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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Análise numérica de lajes treliçadas pré-moldadas com adição de resíduo de borracha

Santos, Marcos Rebuá dos [UNESP] 13 April 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-04-13Bitstream added on 2014-06-13T20:53:07Z : No. of bitstreams: 1 santos_mr_me_ilha.pdf: 6170851 bytes, checksum: 7e371acd2e98e6056215eb6fcf122052 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho, resultados experimentais relacionados a flechas imediatas de protótipos de lajes pré-moldadas treliçadas biapoiadas, com concreto com e sem resíduo de borracha de pneu, são comparados com resultados numéricos obtidos com base nas recomendações da NBR 6118 (ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS - ABNT, 2003) e do CEB-90 (COMITÊ EURO-INTERNACIONAL DU BÉTON - CEB, 1993). Foram feitas as seguintes análises. Na primeira, aplicaram-se as recomendações dos códigos ao elemento estrutural como um todo visando avaliar a sua rigidez; em seguida, com a expressão procedente da resistência dos materiais, foi calculada a flecha imediata. Estas modelagens numéricas estão referenciadas no texto como Branson, que representa a modelagem adotada pela NBR 6118:2003, e CEB-90. Na segunda, com o auxílio do sistema computacional ANSYS®, as expressões para o cálculo da rigidez segundo os códigos foram aplicadas aos elementos finitos que compunham os protótipos e não mais aos protótipos como um todo. Levou-se em consideração o carregamento incremental e este tipo de análise não linear gerou os resultados referenciados no texto como Branson discretizado e CEB-90 discretizado. Em uma terceira análise, com o auxílio do ANSYS®, utilizando-se o modo de carregamento incremental, aplicou-se, para cada elemento finito, a expressão do momento de inércia relativa aos estádios I ou II, dependendo do máximo momento fletor atuante no elemento e do momento de fissuração do protótipo. Os resultados obtidos foram referenciados no texto como Ansys - Estádios I e II. Para as análises mencionadas, foram utilizados os momentos de fissuração calculados, bem como os momentos de fissuração observados experimentalmente. Também foi analisado o comportamento da linha neutra. Considerando-se o Estado Limite de Serviço, os métodos de Branson, do CEB-90, do CEB-90... / In this work, experimental results related the immediate displacements of bi-supported lattice joist precast slab prototypes, with and without tire rubber residue in the concrete, are compared with numerical results obtained by the expressions of Branson, which is used by the brazilian standard NBR 6118 (ABNT, 2003), and by the method of CEB-90 (1993). The following analyses were made. In the first analysis, the expressions of the codes were applied for the whole structural element, obtaining its stiffness; so, with the use of the expression from the strength of materials, the immediate displacement was determined, called in this work of Branson and CEB-90. In the second analysis, with the help of the computational system ANSYS ®, the expressions for the calculation of the stiffness according to the codes were applied to the finite elements that were composing the prototypes and not more to the prototypes as a whole. The load was applied in an incremental mode, and this type of non-linear analysis produced the results called in the text of Branson discretized and CEB-90 discretized. In the third analysis, with the help of the ANSYS®, and using the incremental load, for each finite element, the expressions of the stiffness associated to the states I and II, that depends on the cracking moment and the maximum bending moment that acts in each finite element, were applied. These results were called in the text of Ansys States I and II. For the mentioned analyses, both the calculated and the experimentally observed cracking moment values were used. Also there was analysed the behavior of the neuter line. Considering the Service Limit State, the methods of Branson, of the CEB-90, the CEB-90 discretized and of Ansys States I and II presented satisfactory results, on behalf of the security, since the calculated cracking moment is used. But when the experimentally cracking moment is used... (Complete abstract click electronic access below)
32

Projeto e execução de lajes unidirecionais com vigotas em concreto armado. / Design and construction of concrete pre-cast slabs with unidirectional ribs.

