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This thesis concerns the noise nuisance that results from the operation of urban railways and reports on a case-study of the impact of the Tyneside Metro on residents living in close proximity to the railway tracks. The study was based upon parallel related surveys in the vicinity of Wallsend and Walkergate, during the period August to November 1983: one, a subjective questionnaire survey of perceived noise-nuisance and the other, an objective set of measurements of the actual noise conditions prevailing there. A review of the methods of current practice in the control or urban railway noise demonstrates that regular maintenance of the rails and train wheels is still the most effective way of keeping noise under control at source. Nevertheless, with high speeds of operation, considerable noise nuisance is likely to be experienced by residents nearby. The Metro is the biggest source of noise and noise-nuisance for people exposed to noise levels of over 60 18H Leq dB(A), although the noise annoyance model constructed from the data showed that half of the annoyance felt by respondents could not be explained. Other factors which affect annoyance include vibration, perception of other transport noises, the subjects' ages and whether or not they own the property they occupy. Metro is generally perceived to be quieter and to cause less vibration than the diesel trains (DMUs) which preceded it. The equivalent continuous noise level (Leq) appears to be the most practical of all the various noise indexes for measuring railway noise annoyance. Finally, informal conversation with respondents in the course of a social survey can provide valuable insight into the mental and psychological processes of perception.

The rapid expansion of major cities in the west Europeancountries has accentuated the need to exploit every potentialsite for new establishments, e.g. areas over train tunnels andnear railway tracks in general. A significant impediment toexploit such areas is the structure-borne noise generated bythe train traffic, which is transmitted into buildings via theground. Reliable prediction methods and cost-effective noisecontrol measures are therefore needed and are also the objectof the present work. In this thesis, the studied buildings areconsidered as wave-guides for the sound transmitted from theground. The work is restricted to the case of hard ground suchas granite. The chosen technique permits comparison betweendifferent potential measures to reduce the transmission ofstructure-borne sound upward in buildings. It is shown that thedesign of the load-bearing structures is important in thiscontext, and a design with relocated columns has givenpromising results. It is also shown that the stiffness of theground plays an important role in the transmission process.This leads to the idea that a sand layer between the foundationof the building and the bedrock may reduce the transmission.New methods have thus been developed in the course of this workto evaluate the stiffness of the layer using approximate andexact techniques. Results are presented and a comparison ismade with previous results for a "normal" building and it isshown that the insertion of sand layer has a potential toconsiderably reduce the sound level in the building. <b>Keywords:</b>Ground-borne noise, railway noise, in-planewaves, wave-guides, scattering, propagation constant, inputmobility, elastic stratum, dual integral equations.

<p>The rapid expansion of major cities in the west Europeancountries has accentuated the need to exploit every potentialsite for new establishments, e.g. areas over train tunnels andnear railway tracks in general. A significant impediment toexploit such areas is the structure-borne noise generated bythe train traffic, which is transmitted into buildings via theground. Reliable prediction methods and cost-effective noisecontrol measures are therefore needed and are also the objectof the present work. In this thesis, the studied buildings areconsidered as wave-guides for the sound transmitted from theground. The work is restricted to the case of hard ground suchas granite. The chosen technique permits comparison betweendifferent potential measures to reduce the transmission ofstructure-borne sound upward in buildings. It is shown that thedesign of the load-bearing structures is important in thiscontext, and a design with relocated columns has givenpromising results. It is also shown that the stiffness of theground plays an important role in the transmission process.This leads to the idea that a sand layer between the foundationof the building and the bedrock may reduce the transmission.New methods have thus been developed in the course of this workto evaluate the stiffness of the layer using approximate andexact techniques. Results are presented and a comparison ismade with previous results for a "normal" building and it isshown that the insertion of sand layer has a potential toconsiderably reduce the sound level in the building.