Дисертації з теми "Axial bending"
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Agarwal, Rohit. "Tube bending with axial pull and internal pressure." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/442.
Повний текст джерелаRahman, Muhammad Motiur. "Geopolymer concrete columns subjected to axial load and biaxial bending." Thesis, Curtin University, 2013. http://hdl.handle.net/20.500.11937/1410.
Повний текст джерелаChenaghlou, Mohammad Reza. "Semi-rigidity of connections in space structures." Thesis, University of Surrey, 1997. http://epubs.surrey.ac.uk/800044/.
Повний текст джерелаNanou, Katerina. "Design of open cold rolled sections under axial force and bending moment." Thesis, Imperial College London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324988.
Повний текст джерелаCastori, Giulia. "Interaction between axial force, shear and bending moment in reinforced concrete elements." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8519/.
Повний текст джерелаLIMA, LUCIANO RODRIGUES ORNELAS DE. "BEHAVIOUR OF STRUCTURAL STEEL ENDPLATE JOINTS SUBJECTED TO BENDING MOMENT AND AXIAL FORCE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4165@1.
Повний текст джерелаTradicionalmente, o projeto de pórticos em estruturas de aço assume que as ligações viga-coluna são rígidas ou flexíveis. As ligações rígidas, onde não ocorre nenhuma rotação entre os membros conectados, transferem não só momento fletor, mas também força cortante e força normal. Por outro lado, as ligações flexíveis são caracterizadas pela liberdade de rotação entre os membros conectados impedindo a transmissão de momento fletor. Desconsiderando- se estes fatos, sabe-se que a grande maioria das ligações não possuem este comportamento idealizado. De fato, a maioria das ligações transfere algum momento fletor com um nível de rotação associado. Estas ligações são chamadas semi-rígidas e seu dimensionamento deve ser executado de acordo com este comportamento estrutural real. Porém, algumas ligações viga-coluna estão sujeitas a uma combinação de momento fletor e esforço axial. O nível de esforço axial pode ser significativo, principalmente em ligações de pórticos metálicos com vigas inclinadas, em pórticos não-contraventados ou em pórticos com pavimentos incompletos. As normas atuais de dimensionamento de ligações estruturais em aço não consideram a presença de esforço axial (tração e/ou compressão) nas ligações. Uma limitação empírica de 5 por cento da resistência plástica da viga é a única condição imposta no Eurocode 3. O objetivo deste trabalho é descrever alguns resultados experimentais e numéricos para estender a filosofia do método das componentes para ligações com ações combinadas de momento fletor e esforço axial. Para se cumprir este objetivo, quinze ensaios foram realizados e um modelo mecânico é apresentado para ser usado na avaliação das propriedades da ligação: resistência à flexão, rigidez inicial e capacidade de rotação.
Traditionally, the steel portal frame design assumes that beam-to-column joints are rigid or pinned. Rigid joints, where no relative rotations occur between the connected members, transfer not only substantial bending moments, but also shear and axial forces. On the other extreme, pinned joints, are characterised by almost free rotation movement between the connected elements that prevents the transmission of bending moments. Despite these facts, it is largely recognised that the great majority of joints does not exhibit such idealised behaviour. In fact, many joints transfer some bending moments associated with rotations. These joints are called semi-rigid, and their design should be performed according to their real structural behaviour. However, some steel beam-to-column joints are often subjected to a combination of bending and axial forces. The level of axial forces in the joint may be significant, typical of pitched-roof portal frames, sway frames or frames with incomplete floors. Current standard for steel joints do not take into account the presence of axial forces (tension and/or compression) in the joints. A single empirical limitation of 5 percent of the beam s plastic axial capacity is the only enforced provision in Annex J of Eurocode 3. The objective of the present work is to describe some experimental and numerical results to extend the philosophy of the component method to deal with the combined action of bending and axial forces. To fulfil this objective a set of sixteen specimens were performed and a mechanical model was developed to be used in the evaluation of the joint properties: bending moment resistance, initial stiffness and rotation capacity.
Scott-Emuakpor, Onome Ejaro. "Development of a novel energy-based method for multi-axial fatigue strength assessment." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1196280356.
Повний текст джерелаDoruk, Koray. "Fiber Reinforced Polymer Confined Rc Circular Columns Subjected To Axial Load And Bending Moment." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607474/index.pdf.
Повний текст джерелаPing, Hsin-Chih. "Coupled axial and bending vibrations of a uniform beam-column with an oblique crack /." Thesis, Connect to this title online; UW restricted, 1997. http://hdl.handle.net/1773/7076.
Повний текст джерелаJadid, Mansour Nasser. "The application of neural network techniques to the analysis of reinforced concrete beam-column joints subjected to axial load and bi-axial bending." Thesis, University of Edinburgh, 1994. http://hdl.handle.net/1842/14160.
Повний текст джерелаVan, Toen Carolyn Yvonne. "Biomechanics of cervical spine and spinal cord injury under combined axial compression and lateral bending loading." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45728.
Повний текст джерелаENCISO, ROXANA OLARTE. "BEHAVIOR OF SLENDER HIGH STRENGTH CONCRETE COLUMNS SUBJECTED TO AXIAL LOAD AND BENDING ABOUT ONE AXIS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2010. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=16425@1.
Повний текст джерелаEste trabalho apresenta um estudo experimental do comportamento de pilares esbeltos de alta resistência submetidos à flexão composta reta. Foram ensaiados oito pilares divididos em duas séries, sendo uma série com concreto de 40 MPa e a outra com concreto de 80 MPa aos vinte e oito dias. Todos os pilares tinham seção transversal de 15x25 cm e altura de 300 cm. Em cada série, a variável foi a taxa de armadura longitudinal que assumiu quatro valores diferentes. O objetivo foi verificar os valores da excentricidade de segunda ordem que devem ser considerados no dimensionamento de pilares esbeltos de concreto de alta resistência. Os resultados dos ensaios foram comparados com os resultados teóricos obtidos pelos modelos da curvatura aproximada e da rigidez aproximada que constam na NBR6118:2003. Essa comparação mostrou uma boa concordância entre os resultados experimentais e teóricos.