Flório, Márcio Cardozo 12 December 2003 (has links)
Made available in DSpace on 2016-06-02T20:09:09Z (GMT). No. of bitstreams: 1 DissMCF.pdf: 5555866 bytes, checksum: 149f622dfa87bd0ca10ddd24bfe7b9c5 (MD5) Previous issue date: 2003-12-12 / Financiadora de Estudos e Projetos / This work presents design and executive procedures for pre-cast slabs with unidirectional ribs, which are one of the most used construction elements for small buildings in the country, discussing aspects related to constructive details and both to limit state and service limit design procedures. Many construction details are discussed, such as choice of adequate concrete strength, placement, consolidation and cure of concrete, materials quality assurance tests, formwork, minimum distance between supports to different kinds of joists, camber details and others. Regarding the design procedure, there is study about the consideration of cracking and creep in the deflections service state design and also about shear and flexure reinforcement limit state design. Considerations related to panel continuity and walls directly supported by the slab were taken into account. Special care was taken during the work in other to try to suit design theories to construction techniques already known and used in large scale. Recommendations included in the new concrete code NBR 6118 (2003) were also analyzed. The tests presented were performed mainly by Grupo de Estudos de Sistemas Estruturais em Concreto da UFSCar in which the author belongs in, including a series of tests to measure deflections in pre-cast slab taking in account the creep and cracking phenomena. / Neste trabalho é apresentada toda a metodologia para o projeto e a execução de lajes pré-moldadas com nervuras unidirecionais, que são um dos elementos construtivos mais utilizados em edificações de pequeno porte no país, abordando temas relacionados desde detalhes construtivos assim como o cálculo no estado limite de deformação excessiva. São discutidos detalhes construtivos como a escolha do concreto com resistência adequada, técnicas de cura e adensamento, ensaios necessários no canteiro, lançamento do concreto, cuidados na confecção de formas, distancia mínima entre escoras para diferentes tipos de vigotas, utilização de contra flecha. Em relação ao dimensionamento tem-se a consideração da fissuração e da fluência no estado limite de deformação excessiva e estado limite ultimo de flexão e cisalhamento. São feitas ainda considerações a respeito da continuidade, paredes apoiadas diretamente sobre a laje. Preocupou-se em adequar todas as teorias de cálculo e técnicas já conhecidas e empregadas em larga escala. Estão incluídas neste trabalho as especificações normativas referentes à NBR 6118/03 que acaba de entrar em vigor. Os resultados apresentados foram realizados, em sua maioria, pelo Grupo de Estudo de Sistemas Estruturais em Concreto da UFSCar do qual faz parte o autor dessa dissertação e envolveram uma serie de experimentos relacionados à deformação de lajes pré-moldados considerando os fenômenos de fluência e fissuração do concreto.
33

Análise numérica de lajes treliçadas pré-moldadas com adição de resíduo de borracha /

Santos, Marcos Rebuá dos. January 2009 (has links)
Resumo: Neste trabalho, resultados experimentais relacionados a flechas imediatas de protótipos de lajes pré-moldadas treliçadas biapoiadas, com concreto com e sem resíduo de borracha de pneu, são comparados com resultados numéricos obtidos com base nas recomendações da NBR 6118 (ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS - ABNT, 2003) e do CEB-90 (COMITÊ EURO-INTERNACIONAL DU BÉTON - CEB, 1993). Foram feitas as seguintes análises. Na primeira, aplicaram-se as recomendações dos códigos ao elemento estrutural como um todo visando avaliar a sua rigidez; em seguida, com a expressão procedente da resistência dos materiais, foi calculada a flecha imediata. Estas modelagens numéricas estão referenciadas no texto como Branson, que representa a modelagem adotada pela NBR 6118:2003, e CEB-90. Na segunda, com o auxílio do sistema computacional ANSYS®, as expressões para o cálculo da rigidez segundo os códigos foram aplicadas aos elementos finitos que compunham os protótipos e não mais aos protótipos como um todo. Levou-se em consideração o carregamento incremental e este tipo de análise não linear gerou os resultados referenciados no texto como Branson discretizado e CEB-90 discretizado. Em uma terceira análise, com o auxílio do ANSYS®, utilizando-se o modo de carregamento incremental, aplicou-se, para cada elemento finito, a expressão do momento de inércia relativa aos estádios I ou II, dependendo do máximo momento fletor atuante no elemento e do momento de fissuração do protótipo. Os resultados obtidos foram referenciados no texto como Ansys - Estádios I e II. Para as análises mencionadas, foram utilizados os momentos de fissuração calculados, bem como os momentos de fissuração observados experimentalmente. Também foi analisado o comportamento da linha neutra. Considerando-se o Estado Limite de Serviço, os métodos de Branson, do CEB-90, do CEB-90... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: In this work, experimental results related the immediate displacements of bi-supported lattice joist precast slab prototypes, with and without tire rubber residue in the concrete, are compared with numerical results obtained by the expressions of Branson, which is used by the brazilian standard NBR 6118 (ABNT, 2003), and by the method of CEB-90 (1993). The following analyses were made. In the first analysis, the expressions of the codes were applied for the whole structural element, obtaining its stiffness; so, with the use of the expression from the strength of materials, the immediate displacement was determined, called in this work of Branson and CEB-90. In the second analysis, with the help of the computational system ANSYS ®, the expressions for the calculation of the stiffness according to the codes were applied to the finite elements that were composing the prototypes and not more to the prototypes as a whole. The load was applied in an incremental mode, and this type of non-linear analysis produced the results called in the text of Branson discretized and CEB-90 discretized. In the third analysis, with the help of the ANSYS®, and using the incremental load, for each finite element, the expressions of the stiffness associated to the states I and II, that depends on the cracking moment and the maximum bending moment that acts in each finite element, were applied. These results were called in the text of Ansys States I and II. For the mentioned analyses, both the calculated and the experimentally observed cracking moment values were used. Also there was analysed the behavior of the neuter line. Considering the Service Limit State, the methods of Branson, of the CEB-90, the CEB-90 discretized and of Ansys States I and II presented satisfactory results, on behalf of the security, since the calculated cracking moment is used. But when the experimentally cracking moment is used... (Complete abstract click electronic access below) / Orientador: Jorge Luís Akasaki / Coorientador: José Luiz Pinheiro Melges / Banca: Renato Bertolino Junior / Banca: Roberto Chust Carvalho / Mestre
34

