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Šiuolaikinių tiltų įstabios architektūrinės formos ir tiltų statybos vietos ne visada leidžia pritaikyti dažniausiai naudojamas konstrukcines schemas. Todėl inžinieriams tenka pasinaudoti retesniais, mažiau tyrinėtais tiltų konstrukciniais variantais. Pastaruoju metu pasaulyje, ypač Kinijoje, vėl pradėta naudoti kabamųjų tiltų atmaina – neskėtrieji kabamieji tiltai. Išaugęs tokių tiltų poreikis reikalauja išsamios neskėtriojo kabamojo tilto elgsenos ypatumų analizės. Nuodugniam šios konstrukcinės schemos analizės atlikimui suformuluojamas darbo tikslas – išnagrinėti neskėtriųjų tiltų pradinės analizės metodus, įvairių variantų vienpilonių neskėtriųjų tiltų elgseną veikiant statinei apkrovai. Šiam tikslui pasiekti keliami tokie uždaviniai: 1. Apžvelgti kabamųjų tiltų konstrukcijas, jų projektavimo bei elgsenos ypatumus. 2. Išanalizuoti kabamųjų tiltų analizės metodus, išskiriant neskėtriųjų tiltų skaičiavimo ypatumus. 3. Išanalizuoti vienpilonių neskėtriųjų plieno tiltų elgseną, veikiant simetrinei ir asimetrinei apkrovoms. 4. Kabamojo tilto pradinei formai stabilizuoti pritaikyti baigtinio lenkiamojo standžio elementus. 5. Parinkti neskėtriojo tilto racionalius komponuojamuosius parametrus ir įvertinti neskėtriųjų kabamųjų tiltų panaudojimo galimybes. Darbe taikomas kompiuterinis modeliavimas baigtinių elementų metodu, naudojantis MIDAS Civil programa. Apžvelgiami gauti rezultatai ir pateikiamos išvados bei pasiūlymai. / Wonderful shapes of modern bridges, especially pedestrian, and their construction sites not always let to adapt usual bridge structure. That’s why engineers have to use unusual and less researched structures. Recently in the world, especially in China, other suspended structure is being used – self-anchored suspension bridges. Recently grown popularity of these bridges requires comprehensive self-anchored bridge behavioral analysis. For an extensive analysis accomplishment the objective is stated – to examine initial analysis methods of self-anchored suspension bridges, behavior of various two-span self-anchored bridges subjected to static loading. To achieve this objective, following tasks are raised: 1. Review suspension bridge structures, their analysis and design peculiarities. 2. Analyze calculation methods of suspension bridges, including peculiarities of self-anchored bridge design. 3. Analyze behavior of steel two-span self-anchored suspension bridge subjected to symmetrical and asymmetrical loading. 4. Apply finite bending stiffness elements for main cables to stabilize primer shape. 5. Evaluate self-anchored suspension bridge technical-economic performance. Computer-aided design using finite element program MIDAS Civil is applied in this research. An overview of the results with conclusions and recommendations are presented.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22414号 / 工博第4675号 / 新制||工||1729(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 杉浦 邦征, 教授 河野 広隆, 教授 八木 知己 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18519号 / 工博第3911号 / 新制||工||1601(附属図書館) / 31405 / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 白土 博通, 教授 宮川 豊章, 教授 八木 知己 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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This thesis presents a state-of-the-art-review and twodifferent approaches for solving the moving load problem ofcable-stayed and suspension bridges. The first approach uses a simplified analysis method tostudy the dynamic response of simple cable-stayed bridgemodels. The bridge is idealized as a Bernoulli-Euler beam onelastic supports with varying support stiffness. To solve theequation of motion of the bridge, the finite difference methodand the mode superposition technique are used. The second approach is based on the nonlinear finite elementmethod and is used to study the response of more realisticcable-stayed and suspension bridge models considering exactcable behavior and nonlinear geometric effects. The cables aremodeled using a two-node catenary cable element derived using"exact" analytical expressions for the elastic catenary. Twomethods for evaluating the dynamic response are presented. Thefirst for evaluating the linear traffic load response using themode superposition technique and the deformed dead load tangentstiffness matrix, and the second for the nonlinear traffic loadresponse using the Newton-Newmark algorithm. The implemented programs have been verified by comparinganalysis results with those found in the literature and withresults obtained using a commercial finite element code.Several numerical examples are presented including one for theGreat Belt suspension bridge in Denmark. Parametric studieshave been conducted to investigate the effect of, among others,bridge damping, bridge-vehicle interaction, cables vibration,road surface roughness, vehicle speed, and tuned mass dampers.From the numerical study, it was concluded that road surfaceroughness has great influence on the dynamic response andshould always be considered. It was also found that utilizingthe dead load tangent stiffness matrix, linear dynamic trafficload analysis give sufficiently accurate results from theengineering point of view. / QC 20100511