This work presents an experimental study of the behavior of slender high strength concrete columns under uniaxial eccentric compression loads. Eight columns were tested, divided into two series, one series with concrete of 40 MPa and the other with concrete of 80 MPa at twenty eight days. All columns had a cross-section of 15x25 cm and height of 300 cm. In each series, the variable was the longitudinal reinforcement ratio which assumed four different values. The objective was to verify the values of the eccentricity of second order that should be taken into account in the design of slender high strength concrete columns. The experimental results were compared with theoretical results obtained by the models of the approximated curvature and approximated stiffnes methods prescribed in the NBR6118:2003 code. This comparison showed a good agreement between the experimental and theoretical results.
Lau, J. C. K. "The strength of masonry walls and columns of geometric cross section subjected to axial load and bending." Thesis, University of Manchester, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.705159.
Повний текст джерелаVoinier, Steven. "Passive Stiffness Characteristics of the Scoliotic Lumbar Torso in Trunk Flexion, Extension, Lateral bending, and Axial Rotation." Thesis, Virginia Tech, 2015. http://hdl.handle.net/10919/52241.
Повний текст джерелаMaster of Science
Walters, Martin. "The effects of wall inertia and axial bending on instabilities in flow through an elastic-walled tube." Thesis, University of East Anglia, 2016. https://ueaeprints.uea.ac.uk/58536/.
Повний текст джерелаBairán, García Jesús Miguel. "A non-linear coupled model for the analysis of reinforced concrete sections under bending, shear, torsion and axial forces." Doctoral thesis, Universitat Politècnica de Catalunya, 2005. http://hdl.handle.net/10803/6177.
Повний текст джерелаEl objetivo principal de esta tesis es generalizar el análisis de secciones de hormigón armado mediante fibras, de forma que se pueda reproducir la res-puesta no-lineal acoplada frente a esfuerzos normales y tangenciales bajo solicitaciones tridimensionales generales. De igual forma, se pretende obtener, para los esfuerzos cortantes y torsión, la misma capacidad de representación de geometrías y combinación de materiales que ofrecen los modelos de fibras para esfuerzos de flexo-compresión.
La primera problemática estriba en representar adecuadamente la cinemática de la sección transversal. Con la excepción de las deformaciones normales contenidas en el plano de la sección, no existe una teoría cinemática que a priori pueda dar la distribución del resto de deformaciones o tensiones en la sección, sin dejar de satisfacer las condiciones de equilibrio interno o continuidad entre las fibras que componen la misma.
Por otra parte, para materiales anisótropos, como el hormigón fisurado, en general todos los esfuerzos internos pueden estar acoplados. Además, es preciso considerar la distorsión de la sección transversal para satisfacer el equilibrio entre fibras.
El problema se aborda de forma general, considerando una sección de forma y materiales cualesquiera. Se parte del problema diferencial de equilibrio de un sólido con el que se ha podido deducir un sistema de equilibrio entre fibras (equilibrio a nivel sección). Se puede demostrar que éste es complementario al problema estándar de vigas. El sistema complementario permite recuperar información tridimensional que normalmente se pierde al resolver un problema de vigas.
Posteriormente, se propone una solución interna del problema complementario, en la que el alabeo y la distorsión de la sección quedan expresados como una función de las deformaciones generalizadas de una viga: deformaciones axil y cortantes, curvaturas de flexión y torsión. No son necesarios grados de libertad adicionales a nivel estructura ni hipótesis a-priori sobre la forma de los campos de deformación o tensión interna.
A partir de la formulación teórica, se desarrolla un modelo de elementos finitos plano de la sección transversal. El modelo está preparado para servir como respuesta constitutiva de cualquier tipo de elemento viga en sus puntos de integración. %Se evita así la necesidad de realizar un modelo de elementos sólidos de toda la barra para estudiar la respuesta frente a una combinación general de esfuerzos normales y tangenciales.
Se implementan una serie de modelos constitutivos para distintos materiales. En particular, se implementa un modelo constitutivo triaxial para hormigón fisurado, considerando la anisotropía inducida por la fisuración e incluyendo la superficie de rotura según un criterio multiaxial.
La formulación seccional es validada mediante varios casos de estudio teóricos y experimentales. La respuesta no-lineal acoplada bajo diversas combinaciones de esfuerzos normales y tangenciales es reproducida con precisión, lo cual queda patente tanto en las curvas esfuerzo-deformación obtenidas como en las matrices de rigidez seccionales.
Finalmente, se recopilan las conclusiones derivadas de la presente investigación y se
ofren recomendaciones para futuros trabajos.
Most RC structures are subjected to combined normal and tangential forces, such as bending, axial load, shear and torsion. Concrete cracking, steel yielding and other material nonlinearities produce an anisotropic sectional response that results in a coupling between the effects of normal and shear forces, i.e. normal force or bending moments may produce shear strains and vice versa. Although this interaction is sometimes taken into account, in a simplified manner, in the design of RC structures, a deep analysis of the coupling effects of RC sections using fiber models has not yet been made for arbitrary shape sections under general 3D loading.
The main objective of this thesis is to generalize the fiber-like sectional analysis of reinforced concrete elements, to make it capable of considering the coupled non-linear response under tangential and normal internal forces, from a general 3D loading.
Similarly, it is desired to obtain, for torque and shear forces, the same capacity and versatility in reproducing complex geometry and materials combination that fiber-like sectional representations offers for bending and stretching.
The first problematic lies in finding a proper representation of the section's kinematics under such general loading. Except for in-plane normal strains, there is no single kinematical theory capable of a-priori representing the correct distribution of the others strains or stresses satisfying, at the same time, inter-fiber equilibrium and continuity. On the other hand, for rather anisotropic materials, such as cracked concrete, all internal forces are, in general, coupled. It is also required that distortion is allowed for the section's kinematics in order to guarantee satisfaction of internal equilibrium.
The problem is dealt in a general form considering arbitrary shaped sections and any material behaviour. Starting from the differential equilibrium of a solid, an inter-fiber equilibrium system (equilibrium at the sectional level) was deduced. This system, which is complementary to the standard equilibrium problem of a beam-column, allows to recuperate information of the three-dimensional problem that is generally lost when solving a beam problem.
