Made available in DSpace on 2017-07-10T17:31:12Z (GMT). No. of bitstreams: 1 Wellington_Barbosa_da_Silva.pdf: 4552878 bytes, checksum: cced6a1f2d0a0c2426792ba3f3f8ce33 (MD5) Previous issue date: 2011-07-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / On the Guarapuava Plateau/Palmas, in a low slope hillside of superficial covering from basaltic origins, on the right bank of the Rio das Pombas, Paraná state, processes of tunnel erosion (pipes) were identified. These are subsuperficial erosion processes with typical features, such as subsidence of the tunnel roof and rebate structures, which tend to evolve to superficial features. The emerging of this erosive process depends on a set of factors, being the main one, the properties of the superficial covering, such as: texture, macroporosity, granulometric composition (chemical matter make-up), density, porosity e chemical elements that make up the matter, those concerning the hydrological conditions and the topography of the hillside. In order to recognize and characterize the superficial covering in the sector of low hillside, sieve analysis was used, as well as real and apparent density, total porosity verified; toposequences were made and X-ray scattering techniques performed. The results showed that the matter which covers the low hillside sector, where the tunnels are, have a sandy texture due to the properties of microagregation generated by clay mineral, gibbsite; leaving the matter with a high porosity level, thus favoring the flowing of water through subsurfaces. The generated flows tend to be exfiltrated to a ditch wall-like surface, which causes the removal of small particles of matter (seepage). With the opening of small gullies through subsurface, the flow tend to become concentrated (tunnel scour) and consequently enlarge the subsuperficial channels by the mechanical action of the water. In a sequence of factors that can be used for the analysis of the process generation, which causes: alteration in basalt rocks, microaggregation of the matter, macroporosity and increase of water flow through subsurface. Therefore, the hydrology conditions in the hillside contributed for erosion mechanisms to emerge in subsurface, development of erosion process, formation of subsuperficial erosion and, ultimately, superficial erosion process development. These both chemical and physical features found in such field of study, show that the superficial covering is a determining factor for the subsuperficial tunnel erosion to originate in the hillside. / No Planalto de Guarapuava/Palmas, em encosta de baixa declividade e cobertura superficial de origem basáltica, à margem direita do Rio das Pombas em Guarapuava (Paraná), foram identificados processos de erosão em túneis (pipes). Trata-se de processos subsuperficiais de erosão que apresentam feições típicas, tais como, subsidência do teto do túnel e estruturas de abatimento, que tendem a evoluir para feições superficiais. A instalação desse processo erosivo depende de um conjunto de fatores, destacando-se como condicionantes, as propriedades da cobertura superficial como: textura, macroporosidade, composição granulométrica, densidade, porosidade e constituintes químicos dos materiais, e aqueles relativos às condições hidrológicas e à topografia da encosta. Buscando-se reconhecer e caracterizar a cobertura superficial do setor de baixa encosta, foram realizadas análises granulométricas, de densidade aparente, real e porosidade total, construção de topossequências e análises químicas de difração de raios-X. Os resultados indicaram que o material que recobre o setor de baixa encosta, onde aparecem os túneis, apresenta textura arenosa devido às propriedades de microagregação gerada pelo argilomineral gibbsita, deixando o material com porosidade alta, favorecendo assim a circulação de água em subsuperficie. Os fluxos gerados tendem a ser exfiltrados para uma superfície de exposição, o que provoca a remoção de pequenas partículas de material (seepage). Com a abertura de pequenos canais em subsuperfície, os fluxos tendem a se concentrar (tunnel scour) e consequentemente ampliar os canais subsuperficiais pela ação mecânica da água. Numa sequência de fatores que possam ser postos para análise da geração do processo, têm-se: alteração da rocha basáltica, microagregação do material, macroporosidade e aumento da circulação de água em subsuperfície. Assume-se que as condições hidrológicas da encosta propiciaram a instalação de mecanismos de erosão em subsuperfície, evolução do processo erosivo, formação de feições erosivas subsuperficiais e, por fim, instalação de feições erosivas superficiais. Essas características físicas e químicas encontradas na área de estudo, demonstram que a cobertura superficial é determinante para a instalação da erosão subsuperficial em túneis na encosta.

