Abstract : Fragility curves are a very useful tool for seismic risk assessment of bridges. A fragility curve describes the probability of a structure being damaged beyond a specific damage state for different levels of ground shaking. Since more than half of all bridges in the province of Quebec (Canada) are in service for more than 30 years and that these bridges were designed at that time without seismic provisions, generating fragility curves for these structures is more than necessary. These curves can be used to estimate damage and economic loss due to an earthquake and prioritize repairs or seismic rehabilitations of bridges. Previous studies have shown that seismic damage experienced by bridges is not only a function of the epicentral distance and the severity of an earthquake but also of the structural characteristics of the bridge and the soil type on which it is built. Current methods for generating fragility curves for bridges do not account for soil conditions. In this work, analytical fragility curves are generated for multi-span continuous concrete girder bridges, which account for 21% of all bridges in Quebec, for the different soil profile types specified in the Canadian highway bridge design code (CAN/CSA-S6-06). These curves take into account the different types of abutment and foundation specific to these bridges. The fragility curves are obtained from time-history nonlinear analyses using 120 synthetic accelerograms generated for eastern Canadian regions, and from a Monte Carlo simulation to combine the fragility curves of the different structural components of a bridge||Résumé : Les courbes de fragilité sont un outil très utile pour l’évaluation du risque sismique des ponts. Une courbe de fragilité représente la probabilité qu'une structure soit endommagée au-delà d'un état d'endommagement donné pour différents niveaux de tremblement de terre. Étant donné que plus de la moitié des ponts dans la province de Québec (Canada) ont plus de 30 années de service et que ces ponts n'ont pas été conçus à l'époque à l'aide de normes sismiques, la génération de courbes de fragilité pour ces structures est plus que nécessaire. Ces courbes peuvent servir à estimer les dommages et les pertes économiques causés par un tremblement de terre et à prioriser les réparations ou les réhabilitations sismiques des ponts. Des études antérieures ont montré que l'endommagement subi par les ponts suite à un tremblement de terre n'est pas seulement fonction de la distance de l'épicentre et de la sévérité du tremblement de terre, mais aussi des caractéristiques structurales du pont et du type de sol sur lequel il est construit. Les méthodes actuelles pour générer les courbes de fragilité des ponts ne tiennent pas compte des conditions du sol. Dans ce travail de recherche, des courbes de fragilité analytiques sont générées pour les ponts à portées multiples à poutres continues en béton armé, soit pour 21% des ponts au Québec, pour les différents types de sol spécifiés dans le Code canadien sur le calcul des ponts routiers (CAN/CSA-S6-06). Ces courbes prennent en compte les différents types de culée et de fondation spécifiques à ces ponts. Les courbes de fragilité sont obtenues à partir d'analyses temporelles non linéaires réalisées à l'aide de 120 accélérogrammes synthétiques généres pour l’est du Canada, et d'une simulation de Monte Carlo pour combiner les courbes de fragilité des différentes composantes du pont.

Made available in DSpace on 2016-06-02T20:09:18Z (GMT). No. of bitstreams: 1 5306.pdf: 6510064 bytes, checksum: b7a3095b2eb1b62ba399cfe3a2684382 (MD5) Previous issue date: 2013-07-11 / Financiadora de Estudos e Projetos / This report investigates the structural behavior, procedures for analysis and design of externally prestressed steel-concrete composite beams. Based upon the requirements outlined in ABNT NRB 8800:2008 for conventional composite beams and in the literature review, a systematic procedure was developed to design of externally prestressed steel-concrete composite beams requested the positive bending moment. Was analyzed the main modes of global collapse, especially the ultimate limit state design (ELU), which may occur in this type of structure. Also, elaborated a parametric study aimed to analyze the influence of variation in the level of prestressing and the eccentricity of tendons, as well as the constructive methodology (pretensioning and posttensioning) adopted for the the prestressing steel profile that makes up the of steel-concrete composite beam. The parametric study showed that in both methods the predominant failure mode occurs in 2nd Stage of construction. In models of composite beams analyzed with application of pretensioned when the tendon is positioned above the bottom flange of the profile steel the failure mode occurred for the combined bending and axial compression .As for the composite beams evaluated with posttensioned, independent of the position of the tendon, the failure mode occurred in function of the bending moment more than the allowable flexural strength. However, it is noted that the level of prestressing can be adequately calculated to ensure that there is no loss of carrying capacity of the structure. It was also observed that regardless of the constructive methodology adopted, higher eccentricities result in higher bearing capacity for the steel beam, as exposed in the literature review. While in Brazil is largely unexplored, there was widespread interest in the international literature on the subject in question and their variances, giving rise to theoretical and experimental. Also been mentioned as potential applications in the design of new structures and the renovation and rehabilitation of existing structures. / O presente trabalho discorre sobre o comportamento estrutural, procedimentos de análise e dimensionamento de vigas mistas de aço e concreto protendidas externamente. Embasado nas prescrições expostas na norma ABNT NRB 8800:2008 para vigas mistas convencionais e na revisão bibliográfica, um procedimento de cálculo foi desenvolvido para o dimensionamento de vigas mistas de aço e concreto protendidas externamente e solicitadas a momento fletor positivo. Foram analisados os principais modos de colapso globais, com destaque nos estados limites de últimos (ELU), que podem ocorrer nesse tipo de estrutura. Além disso, elaborou-se um estudo paramétrico que teve como objetivo analisar a influência da variação do nível de protensão e da excentricidade dos cabos de protensão; bem como da metodologia construtiva (pré-tração e pós-tração) adotada para a protensão do perfil de aço que compõe a viga mista de aço e concreto. O estudo paramétrico demonstrou que em ambas as metodologias o modo de colapso predominante ocorre na 2ª Etapa de construção. Nos modelos de vigas mistas analisados com aplicação de pré-tração quando o cabo está posicionado acima da mesa inferior do perfil de aço o modo de falha ocorreu por flexo-compressão. Já para as vigas mistas avaliadas com pós-tração, independe da posição do cabo, ocorre em função do momento fletor solicitante superar o momento fletor resistente da seção. No entanto, observa-se que o nível de protensão pode ser adequadamente dimensionado de maneira que não provoque a perda da capacidade de suporte da estrutura. Observou-se ainda que independente da metodologia construtiva adotada, maiores excentricidades resultam em maior capacidade resistente para a viga de aço, corroborando os estudos expostos na revisão bibliográfica. Embora no Brasil seja pouco explorado, observou-se um amplo interesse na literatura internacional sobre o tema em questão e suas variâncias, dando origem a pesquisas teóricas e experimentais. Também se aponta como potencialidades de aplicação em projetos de novas estruturas bem como na recuperação e reabilitação de estruturas existentes.