Further, a solution of the equilibrium at the sectional level is proposed in which the section's warping and distortion are posed as a function of the generalized beam-column strains (axial and shear strains, bending and torsion curvatures). No additional degrees of freedom are required at the structural level nor a-priori hypotheses on the distribution of the internal strains or stresses.
After the theoretical formulation, a planar finite element model for cross-sectional analysis is developed. The model can be used as a constitutive law for general beam column elements at their integration points.
A series of constitutive models have been implemented for several materials. In particular, a triaxial constitutive model for cracked concrete is implemented considering crackinduced anisotropy and a multiaxial failure criterion.
The sectional formulation is validated by means of various theoretical and experimental case studies. Non-linear coupled response under normal and tangential internal forces is reproduced with accuracy, as can be seen both in the predicted internal force-strain curves and in the sectional stiffness matrixes.
Finally, the conclusions drawn from the current research are summarized and
recomendations for future works are given.
Engström, Anders, and Toma Sumbasacu. "The length effect on Norway spruce boards : An investigation on indicating properties based on axial dynamic and edgewise bending MOEs." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-49099.
Повний текст джерелаShope, Ronald L. "Response of Wide Flange Steel Columns Subjected to Constant Axial Load and Lateral Blast Load." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/29521.
Повний текст джерелаPh. D.
Schmitt, Bernardo. "Ensaio biomecânico para determinação do diâmetro de barra conectora de polimetilmetacrilato em fixador esquelético externo tipo Ia: no úmero de suínos." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/10211.
Повний текст джерелаWhile seemingly inert appearance, bones are highly dynamic structures, which promote formation, resorption, repair and maintenance of homeostasis. Fractures in bones occur when the load applied to a specific bone region exceeds its resilience. The use of external skeletal fixator (ESF) is a method of fairly common internal stabilization, in which connector bars polymethylmethacrylate (PMMA) are used without criterion in diameter. In these cases, it can break if it gets too thin or too heavy and uncomfortable when bulky. The aim of this study was to test biomechanical through axial compression and bending, considering different connector bar diameter PMMA correlated to bone diameter for use to type Ia ESF. For this, it was collected 24 swine humerus to make measurements of length, diameter, circumference and testing biomechanical. After the bars confected with 1.5 times the average diameter of the bone (group I), the same diameter bone (group II) and 0.5 times the diameter of the bone (group III). The results obtained, it was observed that the connector bars in group II were more resistant than the bones in the compression test. In the bending test, the bones resisted flexion strength when compared to group III. The group II was 4.3 times more resistant than Group III in the same mechanical test. The results allow a direction for making bars PMMA considering bone diameter as a reference.
Apesar do seu aspeto aparentemente inerte, os ossos são estruturas altamente dinâmicas, envolvidas em constante formação, reabsorção, reparação e manutenção da homeostasia. As fraturas ocorrem quando a carga aplicada sobre determinada região do tecido ósseo supera sua capacidade de resistência. A utilização de fixadores esqueléticos externos (FEE) é método de estabilização interna bastante frequente, no qual podem ser utilizadas barras conectoras de polimetilmetacrilato (PMMA) sem preocupação com o diâmetro. Tais barras podem quebrar se ficarem muito delgadas ou tornarem-se desconfortáveis quando volumosas e pesadas. O objetivo deste trabalho foi testar, por meio de ensaio biomecânico de compressão axial e flexão, qual é o diâmetro mais adequado para a barra conectora de PMMA, correlacionado as dimensões da barra com o diâmetro ósseo para FEE tipo Ia. Para tanto, coletaram-se 24 úmeros suínos para a realização de medidas de comprimento, diâmetro, circunferência e os ensaios biomecânicos. Após, confeccionaram-se barras de 1,5 vezes a média do diâmetro ósseo (grupo I), do mesmo diâmetro (grupo II) e 0,5 vez o diâmetro ósseo (grupo III). Com os resultados obtidos ao comparar os valores dos ossos com os dos grupos II e III, verificou-se que as barras conectoras do grupo II mostraram-se mais resistente do que o tecido ósseo no ensaio de compressão. No ensaio de flexão, o osso foi mais resistente à força de flexão quando comparados ao grupo III. O grupo II foi 4,3 vezes mais resistente do que o grupo III nesse mesmo ensaio. O grupo I apresentou secagem incompleta, onde seu comportamento não foi similar com o restante dos grupos, por isso, não participou da estatística do trabalho. Os resultados permitem um direcionamento para confecção de barras de PMMA do mesmo diâmetro ósseo, sendo suficiente para sustentar sem quebrar um FEE tipo Ia.
Borges, Ana Cláudia Leão. "Análise de pilares esbeltos de concreto armado solicitados a flexo-compressão oblíqua." Universidade de São Paulo, 1999. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-06122017-144257/.
Повний текст джерелаAs a consequence of the actual technological development of the materials steel and concrete, many researches have come up with proposal of better use of these two materials capacity, demanding a bigger knowledge about the behaviour of the elements, included your vulnerability to ultimate limit states. Being the instability a possible ultimate limit state of reinforced concrete columns equilibrium configuration, this study has been fundamental to make possible to propose safe and economically reasonable structural solutions. This work presents the analysis of some aspects that interfere in the study of slender reinforced concrete columns stability, through an approach involving theoretical and practical aspects derived from numerical solutions. The scheme is based in the General and Equilibrium Methods with the Exact Process and Model Column Method, through a software (SISTEMA FLEXOR) developed by CADAMURO Jr. (1997). The objective is to testify the practicability of these methods, to propose solutions and to render wider and more practical the use of slender reinforced concrete columns, stimulating the adoption of projects bolders without underutilisation of the materials.
Williams, Zachary. "Krouse Fatigue for Metals with Elevated Mean Stress." Ohio University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1597075964521893.
Повний текст джерелаThilakarathna, Herath Mudiyanselage Indika. "Vulnerability assessment of reinforced concrete columns subjected to vehicular impacts." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/43693/1/Herath_Thilakarathna_Thesis.pdf.
Повний текст джерелаMa, Jiayao. "Thin-walled tubes with pre-folded origami patterns as energy absorption devices." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:7502b18d-674d-4eff-bbc4-e649aa4d7f42.
