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Serviceability performance of steel-concrete composite beamsLawson, R.M., Lam, Dennis, Aggelopoulos, E.S., Nellinger, S. 22 November 2016 (has links)
Yes / For composite beams with low degrees of shear connection, additional deflections occur due to slip in the shear connectors, which can be significant for beams with low degrees of shear connection. A design formula is presented for the effective stiffness of composite beams taking account of the stiffness of the shear connectors, which is compared to measured deflections of 6 symmetric beams and an 11m span composite beam of asymmetric profile. It is shown that the comparison is good when using a shear connector stiffness of 70 kN/mm for single shear connectors and 100 kN/mm for pairs of shear connectors per deck rib. Results of push tests on a range of deck profiles confirm these initial elastic stiffnesses. To ensure that the slip at the serviceability limit state does not lead to permanent deformations of the beam, it is proposed that the minimum degree of shear connection should not fall below 30% for un-propped beams and 40% for propped beams of symmetric cross-section. / European Commission
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A pre-study of the static behaviour of a single diagonal timber arch bridgeÖhgren, Lovisa, Åström, Malin January 2020 (has links)
The aim of this thesis is to study and gain more insight about the static behaviour of the three hinged single diagonal timber arch bridge in different situations. The bridge was tested for static analyses for both Ultimate Limit State and Serviceability Limit State, to investigate its behaviour and if it is possible to be built at the selected location. Furthermore, the dimensions of the elements are to be determined. Pre-studies on similar bridges have been done and their problems have been taken into account when analysing the behaviour of this bridge. Thereafter, two different designs have been constructed. The finite element software RFEM has been used in this project to be able to analyse the behaviour of the two different models. The in-plane buckling of the arch is the most critical part of the bridge and the bridge should therefore be designed regarding that. Additionally, different alternatives were suggested to reduce the deformation of the deck in the models. Finally, an optimized model is reached which consists of longitudinal beams and has an arch with a wide cross section.
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Estudo das vibrações induzidas por pedestres em passarelas de madeira / Study of pedestrian-induced vibrations on timber footbridgesSegundinho, Pedro Gutemberg de Alcântara 17 May 2010 (has links)
No Brasil, o estudo a respeito das vibrações induzidas por pedestres em passarelas vem sendo realizado a partir do início dos anos 1990, para passarelas de concreto e de aço. No entanto, ainda não há registro de estudos desse tipo e a norma brasileira NBR 7190 (1997) de projeto de estruturas de madeira apresenta somente critérios de dimensionamento para carregamentos estáticos, no caso de passarelas de madeira. Nesse contexto, este trabalho tem como objetivo geral a análise teórica, numérica e experimental de passarelas de madeira simplesmente apoiadas, com vistas a propor recomendações de projeto relacionadas ao conforto humano nessas estruturas. Este estudo foi desenvolvido a partir da análise de diretrizes normativas e critérios sugeridos por diversos autores, da análise teórica de passarelas dimensionadas segundo os critérios da NBR 7190 (1997), de modelos numéricos construídos em elementos finitos e de ensaios experimentais em modelo reduzido. Entre as conclusões alcançadas, destaca-se que a formulação de Euler-Bernoulli é adequada para o cálculo da primeira frequência natural nas direções transversal vertical e transversal horizontal em passarelas de madeira simplesmente apoiadas; entretanto, especial atenção deve ser dada para a avaliação da rigidez à flexão na direção transversal horizontal. Finalmente, sugeriu-se uma proposta para verificação do estado limite de serviço devido às vibrações induzidas por pedestres em passarelas de madeira simplesmente apoiadas, no tocante ao cálculo de frequências e acelerações, a ser inserida na futura revisão da norma brasileira de projeto de estruturas de madeira. / In Brazil, studies about pedestrian-induced vibrations on footbridges have been carried out since the early 1990s, for concrete and steel footbridges. However, there is no record of such studies and the brazilian standard NBR 7190 (1997) for the design of timber structures only presents design requirements for static loads, in the case of timber footbridges. Therefore, this paper aims to general theoretical analysis, numerical and experimental simply-supported beams timber footbridges, with a view to proposing recommendations for projects related to human comfort in these structures. This study was developed from the study of standards guidelines and criteria suggested by several authors, the theoretical analysis of footbridges design according to the criteria of the NBR 7190 (1997), numerical models using finite element and experimental tests on reduced model. Among the conclusions reached, it is emphasized that the formulation of Euler-Bernoulli is suitable for calculating the first natural frequency in vertical and lateral directions simply-supported beams timber footbridges; however, special attention should be given to the evaluation of lateral bending stiffness. Finally, we have suggested a proposal serviceability limit state verification due to pedestrian-induced vibrations on simply-supported beams timber footbridges, concerning the calculation of frequencies and accelerations to be included in a future review of the brazilian standard for the design of timber structures.