Le dimensionnement basé sur la performance (DBP), dans une approche déterministe, caractérise les objectifs de performance par rapport aux niveaux de performance souhaités. Les objectifs de performance sont alors associés à l'état d'endommagement et au niveau de risque sismique établis. Malgré cette approche rationnelle, son application est encore difficile. De ce fait, des outils fiables pour la capture de l'évolution, de la distribution et de la quantification de l'endommagement sont nécessaires. De plus, tous les phénomènes liés à la non-linéarité (matériaux et déformations) doivent également être pris en considération. Ainsi, cette recherche montre comment la mécanique de l'endommagement pourrait contribuer à résoudre cette problématique avec une adaptation de la théorie du champ de compression modifiée et d'autres théories complémentaires. La formulation proposée adaptée pour des charges monotones, cycliques et de type pushover permet de considérer les effets non linéaires liés au cisaillement couplé avec les mécanismes de flexion et de charge axiale. Cette formulation est spécialement appliquée à l'analyse non linéaire des éléments structuraux en béton soumis aux effets de cisaillement non égligeables. Cette nouvelle approche mise en œuvre dans EfiCoS (programme d'éléments finis basé sur la mécanique de l'endommagement), y compris les critères de modélisation, sont également présentés ici. Des calibrations de cette nouvelle approche en comparant les prédictions avec des données expérimentales ont été réalisées pour les murs de refend en béton armé ainsi que pour des poutres et des piliers de pont où les effets de cisaillement doivent être pris en considération. Cette nouvelle version améliorée du logiciel EFiCoS a démontrée être capable d'évaluer avec précision les paramètres associés à la performance globale tels que les déplacements, la résistance du système, les effets liés à la réponse cyclique et la quantification, l'évolution et la distribution de l'endommagement. Des résultats remarquables ont également été obtenus en référence à la détection appropriée des états limites d'ingénierie tels que la fissuration, les déformations unitaires, l'éclatement de l'enrobage, l'écrasement du noyau, la plastification locale des barres d'armature et la dégradation du système, entre autres. Comme un outil pratique d'application du DBP, des relations entre les indices d'endommagement prédits et les niveaux de performance ont été obtenus et exprimés sous forme de graphiques et de tableaux. Ces graphiques ont été développés en fonction du déplacement relatif et de la ductilité de déplacement. Un tableau particulier a été développé pour relier les états limites d'ingénierie, l'endommagement, le déplacement relatif et les niveaux de performance traditionnels. Les résultats ont démontré une excellente correspondance avec les données expérimentales, faisant de la formulation proposée et de la nouvelle version d'EfiCoS des outils puissants pour l'application de la méthodologie du DBP, dans une approche déterministe. / Abstract : Performance Based Design (PBD) methodology, in a deterministic approach, characterizes the performance objectives in relation to the desired performance levels. Performance objectives are associated with the stated damage condition and the seismic hazard level. Despite this rational approach, its application is still difficult and reliable tools for capturing the evolution, distribution and measuring the damage are indeed required. All phenomena related to nonlinearities (materials and deformations) must also be considered. This research shows how the Damage mechanic could contribute to solving this problematic jointly with an adaptation of the MCFT (Modified Compression Field Theory) formulation and other complementary theories. The proposed formulation, adapted for monotonic, pushover and cyclic loads, allows considering the nonlinear shear-related effects coupled with axial and flexural mechanisms. This formulation is specially addressed to nonlinear analysis of concrete structural elements subjected to non-negligible shear effects. This new approach implemented in EfiCoS (a layered damage mechanic based finite element program), including modeling criteria, is also presented here. Calibrations of this new approach comparing the predictions with experimental data were carried out for concrete shear walls as well as for concrete beams and bridge columns where shear effects have to be considered. This new improved version of software EFiCoS demonstrated to be capable of evaluating accurately the parameters associated with the overall performance, such as displacements, the system strength, the effects related to the cyclic response and the magnitude, evolution and distribution of the damage. Remarkable results were also obtained in reference to the appropriate detection of engineering limit states such as cracking, strains, spalling in cover, crushing, local yielding in bars and system strength degradation, among others. As a very useful application tool for PBD, relationships between the predicted damage indices and the performance levels were obtained and expressed as charts and tables. These charts were derived in terms of the drift and the displacement ductility. A particular table was developed to relate the engineering limit states, the damage, the drift and the traditional performance levels. Results have shown a very good agreement with the experimental data, making the proposed formulation and the new version of EfiCoS a powerful tool for the application of the PBD methodology, in a deterministic approach.