Повний текст джерелаJämting, Åsa. "Mechanical properties of thin sol-gel films." Thesis, Queensland University of Technology, 1999. https://eprints.qut.edu.au/36085/6/A%CC%8Asa%20J%C3%A4mting_Digitised%20Thesis.pdf.
Повний текст джерелаNunes, Pedro Carlos da Lomba. "Análise Paramétrica de Ligações com Placa de Extremidade em Estruturas de Aço Submetidas a Momento Fletor e Força Axial." Universidade do Estado do Rio de Janeiro, 2006. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=424.
Повний текст джерелаUsualmente, o projeto de pórticos em estruturas de aço assume que as ligações viga-coluna são rígidas ou flexíveis. As ligações rígidas, onde não ocorre nenhuma rotação entre os membros conectados, transferem não só momento fletor, mas também força cortante e força normal. Por outro lado, as ligações flexíveis são caracterizadas pela liberdade de rotação entre os membros conectados impedindo a transmissão de momento fletor. Sabe-se que a grande maioria das ligações não possuem este comportamento idealizado. Na realidade, a maioria das ligações transfere algum momento fletor com um nível de rotação associado. Estas ligações são denominadas semi-rígidas e seu dimensionamento deve ser executado de acordo com este comportamento estrutural. Contudo, algumas ligações viga-coluna estão sujeitas a uma combinação de momento fletor (M) e força axial (N). O nível de esforço normal pode ser significativo, principalmente em ligações de pórticos metálicos com vigas inclinadas, em pórticos não- contraventados ou em pórticos com pavimentos incompletos. As normas atuais de dimensionamento de ligações estruturais em aço não consideram a presença de esforço normal (tração e/ou compressão) nas ligações. Uma limitação empírica de 5% da resistência plástica da viga é a única condição imposta no Eurocode 3. O objetivo deste trabalho é realizar uma análise paramétrica de dois tipos de ligações aparafusadas para se avaliar a influência de combinações M/N no comportamento global destas ligações. Para se cumprir este objetivo, os resultados experimentais de quinze ensaios realizados por Lima [1] são comparados com os resultados obtidos através de um modelo analítico proposto por Cerfontaine [2], [3].
Traditionally, the steel portal frame design assumes that beam-to-column joints are rigidor pinned. Rigid joints, where no relative rotations occur between the connected members, transfer not only substantial bending moments, but also shear and axial forces. On the other extreme, pinned joints, are characterised by almost free rotation movement between the connected elements that prevents the transmission of bending moments. Despite these facts, it is largely recognised that the great majority of joints does not exhibit such idealised behaviour. In fact, many joints transfer some bending moments with associated rotations. These joints are called semi-rigid, and their design should be performed according to their real structural behaviour. However, some steel beam-to-column joints are often subjected to a combination of bending (M) and axial forces (N). The level of axial forces in the joint may be significant, typical of pitched-roof portal frames, sway frames or frames with incomplete floors. Current standard for steel joints do not take into account the presence of axial forces (tension and/or compression) in the joints. A single empirical limitation of 5% of the beams plastic axial capacity is the only enforced provision in Eurocode 3. The objective of the present work is to perform a parametrical analysis of two bolted joints types in order to evaluate the influence of M/N combinations in the joints global response. To fulfil this objective, the experimental results obtained by Lima [1] are compared to the analytical results using the Cerfontaine analytical model [2], [3].
Mercier, Charlotte. "Développement d’un modèle de stabilité des barres à section tubulaire comprimées fléchies sensibles aux effets du second ordre." Thesis, Université de Lorraine, 2019. http://www.theses.fr/2019LORR0113/document.
Повний текст джерелаThis thesis is part of an effort to improve knowledge of the instabilities of beam-columns sensitive to second-order effects. The works deal with the means to take into account the initial imperfections in the structural analysis and to adapt the current verification criteria for tubular section structures, such as scaffold structures. The existing formulations, proposed in the literature and calculation codes, are often based on hypotheses, and thus lead to inconsistencies between, on the one hand, the verification criteria in section, and on the other hand, the verification criteria in instability. The developed approach takes into account the interaction between section resistance and instability phenomena, and includes the influence of initial imperfections (initial defect of aplomb, lack of straightness, residual stresses). As far as possible, these effects will be decoupled. As such, a method has been developed to allow the definition of initial imperfections of a structure, to be as accurate as possible. This method, based on the definition of a single imperfection, identical in appearance to the shape of the predominant critical buckling mode, is a precise, fully defined method to take into account the geometric characteristics, intrinsic mechanical characteristics, limits and the form of loading, in the definition of the initial imperfections of a structure. A test campaign was carried out in collaboration with the French Syndicate of Scaffolding, Formwork and Shoring (SFECE), aiming to analyze the experimental behavior of buckling of cold-formed tubular sections. Nine buckling tests on scaffold ladders, from various European suppliers, have been carried out. A statistical study of the experimental results has made it possible to highlight that the imperfection factor currently defined for the cold-formed tubular sections is far too penalizing for the sections used in the field of scaffolds. In order to respond to the problem, new instability criteria have also been established using a similar approach to that of Ayrton-Perry. These new criteria make it possible to free ourselves from the modeling of initial imperfections while offering a safe and accurate estimate of the stress factor of a structure. A comparative study was conducted in order to ensure the safety of the proposed formulations as regards the section verification criteria of the NF EN 1993-1-1 current standard
Silva, Leonardo Martins e. "Programa computacional para análise e verificação de seções de concreto armado e protendido com flexão oblíqua composta." Universidade Federal de São Carlos, 2015. https://repositorio.ufscar.br/handle/ufscar/4707.
Повний текст джерелаFinanciadora de Estudos e Projetos
In this paper, a free analysis program is presented for the verification of ultimate and serviceability limit states of reinforced or prestressed concrete sections with polygonal shape submitted to axial forces and biaxial bending. In addition, the program also calculates the bending-axial force-curvature relation (M, N, 1 / r) of the sections, which can be used in further analysis, for example, the general method for calculating pillars. For this is used the object-oriented programming, so that this work can be resumed and amended, providing technical material for future work in the same line, therefore provides that the calculation routines along with the program. The programming lines and routines includes explanations of its operation to encourage its further use as part of other programs. The data entry is presented as a form and the program enables the exchange of data, both input and output via text type files. The criteria adopted follows the brazilian standard ABNT NBR 6118: 2014, which compared to the previous version features suggestions for concrete with superior characteristic strength higher than 50 MPa. The structure of the routines is presented so that criteria of other standards, or updates of the same Brazilian standard referenced, can be easily implemented. Some validation examples for the program are presented in different situations and finally commented and listed some other extensions which can be made.