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Ao contrário da catenária, o estudo da parábola é encontrado com freqüência nos livros didáticos de matemática. Dois livros didáticos foram analisados para esta pesquisa: o livro de Olavo Freire de 1894, que associa o formato do cabo pênsil ao de uma parábola, e o livro da década de 1970 de Osvaldo Sangiorgi, que relaciona à figura de um balanço a forma de uma parábola. Notamos que esses livros didáticos com oitenta anos de diferença usam a corda suspensa para representar a forma parabólica. Como o formato de um cabo suspenso pelas extremidades sob a ação do seu próprio peso é representado pela catenária, sentimo-nos motivados a pesquisar sobre as curvas e entender por quais delas, afinal, o cabo da ponte pênsil é mais bem representado. Visto que essa dúvida surgiu a partir de livros didáticos, discorremos sobre a função do livro de matemática, na sala de aula, como indicadores do ensino da matemática, de um determinado local, dentro de determinado contexto histórico-político. No decorrer da história da matemática, houve confusão entre essas duas curvas, a qual motivou o estudo da catenária a partir do século XVII. Essa fase da história é conhecida como época das curvas, e em 1600, por Huygens, que se iniciaram seus estudos. Examinamos as curvas catenária e parábola no âmbito da educação e da história da matemática, bem como suas propriedades e aplicações práticas no âmbito da engenharia de pontes pênseis e na arquitetura. Amparamo-nos em leituras específicas de construção e história de algumas pontes pênseis e chegamos a visitar a Ponte Estaiada em São Paulo ainda em edificação, para entendermos como os engenheiros utilizam as propriedades das curvas catenária e parábola em sua construção. Os resultados revelaram que, surpreendentemente, o exemplo adotado no livro de Olavo Freire para representar uma parábola não levou em consideração o que acontece na prática da engenharia das pontes pênseis, e o ressurgimento do exemplo do balanço no livro de Osvaldo Sangiorgi, pareceu reforçar a tese de que havia, sim, certa confusão entre as duas curvas. Utilizando o software gráfico Winplot, construímos as curvas catenária e parábola e pudemos visualizar as diferenças ou similaridades entre elas. Finalizando, comprovamos algebricamente a aproximação entre as curvas catenária e parábola e a definição de parábola no ponto de vista da engenharia. / Unlike the catenary, the study of the parabola is often found in textbooks of Mathematics. Two textbooks were analyzed for this research: the book of Olavo Freire, 1894, which combines the format of the cable suspended to a parabola, and the book of the decade of 1970 of Osvaldo Sangiorgi, which relates to the figure of a stock as a parabola. Note that these textbooks with eighty years of difference used the rope suspended to represent the parabolic shape. As the format of a cable suspended by the extremities under the action of its own weight is the catenary, we felt motivated to search on the curves and understand how, after all, the cable of the suspension bridge is best represented. Since this question came from textbooks, we studied the basis of the book of Mathematics in the classroom, as indicators of teaching Mathematics in a given location, within a certain historical and political context. Throughout the history of Mathematics, there was confusion between these two curves, which led the study of catenary from the seventeenth century. This phase of history is known as the curves season, and in 1600, by Huygens, who started their studies. We have audited the catenary curves and parabola in education and the history of Mathematics, and its properties and practical applications in the Engineering of suspension bridges and architecture. Supported us in specific readings of history and construction of some suspension bridges and even payed a visit to the bridge Estaiada in Sao Paulo which is still under construction, to understand how the engineers use the properties of the catenary curves and parabola in its construction. The results showed that, surprisingly, the example used in the book of Olavo Freire to represent a parabola did not bring into account what happens in the practice of Engineering of the suspension bridges, and the resurgence of the example of the balance sheet in the book of Osvaldo Sangiorgi seemed to strengthen the argument that there was some confusion between the two curves. Using the software chart Winplot, the catenary and parabola curves were built and we could visualize the differences or similarities between them. At last, using algebra we proved the rapprochement between the catenary curves and definition of parabola in terms of Engineering.