Otimização de componentes de concreto pré-moldado protendidos mediante algoritmos genéticos / Optimization of precast prestressed elements using genetic algorithms

Vanessa Cristina de Castilho 13 February 2003 (has links)
Este trabalho trata da otimização de painéis alveolares e vigotas protendidas utilizando Algoritmos Genéticos (AGs). A proposta de tal algoritmo foi inspirada no princípio da seleção natural de indivíduos, onde o mais ‘apto’ tende a permanecer na população e se reproduzir, passando seu código genético para a próxima geração. Em alguns casos, esse método pode alcançar melhores soluções se comparados aos métodos tradicionais de otimização. O principal objetivo do trabalho é investigar o uso de AG como uma técnica para a minimização da função custo da aplicação de painéis alveolares e vigotas protendidas. Na análise estão incluídas as verificações dos elementos nas etapas transitórias referentes à produção, transporte e montagem. A função custo é avaliada considerando valores da realidade brasileira. O trabalho de pesquisa compara os resultados obtidos utilizando AGs com aqueles obtidos utilizando o método de otimização convencional conhecido como método do Lagrangiano Aumentado. Os resultados obtidos por ambos os métodos evidenciam a eficácia dos AGs com relação ao método convencional. Foram propostas e analisadas três famílias do AG simples, buscando identificar, dentre seus elementos, quais variantes mais adequados na busca da solução dos problemas. / This work aims to optimize the production cost of hollow core panels and prestressed joists using Genetic Algorithms (GAs). The proposal of such an algorithm was inspired by the principle of natural selection of individuals, where the most ‘capable’ tends to remain in the population and reproduce, passing its genetic code onto the next generation. In some cases, this method can achieve good solutions when compared with conventional methods of optimization. The main goal of the work is to investigate AG as a technique for the minimization of the function cost of hollow core panel and prestressed joist applications. The analysis takes account of the verifications of the precast elements in the transitory stages as production,transportation and erection. The function cost is evaluated within the Brazilian context. The research compares the results using GAs with those using a conventional method, the Augmented Lagrangian. The results provide evidence the effectiveness of the GAs with relation to a conventional method. The research considers three families of the simple GA, searching to identify, among them, the adjusted variant in the search of the solution of the problems.
35

Análise teórica e experimental de vigas de madeira de seção transversal \"I\" para uso em fôrmas para concreto / Theoretical and experimental analysis of wood I-beams for formwork purpose