No presente trabalho, apresenta-se um programa livre e gratuito de análises e verificações de estados-limite último e de serviço de seções de concreto armado e protendido com forma poligonal submetidas à flexão composta oblíqua. Além disso, o programa calcula também a relação momento-normal-curvatura (M, N, 1/r) das seções, que pode ser usada em outras análises, como por exemplo, o método geral para o cálculo de pilares. Para isso se usa a programação orientada ao objeto, a fim de que o presente trabalho possa ser retomado e alterado, dando subsídio técnico para trabalhos futuros da mesma linha, por esse motivo fornece-se as rotinas de cálculo juntamente ao programa. As linhas e rotinas de cálculo constam com explicações de seu funcionamento para incentivar seu uso posterior como parte de outros programas. A entrada dos dados é feita de forma de formulário e o programa permite a troca de dados, tanto de entrada como de saída através de arquivos do tipo texto. Os critérios adotados seguem a norma brasileira ABNT NBR 6118:2014, que em relação à versão anterior apresenta sugestões para concretos com resistência superior a 50 MPa. A estrutura das rotinas é apresentada de maneira que critérios de outras normas, ou ainda atualizações da mesma norma brasileira referenciada, possam ser facilmente implementadas. Apresenta-se vários exemplos de validação do programa em diversas situações e finalmente comentadas e listadas as ampliações que podem ser feitas.
Malakoski, Joice. "Pilares esbeltos de concreto armado com seção variável." Universidade de São Paulo, 1998. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-22022018-152222/.
Повний текст джерелаThe recommendations of Brazilian Code NBR-6118/1978 and Comité Euro-Internacional du Béton Model Code CEB-1990 are described, for stability verification of concrete slender columns with variable cross sections, subjected to axial load and bending moment, using the exact method. To obtain the second order bending moments, the Engesser-Vianello method and the numeric integration of the cross section curvatures along the longitudinal axial of column method are described. To obtain of bending moment supported by the cross sections due to curvature resultant of the column flexure under axialload, expressions for rectangular and circular (full and hollow) cross sections are developed, using stress-strain relations for materials proposed by model codes above mentioned. It\'s also presented a software written in PASCAL language for microcomputer and destined to column stability verification, with option to adopt the NBR-6118/1978 or CEB-1990 model code recommendations. Effects due to vibrations were nor included. Methods to take in account creep effects were described.
Miotto, José Luiz. "Avaliação dos critérios de dimensionamento para peças comprimidas e flexocomprimidas de madeira." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18134/tde-03052005-150420/.
Повний текст джерелаThe recent revision of NBR 7190/97 culminated in undeniable progresses in the project of the timber structures. The accidental eccentricities, amplification of the eccentricities and the creep effects happen differently in calculation of the short members, the middling slenders or the slenders ones, establishing discontinuities in the diagrams of the design forces in function of slenderness of the members in compression and in combined bending and axial compression. Being associated to other particularities, as the complexity of some of its equations, that model has been often criticized. In this work, the proposed criteria for the verification of the stability of sawed timber members in compression and in combined bending and axial compression are appraised for the following normative documents: german, australian, canadian, european and north americans. Those recommendations are confronted with the brazilian code ones, comparing the objectivity of the methods and the gained results. The proposition of AF&PA/ASCE 16-95/96 for the compressed members design demonstrates great practicality and continuity in the diagrams of Nd x 'lâmbda', avoiding the critics that are connected to the criteria of the brazilian code. On the other hand, the prescriptions of that same code for the members in combined bending and axial compression based in convincing theoretical arguments avoid the deficiencies verified in the proposal of the brazilian code, agreeing with the purposes for suggestion in a necessary normative reformation
Stehno, Pavel. "Statické řešení novostavby administrativní budovy." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226958.
Повний текст джерелаЛазарєв, Іван Вікторович, Иван Викторович Лазарев та Ivan V. Lazariev. "Розробка та вдосконалення методів розрахунку міцності елементів конструкції силових трансформаторів". Thesis, Запорізький національний технічний університет, 2016. http://eir.zntu.edu.ua/handle/123456789/887.
Повний текст джерелаUK: Створено узагальнені методи визначення критичних напружень радіальної стійкості та розрахунку на міцність при дії радіальних і осьових сил гнучкого кругового кільця круглого та прямокутного з заокругленнями кутів перерізу, яке моделює провідники обмоток трансформаторів. Визначено осьові зусилля в деформівних елементах механічної системи, утвореної двома простими осциляторами з розташованими на одній осі безінерційними пружинами і твердими тілами, звязаними паралельними стержнями, на які діють відмінні у часі зосереджені аперіодичні осьові сили, що виникають при коротких замиканнях в обмотках різних фаз трансформатора, розміщених на одному стрижні магнітної системи. Розроблено методи визначення осьових зусиль в деформівних компонентах складної механічної системи, яку утворіють обмотки та конструкція їх пресування, при дії сил, що виникають у процесі виготовлення, транспортування, та експлуатації трансформаторів. EN: Transformer winding conductors were simulated by a flexible circular ring with round and rectangular (filleted and non-filleted) cross-section. For such a ring there were created generalised methods for determining critical stresses of radial stability and for strength analysis under the action of radial an axial forces. There were determined axial internal forces in deformable elements of the mechanical system comprising two simple oscillators with inertialess springs and rigid bodies located on the same axis and connected by parallel rods with the latter being loaded by concentrated aperiodic axial forces that change in time by distinct time functions and originate in windings of different transformer phases installed on the same magnetic system leg. There were developed methods for determining axial internal forces in deformable components of a complex mechanical system comprising windings and their clamping structure under the action of forces occurring in the process of transformer manufacture, shipment and in service. RU: Разработаны обобщенные методы определения критических напряжений радиальной устойчивости и расчета прочности при действии радиальных и осевых сил гибкого кругового кольца круглого и прямоугольного с закруглениями углов сечения, которое моделирует проводники обмоток трансформаторов. Определены осевые усилия в деформируемых элементах механической системы, образованной двумя простыми осцилляторами с расположенными на одной оси безынерционными пружинами и твердыми телами, связанными параллельными стержнями, на которые действуют сосредоточенные апериодические осевые силы, которые изменяются во времени по различающимся функциям, и возникают в обмотках разных фаз трансформатора, расположенных на одном стержне магнитной системы. Разработаны методы определения осевых усилий в деформируемых компонентах сложной механической системы, которую образуют обмотки и конструкция для их прессовки, при действии сил, которые возникают в процессе изготовления, транспортирования и эксплуатации трансформаторов.