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Estudo das vibrações induzidas por pedestres em passarelas de madeira / Study of pedestrian-induced vibrations on timber footbridgesPedro Gutemberg de Alcântara Segundinho 17 May 2010 (has links)
No Brasil, o estudo a respeito das vibrações induzidas por pedestres em passarelas vem sendo realizado a partir do início dos anos 1990, para passarelas de concreto e de aço. No entanto, ainda não há registro de estudos desse tipo e a norma brasileira NBR 7190 (1997) de projeto de estruturas de madeira apresenta somente critérios de dimensionamento para carregamentos estáticos, no caso de passarelas de madeira. Nesse contexto, este trabalho tem como objetivo geral a análise teórica, numérica e experimental de passarelas de madeira simplesmente apoiadas, com vistas a propor recomendações de projeto relacionadas ao conforto humano nessas estruturas. Este estudo foi desenvolvido a partir da análise de diretrizes normativas e critérios sugeridos por diversos autores, da análise teórica de passarelas dimensionadas segundo os critérios da NBR 7190 (1997), de modelos numéricos construídos em elementos finitos e de ensaios experimentais em modelo reduzido. Entre as conclusões alcançadas, destaca-se que a formulação de Euler-Bernoulli é adequada para o cálculo da primeira frequência natural nas direções transversal vertical e transversal horizontal em passarelas de madeira simplesmente apoiadas; entretanto, especial atenção deve ser dada para a avaliação da rigidez à flexão na direção transversal horizontal. Finalmente, sugeriu-se uma proposta para verificação do estado limite de serviço devido às vibrações induzidas por pedestres em passarelas de madeira simplesmente apoiadas, no tocante ao cálculo de frequências e acelerações, a ser inserida na futura revisão da norma brasileira de projeto de estruturas de madeira. / In Brazil, studies about pedestrian-induced vibrations on footbridges have been carried out since the early 1990s, for concrete and steel footbridges. However, there is no record of such studies and the brazilian standard NBR 7190 (1997) for the design of timber structures only presents design requirements for static loads, in the case of timber footbridges. Therefore, this paper aims to general theoretical analysis, numerical and experimental simply-supported beams timber footbridges, with a view to proposing recommendations for projects related to human comfort in these structures. This study was developed from the study of standards guidelines and criteria suggested by several authors, the theoretical analysis of footbridges design according to the criteria of the NBR 7190 (1997), numerical models using finite element and experimental tests on reduced model. Among the conclusions reached, it is emphasized that the formulation of Euler-Bernoulli is suitable for calculating the first natural frequency in vertical and lateral directions simply-supported beams timber footbridges; however, special attention should be given to the evaluation of lateral bending stiffness. Finally, we have suggested a proposal serviceability limit state verification due to pedestrian-induced vibrations on simply-supported beams timber footbridges, concerning the calculation of frequencies and accelerations to be included in a future review of the brazilian standard for the design of timber structures.