Cátia da Costa e Silva 17 May 2010 (has links)
Devido à importância da madeira na construção civil e a preocupação com o impacto ambiental, a engenharia passou a se preocupar com a racionalização de seu uso por meio da apresentação de produtos engenheirados, buscando melhorar as propriedades técnicas das construções em madeira. Novos modos de manufatura foram introduzidos, principalmente no campo da engenharia estrutural, fazendo com que se desenvolvessem elementos comprovadamente superiores em suas propriedades físico-químicas e econômicas a outros normalmente usados. Neste trabalho foram avaliadas as propriedades de resistência e elasticidade de vigas de madeira de seção transversal \"I\", utilizadas na sustentação de painéis de fôrmas para concreto armado e em obras civis estruturais, incluindo as emendas de mesas e alma-mesa utilizadas em sua fabricação, por meio de ensaios de flexão e cisalhamento na linha de cola. Essas vigas são comercialmente chamadas de H2O devido a sua altura de 20 centímetros, sendo compostas de mesa em madeira serrada, almas em compensado sarrafeado, compensado laminado ou madeira serrada, e dois tipos de adesivos o de poliuretano e o de resorcinol-formol. As análises visaram comprovar a eficiência e viabilidade técnica da fabricação e utilização destes materiais nestas vigas. A configuração de viga H2O que apresentou os melhores resultados comparativamente com o mínimo exigido nos ensaios especificados pela norma européia EN 13377:2002 foi a composta por alma de compensado, emenda dentada e colada com o adesivo de Resorcinol-Formol. / Due to the importance of wood in construction and the concern about the environmental impact, engineers have worried about the rationalization of its use through the development of engineered products, seeking the improvement of the technical properties. In this study, the I-beams built with reforestation wood were used for concrete formwork purpose. Their mechanical properties and the connections between flanges and web used in its manufacture were evaluated by means of bending tests and shear in the glue line. These beams are commercially called H2O. The flanges were made from Pinus Oocarpa, the webs were made from laminated plywood, block plywood, and Pinus Oocarpa, and two types of adhesives were used: polyurethane and resorcinol-formaldehyde. The H2O beam configuration showed the best results compared to the minimum required by European standard EN 13377:2002 was with the flange made from lumber, glued with resorcinol-formaldehyde and the web of laminated plywood.
36

Análise estrutural de lajes formadas por elementos pré-moldados tipo vigota com armação treliçada / Structural analysis of slabs made by precast elements type lattice joist

Alonso Droppa Júnior 26 March 1999 (has links)
Neste trabalho é enfocada a análise estrutural de lajes pré-moldadas formadas por vigotas treliçadas. Esta análise foi realizada mediante o modelo de grelha, considerando a não-linearidade do concreto armado utilizando-se a relação momento x curvatura e carregamento incremental. O modelo da não-linearidade do concreto armado foi avaliado com resultados experimentais de vigas bi-apoiadas e painéis de laje contínua. O trabalho inclui uma análise teórico-experimental de uma laje pré-moldada bidirecional isolada e simulações numéricas de casos representativos de arranjos estruturais das lajes treliçadas. As principais conclusões do trabalho foram: a) o modelo de grelha é bastante adequado para a análise de lajes nervuradas pré-moldadas; b) os resultados da análise teórico-experimental da laje pré-moldada indicam que os deslocamentos foram fortemente influenciados pela rigidez à torção e c) a redistribuição de momentos fletores nas lajes contínuas é relativamente pequena. / This work aims the structural analysis in precast slabs made by lattice joist. The scheme was carried out by using the grillage model considering the non-linear of the reinforced concrete through the relationship moment x curvature and incremental loads. The non-linear model of the reinforced concrete was appraised with experimental of simply supported beams and panels of continuos slabs. The work includes a theoretical-experimental analysis of a isolated bidirectional precast slabs and numeric simulations of representative cases of structural arrangements of the slabs witch lattice joist. The main conclusions of the work were: a) the grillage model is quite appropriate for precast ribbed slabs; b) the results of theoretical-experimental analysis of the precast slabs point out the relevance the torsional in the deflections and c) the bending moments redistribution in the continuous slabs are quite small.
37

Investigation of Shear Lag and Eccentric Weld Demands on Top Chord Knife Connections in Open Web Steel Joist Girders