CHAN, FU-CHIEH, and 詹富傑. "Seismic behavior of steel reinforced concrete columns subjected to axial load and bi-axial bending." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/24214364015380944232.
Повний текст джерела國立中央大學
土木工程研究所
92
ABSTRACT This study investigated the seismic performance of 24 composite columns composed of H-steel and reinforced concrete. Major parameters studied included the sectional strength ratios and the magnitudes of biaxial bending. It was found from test results that member performance was governed by the strength of reinforced concrete when they were loaded in the section’s weak axis. It was also observed that the performance of member with weak axis bending decreased when the section’s steel strength increased. Test results suggested that the strength ratio between the section’s strong and weak directions be adequately adjusted so that high member performance could be achieved. It is proposed in this study that the ratio be set to 2.2 and 2.5.
陳璽字. "Concrete infilled steel columns subjected to axial load and bending moment." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/79171040185599712906.
Повний текст джерелаLin, Yie-Ming, and 林益民. "Behavior of Reinforced Concrete Columns under Combined Biaxial Bending and Axial Force." Thesis, 1995. http://ndltd.ncl.edu.tw/handle/39690352268326788806.
Повний текст джерелаCheng, Tzu-Chung, and 鄭子仲. "Simultaneous Measurement of Bending Curvature and Axial Stress Using Fiber Bragg Grating Sensors." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/95929429443805820037.
Повний текст джерела逢甲大學
電機工程所
97
In this thesis, simultaneous measurement of bending curvature and axial stress using fiber Bragg grating sensors is presented. The side-polishing technique was used to produce FBG sensors with different polishing lengths and thicknesses. The experimental configurations were used the cantilever beam for measuring the bending curvature range of 0 - 6 m-1 and simply supported beam for measuring curvature range of 31 - 71 m-1. The length of fiber Bragg gratings was 20 mm and the polished residual thickness was from 55.95 to 93.94 �慆. The curvature sensitivity of 0.739 nm/m-1 was obtained by using D-shaped FBG sensor with 50 mm polishing length and a cantilever beam configuration. Finally, the sensing sensitivities of both curvature and axial stress measurements have been improved and demonstrated by changing the mounted method. The bending curvature sensitivity was 1.341 nm/m-1 for the curvature range from 0 to 6 m-1, and the stress sensitivity was 27.90 nm/GPa for the measuring range from 0 to 0.208 GPa.
Weilung, Sun, and 孫維隆. "Experimental Behavior of Stiffened Concrete Filled Tube under Combined Axial and Bending Loads." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/80210011147062856303.
Повний текст джерелаLin, Chih-chong, and 林志聰. "Lateral-Torsional Buckling Analysis of Elastic Beam under Axial Force and Bending Moment." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/32223107805407364581.
Повний текст джерела國立交通大學
機械工程系
89
In this study, a consistent co-rotational formulation of second order beam theory is employed for the nonlinear lateral-torsional buckling analysis of three-dimensional elastic Euler beam under axial force and bending moment. The beam structure is divided into several segments, called beam element for convenience. A set of element coordinate system is constructed at the current configuration of the deformed beam element. The deformations, equilibrium equations, and constitutive equations of the beam element are defined in the element coordinates. The principle of virtual work and the consistent second order linearization of the fully geometrically nonlinear beam theory are used to derive the equilibrium equations and constitutive equation of the beam element. The governing equations for primary equilibrium path for beam under axial force and uniform bending moment is derived using equilibrium equations and constitutive equation of the second order beam theory. The exact solution of the primary path is solved using an analytical and numerical combined method. To derive the governing equations for laternal-torsional buckling analysis, disturbing nodal displacement and rotation vectors are applied to the primary path of beam elements. Then element coordinates corresponding to this disturbance can be constructed, and element nodal rotation parameters defined in this element coordinates can be determined in terms of the disturbing nodal displacement and rotation vectors. The governing equations for laternal-torsional buckling analysis are derived in this element coordinates by using the first order linearization. A power series solution method is used to solve the buckling moment for spatial beams under axial force and different types of end moment to demonstrate the accuracy and effectiveness of the proposed method. Numerical examples are studied to investigate the effect of compressive force on the buckling moment of spatial beams.
Hsu, Hung-Yi, and 徐宏一. "Measurement of Axial Stress and Bending Curvature by Side-Polished Fiber Grating Sensors." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/71960631459378546852.
Повний текст джерела逢甲大學
電機工程所
98
To enhance the sensing sensitivity of fiber gratings, we used the side-polished technique to remove parts of cladding to reduce the thickness of fiber. The long-period and short-period fiber gratings have different response characteristics and sensitivities for the bending curvature and axial stress. Therefore, we can manufacture various types of fiber sensors based on the side-polished technique. In this research, we make long-period and short-period fiber gratings sensing elements with different polishing thicknesses based on fiber gratings writing and side-polished techniques. These sensing elements can be used to measure the axial stress and the cantilever bending curvature. The grating length and the effective polishing length are 2 centimeters. The sensing range and sensitivity are 0−124.73 MPa and 0.020 nm/MPa for axial stress and 0−0.066 m-1 and 16.95 nm/ m-1 for cantilever bending curvature, respectively. We presented a novel structure combined with long-period and short-period fiber gratings. This sensing structure used for measuring multi-parameters such as axial stress, cantilever’s bending curvature and bending directions.
Young, Y. S., and 楊育碩. "Mechanical Ratchetting of a Stepped Beam under Steady Axial Tension and Cyclic Bending." Thesis, 1993. http://ndltd.ncl.edu.tw/handle/59811028001197578677.