The field of bridge monitoring is one of rapid development. Advances in sensor technologies, in data communication and processing algorithms all affect the possibilities of Structural Monitoring in Bridges. Bridges are a very critical part of a country’s infrastructure, they are expensive to build and maintain, and many uncertainties surround important factors determining their serviceability and deterioration state. As such, bridges are good candidates for monitoring. Monitoring can extend the service life and avoid or postpone replacement, repair or strengthening works. The amount of resources saved, both to the owner and the users, by reducing the amount of non-operational time can easily justify the extra investment in monitoring. This thesis consists of an extended summary and five appended papers. The thesis presents advances in sensor technology, damage identification algorithms, Bridge Weigh-In-Motion systems, and other techniques used in bridge monitoring. Four case studies are presented. In the first paper, a fully operational Bridge Weigh-In-Motion system is developed and deployed in a steel railway bridge. The gathered data was studied to obtain a characterization of the site specific traffic. In the second paper, the seasonal variability of a ballasted railway bridge is studied and characterized in its natural variability. In the third, the non-linear characteristic of a ballasted railway bridge is studied and described stochastically. In the fourth, a novel damage detection algorithm based in Bridge Weigh-In-Motion data and machine learning algorithms is presented and tested on a numerical experiment. In the fifth, a bridge and traffic monitoring system is implemented in a suspension bridge to study the cause of unexpected wear in the bridge bearings. Some of the major scientific contributions of this work are: 1) the development of a B-WIM for railway traffic capable of estimating the load on individual axles; 2) the characterization of in-situ measured railway traffic in Stockholm, with axle weights and train configuration; 3) the quantification of a hitherto unreported environmental behaviour in ballasted bridges and possible mechanisms for its explanation (this behaviour was shown to be of great importance for monitoring of bridges located in colder climate) 4) the statistical quantification of the nonlinearities of a railway bridge and its yearly variations and 5) the integration of B-WIM data into damage detection techniques. / <p>QC 20140910</p>

[pt] As interações fluido-estrutura são muito comuns na engenharia mecânica e civil porque muitas estruturas, como pontes, plataformas de petróleo, linhas de transmissão ou turbinas eólicas, estão diretamente em contato com um fluido, que pode ser o ar, no caso de vento, ou água, que irá perturbar a estrutura através de ondas. Um papel importante do engenheiro é prevenir a falha da estrutura devido às instabilidades criadas pelas interações fluidoestrutura. Este trabalho apresentará em primeiro lugar todos os conceitos básicos necessários para o estudo de problemas de interação fluido-estrutura. Assim, é realizada uma análise dimensional visando classificar os problemas de fluido-estrutura. A classificação é baseada na velocidade reduzida, e algumas conclusões sobre as conseqüências das interações fluido-estrutura podem ser feitas em termos de estabilidade ou, o que é mais interessante, de instabilidade. De fato, usando modelos simplificados, pode-se mostrar instabilidades estáticas e dinâmicas, induzidas por fluxo, que podem ser críticas para a estrutura. As partes finais do trabalho apresentarão uma estrutura não-linear específica, uma ponte suspensa. Primeiro, a formulação de um modelo simplificado unidimensional é explicada e, em seguida, através de uma discretização por elementos finitos, é realizado um estudo dinâmico. Além disso, algumas conclusões são apresentadas sobre a dinâmica das pontes suspensas. A última parte deste trabalho apresenta um método que foi uma importante fonte de publicação para nós, o método de decomposição regular. / [en] Fluid-structure interactions are very common in mechanical and civil engineering because many structures, as bridges, offshore risers, transmission lines or wind turbines are directly in contact with a fluid, which can be air, which will be source of wind, or water, which will perturb the structure through waves. An important role of the engineer is to prevent structure failure due to instabilities created by the fluid-structure interactions. This work will first present all the basic concepts needed for the study of fluid-structure interaction problems. Thus, a dimensional analysis of those problems is performed and also all the equations governing such cases are presented. Then, thanks to the dimensional analysis made, a classification of problems, namely based on the reduced velocity, can be done and some conclusions concerning the consequences of the fluid-structure interactions can be drawn in terms of stability or, which is more interesting, instability. Indeed, using simplified models one can show static and dynamic flow-induced instabilities that may be critical for the structure. The final parts of the work will present a specific non-linear structure, a suspension bridge. First the formulation of a simplified one-dimensional model is explained and then, through a finite element discretization, a dynamical study is performed. Also, some conclusions are made concerning the dynamic of suspension bridges. The last part of this work presents a method that was an important source of publication for us, the Smooth Decomposition method.