Walimbe, Anmol 05 October 2021 (has links)
No description available.
38

Nákupní centrum ve Frýdku-Místku / Shopping center in Frýdek-Místek

Pešák, Radek January 2019 (has links)
The aim of the diploma thesis is to construct a steel shopping mall hall. The construction is located in Frýdek-Místek. The whole object can be divided in two parts. One part of the building is an atrium with a cross bridge made from glass. The roof construction of the atrium is designed as system of cylindrical lattice girders within purlins are set up. The other part of the construction is multistoried shopping mall with terrace designed as composite steel and concrete structure. The whole ground plan size of the construction is 72 m x 120 m. The height of the construction above the ground is 12.06 m. The cross-links are built up to 6 m one. There were created two versions of the construction. The most convenient version is described in more details. The outcome of the thesis is a comparison of two above mentioned versions. The whole project is based on officially recognised standard ČSN EN. The construction was designed in RFEM programme.
39

OEKO-ID - Innendämmungen zur thermischen Gebäudeertüchtigung: Untersuchung der Möglichkeiten und Grenzen ökologischer, diffusionsoffener Dämmsysteme: Endbericht Oktober 2013

Ruisinger, Ulrich, Ettenauer, Jörg, Plagge, Rudolf, Hengsberger, Herwig January 2013 (has links)
Das Projekt OEKO-ID hat zum Ziel. problematische Bauteilanschlüsse, insbesondere Balkenköpfe von Holzdecken, im Zusammenhang mit "ökologischen" Innendämmsystemen messtechnisch zu untersuchen. Des Weiteren sollen Möglichkeiten und Grenzen der hygrothermischen Simulation aufgezeigt werden. Ferner wurde eine neue Methode molekularbiologischer und baubiologischer Untersuchungen, hier zur Detektierung von Schimmelpilzen, entwickelt und optimiert.:Inhaltsverzeichnis 1 Technisch-wissenschaftliche Beschreibung der Arbeit 4 1.1 Projektabriss 4 2 Testhaus und energetische Sanierung 6 2.1 Literaturrecherche 6 2.2 Auswahl der Dämmsysteme 7 2.3 Planung Versuchsgebäude 8 2.4 Adaptierung Versuchsgebäude 8 2.5 Vorbereitende Arbeiten 2.7 Montage der Dämmsysteme 14 2.8 Baupraktische Erfahrungen im Spiegel des WTA-Merkblatts E-8-14 18 2.9 Beschreibung der verwendeten Dämmsysteme 20 2.10 Bewertung der verwendeten Dämmstoffe bezüglich der Verarbeitung 26 2.11 Vergleich der Dämmsysteme bezüglich OI3- Index 29 2.12 Erfahrungen beim Rückbau und der Entsorgung 31 2.13 Zusammenfassung der Eigenschaften der Dämmsysteme 39 2.14 Reduzierung der Transmissionswärmeverluste durch Innendämmmaßnahmen 41 3 Hygrothermische Materialkennwerte und -funktionen 43 3.1 Materialuntersuchungen 43 3.2 Beprobung . 44 3.3 Messverfahren 45 3.4 Verifizierungsexperimente: kontinuierliche Wasseraufnahme und Abtrocknung 52 3.5 Erstellung von Materialfunktionen 53 3.6 Zusammenfassung der Eigenschaften der Materialien und Innendämmsysteme 62 4 Mikrobiologische Untersuchungen und Methodenentwicklung 67 4.1 Vorgehen 67 4.2 Ergebnisse 75 5 Hygrothermische Vor-Ort-Messungen 81 5.1 Auswertung der Messdaten 81 5.2 Außen- und Raumklima 82 5.3 Temperatur und Luftfeuchte auf der Bestandsoberfläche 94 5.4 Temperatur und Luftfeuchte in der Mitte der Balkentasche 105 5.5 Temperatur und Luftfeuchte vor dem Stirnholz 109 5.6 Holzfeuchtemessungen 115 5.7 Oberflächentemperaturen 121 5.8 Temperatur- und Feuchteprofile an den Balken 125 5.9 Abdichtung der Balkenauflagertaschen 140 5.10 Mögliches Schimmelpilzwachstum in den Balkenauflagern 147 5.11 Konvertieren und Auswerten der Messungen 149 5.12 Resümee der hygrothermischen Messungen 149 6 Hygrothermische Simulationen 152 6 Hygrothermische Simulationen 152 6.1 Verwendete Simulationsprogramme 152 6.2 Temperatur-Korrektur der Holzfeuchtesensoren 154 6.3 Einfluss von Schlagregen 158 6.4 Berücksichtigung der Permeabilität der Baumaterialien 162 6.5 Simulation der Messergebnisse 166 6.6 Simulation der Grenzschicht Dämmsystem/ Bestandskonstruktion 168 6.7 Simulation eines Balkenkopfs 170 7 Dissemination - Darstellung der Verbreitungs- und Verwertungsmaßnahmen 174 7.1 Workshops 174 7.2 Zusammenarbeit mit anderen Projekten 175 7.3 Vorträge auf (Fach-)Tagungen und Konferenzen 175 7.4 Publikationen 178 8 Zusammenfassung 180 8.1 Technologische und ökologische Bewertung der Dämmsysteme 180 8.2 Bestimmung der Materialeigenschaften 181 8.3 Mikrobiologische Untersuchungen und Methodenentwicklung 181 8.4 Hygrothermische Vorortmessungen182 8.5 Hygrothermische Simulationen 183 8.6 Dissemination 184 9 Literaturverzeichnis 185 10 Unterschrift 192 A1 Anhang zum Abschnitt 2 Versuchsaufbau 193 A2 Anhang zum Abschnitt 4 - Mikrobiologische Untersuchungen 194 A3 Abdruck der Publikationen in internationalen wissenschaftlichen Zeitschriften 208 A4 Bauteilkatalog 230 A5 Monatliche Klima-Durchschnittswerte 247
40