Повний текст джерелаChung, Youngjin. "Buckling of composite conical shells under combined axial compression, external pressure, and bending." Thesis, 2001. http://library1.njit.edu/etd/fromwebvoyage.cfm?id=njit-etd2001-099.
Повний текст джерелаchen, Hsin-pu, and 陳信甫. "Numerical Analysis of Thin-Walled Composite Box Beam under Combined Bending and Axial Force." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/35885609329526607577.
Повний текст джерела國立成功大學
土木工程學系碩博士班
97
A nonlinear failure mode had been used for studying and predicting material failure under the condition of thin-walled composite box beam and subjected to combined bending and axial force. This nonlinear failure mode including three parts: first, the nonlinear constitutive law of material before failure; second, the mixed failure criterion to predict the time of failure; third, the analysis of post failure mode. The simulation of nonlinear mode before failure for the thin-walled composite box beam is assumed that lamina is plastic-elastic in axial and transverse directions, and using constant shear parameter in in-plane. The mixed failure criterion, combining the excellence of Tsai-Wu theory and maximum stress theory, had been used for judge failure timing. During analyzing of post failure mode for the thin-walled composite box beam, the brittle failure mode had been adopted in axial, shear and transverse direction. The result of the nonlinear failure mode will compare with the experimental data of thin-walled composite box beam subjected to bending to verify the mode in this study correct. Finally, using the models in this study discuss the thin-walled composite box beam under the different length, section size, order of laminates, and bending-axial forces to apply in engineering.
Tsai, Hung-Yu, and 蔡宏裕. "Study on Interaction Behaviors of RC Columns Excited by Axial Force and Biaxial Bending." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/6u9jpa.
Повний текст джерела國立臺北科技大學
土木與防災研究所
95
This thesis proposed a set of visualized operation system for the analysis on interaction behaviors of RC columns excited by axial force and biaxial bending. Incorporating with equilibrium and compatibility condition, the constitutive law of concrete proposed by Kawashima et. al. as well as the elastoplastic model of reinforcement was taken into account mechanically. By necessary comparisons, a good consistency can be found between the analysis results and the results obtained by conventional load contour method. To testify the accuracy and validity of the proposed approach, twenty-six reported results of bidirection-eccentry tests of RC columns were adopted for necessary investigation. It shows that this study can provide an acceptable result and might benefit the paractial design efforts for structural engineers.
Ali, Usman. "Numerical Modeling of Failure in Magnesium Alloys under Axial Compression and Bending for Crashworthiness Applications." Thesis, 2012. http://hdl.handle.net/10012/6511.
Повний текст джерелаTsai, Shih-Heng, and 蔡世桓. "Nonlinear Analysis of Double-Skin Concrete Filled Tube Subject to Axial Compression and Bending Moment." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/86723765577269248263.
Повний текст джерела國立成功大學
土木工程學系碩博士班
94
This paper use ABAQUS software to analyse the Double-Skin Concrete Filled Tubes (DS-CFT) that subject to axial compression and bending moment, then compare the analysis results with experimental data of national earthquake center. By the way, we can find the Fl, K3, and K4 of a DS-DFT subject to such loads, understand the benefit that concrete can produce in DS-CFT so, and calculate the experience formulas used for material parameters. By the result analysing, we can find that the specimen under pure bending can’t let the concrete keep its compressive resistibility because of lacking the axial compression, therefore the strength of such specimen is less than others, but DS-CFT can still offer a certain Fl that is much stronger than CFT. Besides, we find the experience formula and K2 of CFT are not suitable for DS-CFT specimens, K2 value of CFT will lead to a strain that is too large. so this paper repeated trying for many times, induct new values of K2, and find out the suitable material parameters and experience formulas again.
Hsieh, Wu-Teng, and 謝武燈. "On Draw Bending Process of a Metal Tube in Small Bend Radius with Axial Load." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/31743402312239187610.
Повний текст джерела國立中興大學
機械工程學系
93
Nowadays, becoming lighter and smaller is an important direction for product design. Metal tubes which are broadly used to transport the materials and energy should therefore diminish their application volume without any weakening their function and losing the safety. For this reason metal tubes bent into small radius becomes more and more significant. However, in processing metal tubes into small bend radius, some defects will exist, such as hollows on them or thinning on their outer walls. These defects might lose the function of metal tubes. Thus this research attempts to modify the draw bending process which is mostly applied in the industry to bend the metal tube into small radius, so that the defects might be eliminated. A test platform with a stroke controllable mandrel and a mechanism pushing metal tube in the axial direction was setup. The mandrel positioning, axial loading, and bending speed as well as lubricant status are therefore investigated experimentally in this research. The experiment results show that there is no significant difference found between various bending speeds. Regarding lubrication on the tube inner wall, a stick slip phenomenon can be found during tube bending, if no lubricant is applied. By positioning the mandrel firstly deeper beyond the bend center and then moving back during the bending process to its normal position, the hollowing on the tube can be reduced. However, if the mandrel moves deeper during the bending process from its normal position, the wall thickness can be conversely thinned. An axial loading imposed on the tube bending process can reduce the flattening of the bent tube. Superposing an axial loading on the tube bent with a mandrel can induce an excellent cross-section of the bent metal tube. The results obtained in this research regarding the mandrel positioning and the imposed axial loading can be offered for tube bending application industry to improve the tube bending process particularly into small bend radius.
JIAO, XIAN-QI, and 焦先齊. "The influence of axial pressure on the coupled bending-torsion vibration of a rotating bladezeng." Thesis, 1992. http://ndltd.ncl.edu.tw/handle/65074334639215497893.
Повний текст джерелаHsu, Shuo-Hsiu, and 許碩修. "Lateral-Torsional Buckling Analysis of Bisymmetric Thin-Walled Beam under Axial Force and Nonuniform Bending Moment." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/49196229549752184772.