Made available in DSpace on 2017-05-12T14:42:43Z (GMT). No. of bitstreams: 1 Wellington_Barbosa_da_Silva.pdf: 4552878 bytes, checksum: cced6a1f2d0a0c2426792ba3f3f8ce33 (MD5) Previous issue date: 2011-07-08 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / On the Guarapuava Plateau/Palmas, in a low slope hillside of superficial covering from basaltic origins, on the right bank of the Rio das Pombas, Paraná state, processes of tunnel erosion (pipes) were identified. These are subsuperficial erosion processes with typical features, such as subsidence of the tunnel roof and rebate structures, which tend to evolve to superficial features. The emerging of this erosive process depends on a set of factors, being the main one, the properties of the superficial covering, such as: texture, macroporosity, granulometric composition (chemical matter make-up), density, porosity e chemical elements that make up the matter, those concerning the hydrological conditions and the topography of the hillside. In order to recognize and characterize the superficial covering in the sector of low hillside, sieve analysis was used, as well as real and apparent density, total porosity verified; toposequences were made and X-ray scattering techniques performed. The results showed that the matter which covers the low hillside sector, where the tunnels are, have a sandy texture due to the properties of microagregation generated by clay mineral, gibbsite; leaving the matter with a high porosity level, thus favoring the flowing of water through subsurfaces. The generated flows tend to be exfiltrated to a ditch wall-like surface, which causes the removal of small particles of matter (seepage). With the opening of small gullies through subsurface, the flow tend to become concentrated (tunnel scour) and consequently enlarge the subsuperficial channels by the mechanical action of the water. In a sequence of factors that can be used for the analysis of the process generation, which causes: alteration in basalt rocks, microaggregation of the matter, macroporosity and increase of water flow through subsurface. Therefore, the hydrology conditions in the hillside contributed for erosion mechanisms to emerge in subsurface, development of erosion process, formation of subsuperficial erosion and, ultimately, superficial erosion process development. These both chemical and physical features found in such field of study, show that the superficial covering is a determining factor for the subsuperficial tunnel erosion to originate in the hillside. / No Planalto de Guarapuava/Palmas, em encosta de baixa declividade e cobertura superficial de origem basáltica, à margem direita do Rio das Pombas em Guarapuava (Paraná), foram identificados processos de erosão em túneis (pipes). Trata-se de processos subsuperficiais de erosão que apresentam feições típicas, tais como, subsidência do teto do túnel e estruturas de abatimento, que tendem a evoluir para feições superficiais. A instalação desse processo erosivo depende de um conjunto de fatores, destacando-se como condicionantes, as propriedades da cobertura superficial como: textura, macroporosidade, composição granulométrica, densidade, porosidade e constituintes químicos dos materiais, e aqueles relativos às condições hidrológicas e à topografia da encosta. Buscando-se reconhecer e caracterizar a cobertura superficial do setor de baixa encosta, foram realizadas análises granulométricas, de densidade aparente, real e porosidade total, construção de topossequências e análises químicas de difração de raios-X. Os resultados indicaram que o material que recobre o setor de baixa encosta, onde aparecem os túneis, apresenta textura arenosa devido às propriedades de microagregação gerada pelo argilomineral gibbsita, deixando o material com porosidade alta, favorecendo assim a circulação de água em subsuperficie. Os fluxos gerados tendem a ser exfiltrados para uma superfície de exposição, o que provoca a remoção de pequenas partículas de material (seepage). Com a abertura de pequenos canais em subsuperfície, os fluxos tendem a se concentrar (tunnel scour) e consequentemente ampliar os canais subsuperficiais pela ação mecânica da água. Numa sequência de fatores que possam ser postos para análise da geração do processo, têm-se: alteração da rocha basáltica, microagregação do material, macroporosidade e aumento da circulação de água em subsuperfície. Assume-se que as condições hidrológicas da encosta propiciaram a instalação de mecanismos de erosão em subsuperfície, evolução do processo erosivo, formação de feições erosivas subsuperficiais e, por fim, instalação de feições erosivas superficiais. Essas características físicas e químicas encontradas na área de estudo, demonstram que a cobertura superficial é determinante para a instalação da erosão subsuperficial em túneis na encosta.