Low Frequency Impact Sound in Timber Buildings : Simulations and Measurements

Olsson, Jörgen January 2016 (has links)
An increased share of construction with timber is one possible way of achieving more sustainable and energy-efficient life cycles of buildings. The main reason is that wood is a renewable material and buildings require a large amount of resources. Timber buildings taller than two storeys were prohibited in Europe until the 1990s due to fire regulations. In 1994, this prohibition was removed in Sweden.     Some of the early multi-storey timber buildings were associated with more complaints due to impact sound than concrete buildings with the same measured impact sound class rating. Research in later years has shown that the frequency range used for rating has not been sufficiently low in order to include all the sound characteristics that are important for subjective perception of impact sound in light weight timber buildings. The AkuLite project showed that the frequency range has to be extended down to 20 Hz in order to give a good quality of the rating. This low frequency range of interest requires a need for knowledge of the sound field distribution, how to best measure the sound, how to predict the sound transmission levels and how to correlate numerical predictions with measurements.     Here, the goal is to improve the knowledge and methodology concerning measurements and predictions of low frequency impact sound in light weight timber buildings. Impact sound fields are determined by grid measurements in rooms within timber buildings with different designs of their joist floors. The measurements are used to increase the understanding of impact sound and to benchmark different field measurement methods. By estimating transfer functions, from impact forces to vibrations and then sound pressures in receiving rooms, from vibrational test data, improved possibilities to correlate the experimental results to numerical simulations are achieved. A number of excitation devices are compared experimentally to evaluate different characteristics of the test data achieved. Further, comparisons between a timber based hybrid joist floor and a modern concrete floor are made using FE-models to evaluate how stiffness and surface mass parameters affect the impact sound transfer and the radiation.     The measurements of sound fields show that light weight timber floors in small rooms tend to have their highest sound levels in the low frequency region, where the modes are well separated, and that the highest levels even can occur below the frequency of the first room mode of the air. In rooms with excitation from the floor above, the highest levels tend to occur at the floor levels and in the floor corners, if the excitation is made in the middle of the room above. Due to nonlinearities, the excitation levels may affect the transfer function in low frequencies which was shown in an experimental study. Surface mass and bending stiffness of floor systems are shown, by simulations, to be important for the amount of sound radiated.     By applying a transfer function methodology, measuring the excitation forces as well as the responses, improvements of correlation analyses between measurements and simulations can be achieved / <p>Opponent:Kari, Leif, Professor</p><p>Handledare: Linderholt, Andreas, Lektor</p><p>ProjektProWoodSilent Timber BuildUrban TranquilityBioInnovation FBBB</p><p>Forskningsfinansiär: KK-stiftelsen</p><p>Delarbeten:</p><p>1. Low frequency measurements of impact sound performance in light weight timber frame office buildings</p><p>2. Low frequency sound pressure fields in small rooms in wooden buildings with dense and sparse joist floor spacings</p><p>3. Low Frequency Force to Sound Pressure Transfer Function Measurements Using a Modified Tapping Machine on a Light Weight Wooden Joinst Floor4. Impact evaluation of a thin hybrid wood based joist floor</p>

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