Повний текст джерела國立交通大學
機械工程系
90
In the study, the nonlinear lateral-torsional buckling analysis of bisymmetric thin-walled beam under axial force and nonuniform bending moment is investigated. The beam element developed in reference [1] is employed here. In reference [1], the co-rotational formulation, the virtual displacement method and the consistent second order linearization of geometric beam theory are used. An incremental-iterative method based on the Newton-Raphson method combined with constant arc length of incremental displacement vector is employed for the solution of nonlinear equilibrium equations. The zero value of the tangent stiffness matrix determinant of the structure is used as the criterion of the buckling state. A bisection method of the arc length is used to find the buckling load. The nonlinear lateral-torsional buckling moment and post buckling behavior of beams with different sections, lengths, and boundary conditions under axial force and nonuniform bending momen is investigated. The accuracy of results of the linear buckling analysis given in the literature is examined.
Lin, Yan-Xing, and 林彥興. "Delamination Growth Experiment and Analysis of Composite Laminates under Axial Compression、Transverse Loading and Pure Bending." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/36391501931458111322.
Повний текст джерелаHUANG, MING-HUI, and 黃明輝. "Elasto-plastic analysis of thin-walled tubes and beam subjected to steady axial load and cyclic bending." Thesis, 1991. http://ndltd.ncl.edu.tw/handle/72356379149993705403.
Повний текст джерелаHaremza, Cécile. "Robustness of open car parks under localised fire." Doctoral thesis, 2015. http://hdl.handle.net/10316/27324.
Повний текст джерелаO número crescente de carros a circularem na Europa nas últimas décadas, bem como o aumento de grandes centros comerciais, aeroportos e estações ferroviárias, aumentou consideravelmente o número de parques de estacionamento abertos. Uma maneira fácil e de baixo custo para a construção é a utilização de uma estrutura mista aço-betão. Em situação de incêndio, a combustão generalizada (flash-over) é improvável de ocorrer nesses espaços abertos, e devem ser considerados incêndios localizados. Um incêndio localizado, que se desenvolve num parque de estacionamento misto sem protecção contra incêndio, conduz ao aquecimento dos elementos estruturais mais próximos do incêndio: ligações, vigas e colunas. O colapso de uma coluna sujeita a incêndio localizado provoca grandes deslocamentos verticais nos andares superiores. Para atingir um equilíbrio nesta configuração deformada, e assim evitar o colapso progressivo do edifício, desenvolvem-se forças de membrana nas lajes e nas vigas. Portanto, durante este evento, as ligações viga-coluna estão sujeitas a sequências particulares de carregamento, envolvendo principalmente momentos flectores e esforços axiais. Essas ligações devem resistir à nova distribuição de esforços e ter ductilidade suficiente para poder sustentar grandes rotações, sem rupturas. Para tal, a estrutura deve ser dimensionada tendo em conta a robustez necessária para este evento acidental. O trabalho de investigação apresentado nesta tese está inserido no projecto Europeu RFCS ROBUSTFIRE, e no projecto Nacional IMPACTFIRE. As diversas fases deste trabalho estão relacionadas com um caso de estudo que envolve uma configuração estrutural de um edifício típico de parque de estacionamento aberto. O cenário considerado é o colapso de uma coluna devido a um incêndio localizado (combustão de veículos), e são consideradas as restrições axiais devidas à estrutura não afectada pelo incêndio. Este trabalho tem como principal objectivo o estudo detalhado do comportamento de uma ligação mista aço-betão viga-coluna com placa de extremidade, aquecida pelo incêndio localizado, quando está sujeita a momentos flectores e esforços axiais variáveis. Numa fase inicial, realiza-se uma revisão das regras práticas actuais, e o estado da arte sobre a concepção e avaliação de parques de estacionamento abertos sujeitos a um incêndio localizado. Em seguida, a investigação centra-se em estudos experimentais, numéricos e analíticos: i) Realizam-se sete ensaios experimentais em ligações mistas aço-betão viga-pilar sob diferentes combinações de momentos flectores e esforços axiais, considerando não só condições isotérmicas, mas também um cenário de temperatura transitória. ii) Desenvolvem-se modelos numéricos 3D detalhados da ligação mista, de forma a reproduzir os ensaios experimentais. iii) Finalmente, é estudado a influência de alguns parâmetros que afectam a robustez deste tipo de edifícios (tais como temperatura, vão da viga, tamanho da ligação, etc....), usando os modelos numéricos desenvolvidos e um procedimento analítico existente na bibliografia.
The growing number of cars in Europe during the last decades, as well as the amount of large shopping centres, airports and railway stations, have considerably increased the number of open car park buildings. An easy and low cost way for the construction of these open car park buildings is to use a composite steel-concrete structure. Under fire situation, flash-over is unlikely to occur in these opened compartments and localised fires should be considered. When a localised fire develops in an unprotected steel composite car park, it leads to the heating of some of the nearby structural elements: connections, beams and columns. The loss of a column under localised fire induces large vertical displacements in the above floors. To reach equilibrium in the deformed configuration and avoid progressive collapse of the building, membrane forces in the slabs, and catenary forces in beam elements should develop. So, during the event, the beam-to-column connections are subject to particular load sequences mainly involving bending moments and axial forces. These connections are also required to have sufficient ductility in order to sustain large rotations without brittle damages. Therefore, sufficient robustness should be provided to the structure at the design stage. The research work presented in this thesis is based on the European RFCS ROBUSTFIRE project, and the National IMPACTFIRE project. The various stages of this work are related to a case study involving a structural configuration that represents a typical open car park building. The considered scenario is the loss of a column due to a localised fire (burning cars), and the strong restraints to the beams provided by part of the building not directly affected by this accident are taken into account. The behaviour of steel-concrete composite beam-to-column joints in open car park buildings under column loss scenario, due to fire, is investigated in detail. The main objective is to provide a detailed analysis of the heated joint behaviour subject to variable bending moments and axial loads when the column fails. First, a review of current practice and state of the art in the design and assessment of open car parks subject to localised fire is performed. Then the investigation is based on experimental, numerical and analytical results: i) Seven experimental tests are performed on composite steel-concrete beam-to-column joints under different combinations of bending moments and axial forces, considering isothermal conditions, and also one transient temperature scenario. ii) Detailed 3D numerical models of the heated joint are developed to reproduce the experimental tests. iii) Finally, the influence of some parameters that affect the robustness of this type of building (such as temperature, beam span, joint size, etc.…) are studied using the developed numerical models and an existing analytical procedure.