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Návrh předpjaté stropní konstrukce / Design of a prestressed slabJuříček, Lukáš January 2018 (has links)
Diploma thesis is focused on the design of prestressed concrete membrane from the lightweight concrete. The concrete membrane is in the interaction with the bearing steel structure, which one is supported. I did only one variant of the solution, which was optimized. The goal of the design was determined the initial state of a membrane and ensure to in the end of design working life was the membrane in the compression state and the cracks couldn’t appear. The structure is modelled in the main (longitudinal) direction as a spatial frame in program ANSYS 17.2. This tool enables to perform analysis of the construction stages. The rheology is calculated manually and supplied to the model as relative strain. The whole structure is checked for ultimate limit state and serviceability limit state according to valid Eurocodes. Transverse direction is modelled by shell elements in program RFEM 5.12. Construction stages and global behaviour of the structure were analysed. The checks have been calculated manually and control in program IDEA StatiCa. The attachments of the thesis are drawings, visualisation and schemes of construction stages.
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Nosná železobetonová konstrukce vícepodlažního objektu / Load-bearing RC structure of the multi-storey buildingPetrovič, Jiří January 2019 (has links)
The Master’s thesis is focused on the analysis and design of selected members of load-bearing structure of an apartment house according to the ultimate limit states (ULS) and seviceability limit states (SLS). The calculation and the analysis was supported by design software SCIA ENGINEER 2017. Structural analysis deals with the design of the reinforced concrete floor slab of 1.PP, beams in 1.PP, selected walls in 1.NP and column in 1.PP and 1.NP. Thework beside this deals with the calculation and design of foundation of the object.
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Železobetonová konstrukce polyfunkčního domu / Reinforced concrete structure of a multifunction buildingPohl, Martin January 2019 (has links)
The diploma thesis deals with structural solution of the reinforced structures of the polyfunctional building. The structure is designed and assessed for for ultimate limit state in accordance with ČSN EN 1992-1-1: Design of concrete structures – Part 1-1: General rules and rules for buildings.
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Lávka pro pěší podporovaná kabely / Cable-supported pedestrian bridgeHlava, Martin January 2015 (has links)
The purpose of the master’s thesis is about a concept of a pedestrian bridge´s bearing construction for pedestrian endorsed wires above a highway R35. The work includes a statical construction calculation of the suspended foot bridge of six spans, which has been chosen from three options. The chosen option is built of a monolithic, pre-stressed concrete board supported by suspenders, which is made by segmental elements above the fast highway. Calculation of a longitudinal direction has been made in an ANSYS application. Assembling status and cross direction of the construction has been modelled at SCIA Engineer. The construction´s recognition has been made manually expect of several towers cross-section, where the judgement has been made at IDEA StatiCa.
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Obchodní galerie / Shopping galleryRichtrová, Pavla January 2015 (has links)
The aim of this theis was to design of load-carrying steel structure of shopping mall in two variations. Geometric proposal and examination of structural element was made for both of variations. Then one variant was selected for detailed elaboration of details and drawings.
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Lávka pro pěší přes řeku Berounku / Footbridge over the Berounka riverPejčoch, Karel January 2017 (has links)
THE OBJECT OF THE MASTER THESIS IS TO DESIGN OF SUPPORTING STRUCTURE OF PEDESTRIAN BRIDGE SITUATED OVER THE RIVER OF BEROUNKA. THE THESIS CONTAINS STATIC ANALYSIS OF THE CABLE-STAYED BRIDGE WITH TWO FIELDS, WHICH WAS CALCULATED IN THREE VERSIONS .THE CHOSEN VERSION OF THE BRIDGE CONSIST OF MONOLITIC AND PRECAST CONCRETE BRIDGE DECK, WHICH IS CONSTRAINED USING PRESTRESSED CABELS AND SUPPORTED BY HANGINGS.THE CALCULATIONS OF THE LONGITUDINAL WAS PERFORMED BY COMPUTATIONAL SOFTWARE OF SCIA ENGINEERING 15.1
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