</p><p><b>Keywords:</b>Ground-borne noise, railway noise, in-planewaves, wave-guides, scattering, propagation constant, inputmobility, elastic stratum, dual integral equations.</p>

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-09-04T12:58:08Z No. of bitstreams: 1 guilhermevallelouresbrandao.pdf: 12401220 bytes, checksum: 9bc0af060b36cbc30fae487ed61aa6cd (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-09-04T13:24:55Z (GMT) No. of bitstreams: 1 guilhermevallelouresbrandao.pdf: 12401220 bytes, checksum: 9bc0af060b36cbc30fae487ed61aa6cd (MD5) / Made available in DSpace on 2018-09-04T13:24:55Z (GMT). No. of bitstreams: 1 guilhermevallelouresbrandao.pdf: 12401220 bytes, checksum: 9bc0af060b36cbc30fae487ed61aa6cd (MD5) Previous issue date: 2018-03-28 / A ambiência acústica dos lugares é fator preponderante para o adequado desempenho laboral, intelectual ou simplesmente vivencial do ser humano. O local de vivência, se possuir fatores que potencializam a percepção da ambiência acústica, tais como ruído de tráfego, pode causar estresse fisiológico, contribuindo para uma avaliação qualitativa desfavorável do espaço urbano. O objeto de estudo desta pesquisa é o conjunto de características acústicas inerentes às linhas ferroviárias, que se materializam no espaço segundo esses preceitos e os irradiam ao entorno. A presença dessas linhas na malha urbana da cidade de Juiz de Fora – MG – influi diretamente na produção do espaço e direciona vetores de crescimento e valoração do solo, representando um importante aspecto a ser considerado nas políticas de produção da cidade. Este trabalho tem por objetivo identificar as características acústicas ao longo das linhas ferroviárias e suas especificidades, propondo alternativas para mitigação dos problemas verificados nas áreas adjacentes. O recorte desta pesquisa, que se insere no campo da acústica ambiental, se dá pela delimitação de estudo das características acústicas das linhas férreas, focando nas características sonoras das áreas habitadas lindeiras à faixa de domínio na malha urbana de Juiz de Fora. Com relação à metodologia de desenvolvimento, utiliza-se a Revisão Sistemática de Literatura – RSL – para definição do arcabouço teórico referencial e, para realização do estudo de caso, utiliza-se a metodologia proposta pelos referenciais normativos, através de medições in loco. O trabalho se desenvolve em seis capítulos que englobam os conhecimentos necessários à sua realização, focando na aplicação dos conceitos ao ambiente ferroviário. As análises realizadas demonstram que o ambiente acústico ao longo da linha ferroviária é drasticamente impactado pela passagem das composições, provocando o aumento do nível de ruído equivalente para além dos parâmetros normativos de conforto. A partir da situação existente, propõe-se a implantação de um misto de dispositivos convencionais e não convencionais para a redução do ruído, focando em soluções que mantenham permeabilidade visual e busquem reduzir a segregação espacial, gerando resultados que podem ser replicados em outras áreas urbanas, tanto na cidade de Juiz de Fora quanto em outras cidades. Conclui-se que a utilização dos dispositivos de proteção auxilia consideravelmente na redução do nível de pressão sonora equivalente nas áreas lindeiras, entretanto, percebe-se que é necessário o atendimento das edificações do entorno às normas construtivas para mitigação mais eficaz do problema. / Acoustic ambience is a predominant factor for adequate performance levels of work, intellect or simply experiential tasks for human beings. The vivency place itself, when possessing factors that enhance the acoustic ambience perception such as traffic noise can cause physiological stress, contributing to an unfavorable qualitative assessment of the urban space. This research’s object of study is the set of acoustic characteristics inherent to the railway lines, which materialize in space according