O processo de liberação da operação comercial de um túnel rodoviário, sempre é realizada sobre a pressão típica do final de um cronograma, cujo prazo final, está em vias de se esgotar. Por outro lado considerando os relevantes riscos envolvidos com a operação de um túnel, o órgão público que libera o início da operação comercial (Artesp no caso do Estado de São Paulo), deve ter plena certeza que a nova estrutura está pronta a utilização e apresenta-se totalmente preparada a atender os requisitos mínimos de segurança. O presente trabalho propõe uma metodologia de avaliação de conformidade aderente a NBR ISO/IEC 17020:2006 - avaliação de conformidade com os critérios gerais para o funcionamento de diferentes tipos de organismos que executam inspeções. Para tanto foi realizado um extenso e minucioso trabalho de identificação dos requisitos aplicáveis, concatenando as referências internacionais de túneis, o modus operandi nacional e a ferramenta gerenciamento de riscos, que resultaram numa proposta de metodologia de avaliação de conformidade composta por onze atividades, que aplicadas permitem avaliar as condições de liberação ao uso e operação comercial de túneis rodoviários. / The process of releasing the commercial operation of a road tunnel is always done under the typical pressure of a chronogram deadline. On the other hand, considering the relevant risks involved with the tunnel operation, the public institution that releases the beginning of the commercial operation (ARTESP, in the case of São Paulo State), should be totally sure that the new structure is ready to be used and shows it is completely prepared to meet the needs of the minimum security requirements. The present work proposes an evaluation methodology of adherent conformity the NBR ISO/IEC 17020:2006 Conformity evaluation with the general criteria for the functioning of different types of organisms that perform inspections. In order to do so, a large and detailed work of identification of the applicable requirements, linking together the international references of tunnels, national way of working and the tool Management of Risks, that ended in a proposal of conformity evaluation methodology composed by eleven activities, that if applied, allow evaluation of the releasing conditions to the use and commercial operation of road tunnels.

Ce travail se divise en trois parties auxquelles s'ajoute une annexe dans laquelle nous avons placé deux études particulières (étude de hors-profils - étude de microfaciès) ceci pour ne pas surcharger le texte. Dans la première partie, nous exposerons l'étude géologique de projet de la galerie du Bourget qui conduit au profil en long géologique prévisionnel de cet ouvrage. Dans la deuxième partie, nous montrerons l'importance des études géologiques pendant les travaux pour permettre, plusieurs années après l'exécution et le revêtement d'un ouvr age, de comprendre l'origine d ' éventuelles dégradations. La troisième partie résume l'esprit dans lequel a été abordé ce travail en montrant le rôle du géologue aux différents stades d'une étude géologique de souterrain

Cette thèse aborde à la fois des aspects comportementaux et numériques de la réponse mécanique du massif rocheux au creusement d'un tunnel. La comparaison de critères existants a mis l'accent sur quelques points clefs, comme la dépendance du critère à la contrainte moyenne et le ratio d'extension. Une fonction de charge, aisément identifiable à partir des essais, au caractère régulier et convexe, capable de tenir compte de la forme de l'enveloppe de Mohr du critère, ainsi que du ratio d'extension, a été proposée : on peut ainsi réaliser des formes régularisées des critères de Mohr-Coulomb et de Hœk-Brown. Le développement de ce nouveau critère a été complété par la proposition d'une méthode d'abaques numériques, accélérant grandement la résolution. Pour le critère proposé, le problème physique est équivalent à un problème purement géométrique, en coordonnées polaires dans le plan. On peut ainsi constituer des abaques numériques qui permettent d'obtenir directement la valeur des déformations plastiques, ce qui diminue drastiquement le temps de calcul Les méthodes de calcul des tunnels ont fait l'objet d'une synthèse biblio- graphique, précisant les domaines et les limites d'emploi des méthodes utilisées par les ingénieurs pour dimensionner les tunnels. La modélisation du creusement des tunnels a été réalisée à l'aide de l'algorithme stationnaire, conçu pour calculer le comportement de systèmes soumis à des chargements mobiles. Cet algorithme a été programmé pour intégrer le nouveau critère et la méthode des abaques numériques. Les outils ainsi développés ont pu être confrontés à un cas d'étude réel, à partir de données fournies par l'Agence Nationale de Gestion des Déchets Radioactifs (ANDRA) au titre du projet européen MODEX-REP (projet s'insérant dans le cadre du 5e plan EURATOM de la commission européenne). L'étude de ces données a permis de définir une variable de dégradation de la roche, aisément identifiable et permettant de paramétrer le critère pour la roche endommagée.

