid loading, a finite element modelling approach is used to extend previous ASAC design methods. Vibration and acoustic controllers are designed for the plate. Comparison of the controller performance shows distinct advantages of the ASAC method for minimizing radiated acoustic power. A novel approach to the modelling of the heavy fluid-loaded plate is developed here. Augmenting structural and acoustic dynamics using state vector formalism allows the design of both vibration and ASAC controllers for the fluid-loaded plate. This modern control approach to active structural acoustic control is unique in its ability to suppress both persistent and transient disturbances on a plate in a heavy fluid. Numerical simulations of the open-loop and closed-loop plate response are provided to support the theoretical developments. / Ph. D.