to these precepts and radiate towards the surroundings. The presence of these railways in the Juiz de Fora city – MG – urban network directly influences the spatial production and directs land growth and valuation vectors, representing an important aspect to be considered in the city's production policies. This work aims to identify the acoustic characteristics along the railway lines and their specificities, proposing alternatives to mitigate problems observed its adjacent areas. The research clipping, which is inserted in the environmental acoustics’ field, is given by binding the study to the railway lines acoustic characteristics, focusing on the inhabited areas neighboring to the railway’s domain range sound characteristics in the Juiz de Fora city’s urban mesh. Regarding the development methodology, the systematic revision of literature method– RSL – is used to define the reference theoretical framework and, to carry out the case study, the methodology proposed by the current normative references is used, through on-the-spot measurements. The work develops in six chapters that encompass the knowledge necessary for its realization, focusing on the concept application to the railway environment. The analyses performed shows that the acoustic environment along the railway line is drastically impacted by the rail compositions passages, causing an increase in the equivalent noise level beyond the normative comfort parameters. From the existing situation, it is proposed to implement a mixture of conventional and non-conventional devices for noise reduction, focusing on solutions that maintain visual permeability and seek to reduce spatial segregation, generating results that can be replicated in other urban areas, both in Juiz de Fora and other cities. It is concluded that using protection devices greatly assists in reducing the equivalent sound pressure levels in the railway’s neighboring areas. However, it is understood that it is necessary for the surrounding buildings to meet the constructive norms for a more effective problem mitigation.

Railway noise is a very important and growing health hazard in today´s society.Railway systems pass through towns and cities and create noise. When trainsride through or over railway bridges, switches and crossings the noise increasessubstantially, causing great annoyance to the residents in the area.At the present time, acoustic regulations exist in most countries and are set to achievea good environmental quality in residential areas, schools, hospitals, offices andhotels.A few calculation models exist for railway traffic noise, such as The NPM 1996,NORD2000 and Cnossos-EU. The NPM 1996 is currently used in Sweden to calculatenoise propagation from railway traffic. To uphold the regulations set, it is importantthat the method used is as precise as possible. All of these calculation modelsare based on several correction factors. Today, the current corrections for trackconditions, that is railway bridges, switches and crossings, are not very accurate andneed to be reconsidered.The aim of this project was to investigate and quantify the error of the NPM correctionfactors and give some indication of how they should be adjusted. This is done to makethe noise prediction from railway traffic more accurate and thus protect the residentsfrom these health risks.The specific objective was to perform significant amount of field measurements ofnoise from trains on different steel bridges, switches and crossings, as well as on afew concrete bridge according to the measurement standard Nordtest NT 098. Thefield work was carried out over the period March to May, when weather conditionsmet the criteria for field measurements, in and around the Stockholm area.The results obtained revealed that the correction factors for steel bridges andcrossings are considerably lower in the NPM than measured in this project. However,the correction factors for switches and concrete bridges are similar to the ones inthe NPM. In this thesis, a part of the correction factors have only been invalidatedto a degree. It has been shown that each bridge is unique and perhaps there is apossibility of finding similarities between some type of bridges. However, much moreiv |measurements are needed to see any correlation between each bridge type. Thus,further and more comprehensive measurements have to be carried out in order toestablish new accurate correction factors for track conditions in the Nordic PredictionMethod.