Contrary to the linings of conventionally driven tunnels, the linings of tunnels bored by tunnel boring machines (TBMs) consist of precast concrete segments which are articulated or coupled at the longitudinal and circumferential joints. There are several analytical and numerical structural analysis methods proposed for the design of TBM segmental linings. In this thesis study, different calculation methods including elastic equation method and two dimensional (2D) and three dimensional (3D) beam &ndash / spring methods are compared and discussed. This study shows that in addition to the characteristics of concrete segments, the mechanical and geometrical properties of longitudinal and circumferential joints have significant effects on the structural behavior of segmental lining.

The goal of this project was to develop a wind generator that utilizes the collective oscillating motion of multiple piezoelectric devices. These devices would be an alternative to rotating turbine designs for low power generation, for use in applications such as remote power generation. A series of inexpensive devices were developed that harvested energy from vortex shedding, both as independent and cooperative devices. The behavior of single devices was studied, but more interestingly, the way that multiple devices arranged together can increase power output was studied. It was shown that individual devices could harvest more energy if they were placed as specific positions relative to the vortices shed by devices upstream. Through investigating the behavior of these devices, fundamental principles of the phenomenon of vortex induced vibrations were explored. Methods were developed to measure the amplitude and frequency of these vibrations in a wind tunnel, through high speed video and correlations that were found between oscillation and power output from the piezoelectric transducers. Similarly, vortex induced vibrations were explored in an approximation of a two dimensional system in a flowing soap film.

published_or_final_version / abstract / toc / Transport Policy and Planning / Master / Master of Arts in Transport Policy and Planning

A new philosophy in structural health monitoring was explored, with the view to the creation of a smart mining bolt: one which would bear the normal load of any bolt used in South African gold mining tunnels, but at the same time be capable of monitoring its own level of damage. To this end, a survey of various smart materials currently used in structural health monitoring applications, was conducted, and a group known as strain memory alloys isolated as holding the most promise in this regard. Strain memory alloys give an indication of peak strain based on an irreversible transformation from paramagnetic austenite to ferromagnetic martensite, which occurs in direct proportion to the amount of strain experienced by the material. A measurement of magnetic permeability can therefore be correlated to peak strain. An extensive study of the alloying chemistry, material processing and transformation characteristics was therefore carried out, including an analytical model for the quantification of the energy associated with martensitic nucleation, at a dislocation-disclination level. The conditions within typical South African gold mining tunnels were evaluated, and a smart mining bolt design produced, based on the loading and environmental conditions present. Several material formulations were then proposed, melted, tested and evaluated against the relevant strength, corrosion and transformation criteria. A suitable material was selected and further tested. A working prototype bolt has been produced, and in situ tests of complete bolts, are scheduled to take place shortly. / Thesis (Ph.D.)-University of Natal, Durban, 2003.