The final thesis is focused on design of valley bridging on I/38 road at the Havlickuv Brod bypass. The thesis contains study of the bridging area. For detailed assessment was chosen, from three variants, a two-beam cross-section girder of 4 spans. Load-bearing structure is designed as cast-in-place, post-tensioned, concreted at fixed falsework without phased construction. The serviceability limit state and the ultimate limit state were assessed. The thesis contains, apart from structural design, drawings and visualizations of the bridge.

Diploma thesis deals with design of a road bridge over Husí potok in Hladké Životice. The supporting structure of the bridge is designed in three variants, one of which is selected variant post-tensioned slabs. To address the internal forces is used computing software Scia Engineer. In the structural analysis of the bridge structure is assessed at the ultimate limit state and serviceability by European standards – Eurocodes. For chosen variant is prepared drawing documentation and visualization.

The diploma thesis deals with the design of a road bridge on the I/57 expressway over the relocation of the cycle path, the Opavice river and the local road, which involves the relocation of the access to the waterworks. The bridge structure is located in the territory of the town of Krnov. A study of the area's bridges is part of the project and three studies have been prepared. Study A was chosen for detailed processing. It is a continuous box girder bridge with three spans. The superstructure is designed as a monolithic, post-tensioned structure. A sliding girder is being investigated for the structure's construction. Scia Engineer 18.1 is used to do the load effects computation. Only the consequences of vertical load effects have been addressed, with no consideration of horizontal load effects. The structure was evaluated using limit states, taking into account the impact of construction on its design.

Owners of dams in the Czech Republic are obliged to ensure the safety management. Part of it is measurement that covers comparing of measured values with limit values (threshold limits). Czech legislation provides principles of safety management e.g. regular observation and monitoring, their periodicity or measured variables. Expectation of reducing the probability of failure, automatic data acquisition system and dam ageing are reasons for adjusting limit values systematically. The aim of this thesis is to specify the method of determination the limit values of displacement for making a vertical survey of embankment dams. The method is demonstrated on the case study of Moravka dam. Sensitivity analysis of hydro-mechanical coupled model of embankment dam is included.

The diploma thesis is focused on design on loadbearing reinforced concrete structure of multi-storey apartment building with shops and offices on the ground floor and underground garage. The thesis consists of the analysis and design of ceiling slabs above underground floor, supporting columns and the beam under the underground floor ceiling slab. Calculation 3D model was created to determine internal forces. All structures are designed according to EC2, ČSN EN 1992-1-1. The thesis includes elaboration of static calculation, shape drawings, drawings of reinforcement of solved structures. The rest of the project part are not analysed.

The subject of this diploma thesis is the design of deep foundation highway bridge on D3 motorway in km 112.574, over Bošilecký stream and evaluation of geomorphological, geological and hydrogeological conditions and perform static calculation bridge foundation

The thesis focuses on design of prestressed concrete footbridge which passes pedestrian and bicycle path over the Elbe river near city of Celakovice in the Czech Republic. Three different bridge options were analyzed and for further development a cable-stayed footbridge was chosen. Its bridge deck is formed of a box girder supported by cables in its vertical axis and all cable stays are anchored into two concrete A-shaped pylons. This structure was analyzed in SCIA Engineer and assessment of serviceability limit states and ultimate limit states according to recent European standards (Eurocodes) was made. Both the global structural behavior and the local structural integrity of box cross-section were assessed as well as construction stages and cross-sections of pylons and cable stays. Assessments were performed in IDEA StatiCa combined with hand calculations. Eventually a dynamic response of structure was analyzed. Natural modes and frequencies were found and forced oscillation response was evaluated. The thesis includes technical drawings, construction process and visualization.