Le bruit de roulement est la principale source de bruit des transports ferroviaires pour des vitesses conventionnelles. Il est produit par les vibrations puis le rayonnement acoustique du matériel roulant et de la voie provoqués par le déplacement de la roue et du rail. Ce déplacement est imposé par les défauts microscopiques de surface présents sur les bandes de roulement appelés rugosité.La directive Européenne 2002/49/CE exige la réalisation la cartographies du bruit des infrastructures de transport. Le bruit dans l’environnement peut être prédit par des modèles dont les paramètres d’entrées sont notamment le comportement dynamique de la voie et la rugosité des rails. Ces données sont généralement évaluées par des systèmes de mesures statiques, ce qui limite la caractérisation de la voie à quelques dizaines ou centaines de mètres.Cette thèse a pour objectif de proposer et de valider une méthodologie de mesure de l'état acoustique de la voie sur l’ensemble du réseau. La solution proposée est un système de mesure en situation embarquée nommé LECAV pour « LECture Acoustique de la Voie », qui utilise le bruit rayonné par la voir et par la roue. Leurs gammes de fréquences de rayonnement distinctes permettent de traiter le problème inverse séparément pour la roue et pour le rail, et ceux à partir de l’impédance acoustique.Un modèle vibroacoustique basé sur la méthode des éléments finis et la formulation intégrale de Rayleigh est proposé afin d’estimer l’impédance acoustique de la roue. Pour le rail, les théories des poutres épaisses et des sources ponctuelles élémentaires sont utilisées dans le but de modéliser son impédance acoustique. / The rolling noise is the main source of noise in the railway transport sector at conventional speed. It is produced by the vibration and the acoustic radiation of the vehicle and the railway track, caused by the movement of at the wheel and the rail. These movements are imposed by microscopic irregularities on the rolling surface called roughness.The 2002/49/EC European directive imposes to build noise maps of transport infrastructure. The noise propagating in the environment can be assessed from models whose input parameters are particularly the dynamic behavior of railway tracks and the roughness of rails. These data are generally measured thanks to static systems, which narrow down to the analysis of railway tracks to a few meters.The aim of this Phd is to propose and validate a measurement methodology for the acoustic characterization of tracks for the whole railway network. It is an on-board measurement system named LECAV for "LECture Acoustique de la Voie" in French ("Acoustic reading of railway track") that uses the noise radiated from the wheel and the rail. The respective frequencies ranges of noise emission allow solving the invers problem separately for the wheel and for the rail, and this with the acoustic impedance.

The Swedish law requires a set of noise limit for residential buildings for health and safety. Conventionally, the Nordic Prediction Method (NMT) is used to predict the noise. However Nord2000 and CNOSSOS is going to be introduced to replace NMT. An investigation was made to determine which is more accurate in predicting railway noises, particularly reflected railway noises due to the uncharacteristic result in preliminary test. Compromises were made to recreate the measured scenarios in SoundPLAN 8.1. CNOSSOS features an alternative source model requiring new data on the trains and tracks and therefore unable to be compared. The conversion between NMT and Nord2000 was not successful due to the poor documentation of the method. An equivalent value in octave band was used instead. The result were not conclusive as no correlation was found. This might be partly due to the lacking of source model data in the form of track roughness. Result in reflected sound was not conclusive as well since 2 of 3 cases favour Nord2000 and the remaining one favours NMT. The uncertainty introduced in using of the standards and measurements were also rather large, which is also one of the factor in non correlating results. / Svensk lag kräver en viss uppsättning bullergränser gällande boende i bostadshus för deras hälsa och säkerhet. Konventionellt används den nordiska beräkningsmodellen för tågbuller (NMT) för att förutsäga bullret. Nord2000 och CNOSSOS kommer dock att införas för att ersätta NMT. En undersökning gjordes för att avgöra vilken eller vilka modeller som är mest exakta för att kunna förutsäga järnvägsljud, i synnerhet reflekterade järnvägsljud på grund av tidigare osäkerhet i resultatet i det preliminära testet. Kompromisser gjordes för att återskapa de uppmätta scenarierna i SoundPLAN 8.1. CNOSSOS erbjuder en alternativ modellering men kräver ny data från både tåg och räls och omöjliggjorde därför att kunna jämföras. Konverteringen mellan NMT och Nord2000 lyckades inte på grund av den bristfälliga dokumentationen av metoden. Ett ekvivalent värde i oktavband användes istället. Resultatet var inte definitivt eftersom ingen korrelation upptäcktes. Detta kan delvis bero på bristande källmodelldata i form av spårgrovhet. Resultatet av reflekterat ljud var inte heller definitivt eftersom 2 av 3 fall förespråkar Nord2000 och det återstående förespråkar NMT. Osäkerheten som implementeras vid användning av standarder och mätningar är också av betydande storlek, vilket också är en av faktorerna som härleder korrelerande resultat.