La feina feta en aquest treball de tesis s'ha desenvolupat a partir de tres objectius vertebradors, que fonamentalment són:·El primer dels objectius d'aquest treball de tesis és presentar un recull dels factors que intervenen en l'acústica urbanística: soroll produït pels diferents vehicles, fórmules de predicció de soroll, geometria dels edificis... , tot estudiant els seus efectes en la ciutat de Girona.·Un altre objectiu ha estat desenvolupar uns mètodes numèrics propis, contrastats experimentalment i extrapolables a qualsevol entorn urbanístic, que permetin predir els valors de les pertorbacions acústiques produïdes pels diferents vehicles en diferents situacions, entre els que es destaquen: -Fórmula de predicció del soroll en un entorn urbà i la seva aplicació a Girona.-Càlcul de l'increment de soroll en un carrer provocat per les reflexions de les ones sonores en les façanes dels edificis.-Estudi del nivell de soroll en la boca de la cavitat d'un túnel produït pel pas del ferrocarril.-Determinació del soroll provocat pel pas d'un tren sobre un viaducte.-Mètode de distribució i planificació del trànsit urbà per disminuir l'impacte acústic sobre la zona.·El darrer objectiu consisteix en fer una descripció analítica de les principals fonts de soroll que afecten a la ciutat: el trànsit viari i el ferrocarril.Per realitzar aquests objectius s'ha disposat d'un banc de dades amb més de 2.000 mesures sonores de Girona (nivells equivalents de 10 minuts de durada). La metodologia seguida i els principis en que es fonamenta es detallen a l'inici de cada apartat. La finalitat de tots aquests estudis, no és altre que millorar el confort acústic, i la qualitat de vida, de les ciutats. Gairebé tots els grans nuclis de població del planeta es veuen afectats per una gravíssima problemàtica mediambiental, doncs a l'anomenada contaminació acústica cal afegir uns alts índexs de pol·lució atmosfèrica (altes concentracions de biòxid de carboni, generació d'illes de calor...). Aquesta situació, generalitzada arreu del planeta, ha propiciat l'aparició de mesures dràstiques consistents fonamentalment en restringir l'accés dels vehicles motoritzats als nuclis i zones centrals de les àrees urbanes. Precisament aquesta opció s'ha proposat per les zones interiors de Girona on l'elevada densitat de les edificacions deixa un escàs marge per plantejar la construcció de noves rutes o vies alternatives.Cal esmentar que tots els càlculs i teories que es desenvolupen en aquest treball de tesis reflecteixen la realitat acústica actual provocada pels diferents mitjans de transport. Molt possiblement, en un futur no massa llunyà, els nivells de soroll (dB) enregistrats en situacions de tràfic similar seran força menors. Són molts els factors que poden contribuir a aquesta disminució de la intensitat de les emissions sonores: reducció del fregament mecànic, augment del coeficient aerodinàmic, nous materials pels pneumàtics i l'asfalt ... Sense cap mena de dubte, però, una millora transcendental, i no només pel que fa al confort acústic sinó per l'ecosistema en general, seria potenciar la construcció de motors elèctrics o d'hidrogen. Aquests últims per exemple, a diferència dels motors de combustió, funcionen mitjançant piles de combustible que converteixen, amb molta netedat, el gas hidrogen en electricitat i possibiliten l'existència de vehicles no contaminants propulsats per motors elèctrics menys sorollosos. Així, al haver-hi menys fregament entre les parts mòbils del motor (no hi ha pistons ni cilindres) el soroll generat es reduiria considerablement. / This thesis has been made considering three main objectives:The first one is to explain the main factors involved in noise generation and prediction: traffic and railway noise, noise prediction models, buildings geometry... This study has been applied to the city of Girona.The second objective has been develope our own numerical methods, experimentally contrasted and applicable to any urban area, to predict the noise level produced by the vehicles in different situations.The last objective consist in analize the main noise sources in the city, especially traffic and railway noise.To achieve this objectives a large data bank with approximately 2000 noise measures (equivalent sound levels) has been used. The aim of this work is to improve the quality of life, reducing the sound pressure levels.Almost all the big cities are affected by serious acoustical problems. To the so called "acoustic contamination" there are other, direct or indirectly, related environmental problems like atmospheric pollution levels. This situation is common around the planet and has propitiated the application of several restriction measures applied to traffic flow in certain urban areas. This solution has been proposed and studied from different points of view in the city of Girona.