Die Eisenbahn wird in der Öffentlichkeit als umweltfreundliches Verkehrsmittel gesehen und ist für Personen und Fracht die bedeutendste Alternative zum Straßenverkehr. Die hohe Lärmbelastung, die die Bahn jedoch in Ballungsgebieten oder an stark belasteten Strecken verursacht, führt zu Akzeptanzproblemen in der Bevölkerung und zunehmend in der Politik. Eine Steigerung des Schienenverkehrs ist deshalb nur möglich, wenn die Schallabstrahlung der Schienenfahrzeuge in Zukunft spürbar reduziert werden kann. Im Geschwindigkeitsbereich des konventionellen Güter- und Personenverkehrs ist das Rollgeräusch die dominierende Schallquelle. Bei der Rollbewegung wird die Oberflächenrauheit von Rad und Schiene überfahren und wirkt als Erregung in der Kontaktzone. Rad und Schiene werden in Schwingung versetzt und strahlen Schall ab. Ziel dieser Arbeit ist es, einen ausführbaren CAE-Prozess aufzubauen und anzuwenden, der auf dem aktuellen Stand der Modellierungstechnik die Optimierung von Eisenbahnrädern nach akustischen Gesichtspunkten ermöglicht. Der Kernbestandteil dieses Prozesses sind effiziente Methoden, die es ermöglichen, für einen rotationssymmetrischen Radsatz binnen weniger Sekunden die im Rad-Schiene-System abgestrahlte Schallleistung zu berechnen. Die Modellierung der Schwingung und Schallabstrahlung des rotierenden Radsatzes bildet einen Schwerpunkt. Verschiedene Anregungshypothesen und -modelle werden gegenübergestellt und anhand eines Prüfstandsversuchs auf ihre Validität untersucht. Der Anregungsmechanismus des Rollgeräuschs wird aus der Literatur aufgearbeitet und ein Modell für die Schallvorhersage daraus entwickelt. Dabei spielt die Körperschallleistung des Rades eine entscheidende Rolle. Sie kann mit Hilfe der Ergebnisse einer numerischen Modalanalyse sehr schnell und automatisiert berechnet werden und stellt im Falle des Eisenbahnrades eine effiziente und brauchbare Alternative zu aufwendigen BEM-Simulationen dar. Die Wirkung der Rauheit wird mit einem Kontaktmodell untersucht und die Filterwirkung des Kontakts dabei ermittelt. Es werden Studien zur wegerregten Schwingung im Rad-Schiene-System vorgestellt, in denen sich einige Spezifika offenbaren. Nahe seinen Eigenfrequenzen zeigen sich für den Radsatz erwartungsgemäß erhöhte Schwingungsamplituden. Jedoch ist dies keine eigentliche Resonanz sondern ein Effekt von Antiresonanz bzw. Tilgung. Dies führt u. A. dazu, dass eine Erhöhung der Dämpfung zwar die Schwingung vermindert, die Wirkung jedoch weit hinter der unter Krafterregung zu erwartenden Reduktion zurückbleibt. Ein in ANSYS parametrisch modellierter Güterwagen-Radsatz wird hinsichtlich Masse und Schallleistung optimiert. Es zeigt sich ein Verbesserungspotenzial gegenüber beispielhaft gewählten Referenzradsätzen von ein bis drei Dezibel. Ein für den praktischen Einsatz verwendbares, akustisch optimiertes Rad ist im Rahmen der Arbeit nicht entwickelt worden. Der CAE-Prozess stellt jedoch ein Werkzeug dar, die konstruktiven Freiräume bei der Entwicklung von Radsätzen zielgerichtet so auszunutzen, dass hierbei ein möglichst leises Rad entsteht.