The design of a bolted joint shall consider several factors such as material and heat treatment of the bolt (defined by the class of the bolt), stiffness of the parts being assembled (stiffness of the union), dimensions of the bolt, among others. In our study we used bolts M6x1, class 8.8, with three different lengths: 40 mm, 60 mm and 80 mm. The purpose of this study is to verify the relationship between the length of the bolt and the fatigue limit of the bolted joints, subjected to fluctuating cyclic loading of tension. The results indicated that the greater the length of the bolt, the larger the fatigue limit. An analytical study was also evaluated on the relationship between the cyclic stress amplitude and the mean stress experienced by the bolts with 40 mm of length. The results were compared with the bolt fatigue diagram of the BURGUETE and PATTERSON (1995). Correction factors were proposed for the relationship between cyclic stress amplitude. The adapted model from LEHNHOFF and WISTEHUFF (1996) for M6 bolts was the one whose results were the closest to estimated. / O projeto de uma união parafusada deve considerar diversos fatores tais como material e tratamento térmico do parafuso (definidos pela classe do parafuso), rigidez das peças que estão sendo montadas (rigidez da união), dimensões do parafuso, entre outros. Em nosso estudo utilizamos parafusos M6x1, classe 8.8, com três comprimentos distintos: 40 mm, 60 mm e 80 mm. A proposta deste estudo é verificar a relação do comprimento do parafuso com o limite de fadiga de uniões parafusadas submetidas a carregamentos cíclicos de tração. Os resultados indicaram que quanto maior o comprimento do parafuso, maior é o limite de fadiga. Foi realizado ainda um estudo analítico da relação entre a amplitude de tensão e a tensão média suportada pelos parafusos de 40 mm de comprimento. Os resultados foram comparados com o diagrama de BURGUETE e PATTERSON (1995). Foram propostos coeficientes de correção para a relação entre as amplitudes de tensão. O modelo de rigidez adaptado de LEHNHOFF e WISTEHUFF (1996) para parafusos M6 foi o que apresentou resultado mais próximo aos estimados.

Cette étude porte sur la simulation dynamique de structures présentant des interfaces non linéaires et plus particulièrement sur le développement de diverses extensions à la méthode de balance harmonique. Cette méthode, qui permet le calcul de réponses vibratoires stationnaires, est basée sur l’approximation en série de Fourier tronquée de la réponse. En fonction de caractère plus ou moins non linéaire de la réponse, le nombre d’harmoniques à retenir pour approcher de façon satisfaisante la réponse peut être important et varier fortement sur l’ensemble de la plage de fréquence de simulation. Un des objectifs principaux de cette recherche a été de proposer une stratégie de calcul qui permette d’adapter le nombre d’harmoniques à chaque fréquence. Dans l’optique d’approcher le mouvement global de la structure, la méthodologie proposée se base sur le suivi de l’énergie de déformation du système en fonction de la richesse du contenu fréquentiel. La formulation développée reste simple à calculer et compatible avec les étapes de condensation interne à la méthode de balance harmonique. L’extension de cette technique au calcul de réponses quasi-stationnaires est en outre possible en redéfinissant les stratégies de choix des harmoniques à retenir. Parallèlement à ce but principal, la présence de variables internes dans les modèles non linéaires d’interface (modèle de frottement par exemple) a été prise en compte dans la formulation des équations de la balance harmonique adaptative. Ces méthodes spécifiques ont ensuite été mises en oeuvre sur des modèles numériques de structures aéronautiques. Un isolateur d’équipement utilisant un matériau viscoélastique non linéaire a ainsi pu être simulé. Ensuite, la méthode de balance harmonique adaptative a pu être appliquée à l’étude des effets dynamiques non linéaires observée sur les structures boulonnées. Enfin, le calcul de réponses quasi périodiques s’est effectué sur un tronçon de lanceur intégrant des amortisseurs à frottement sec. / The study deals with the dynamic simulation of structures with non linear interfaces and particularly with the development of various extensions of the harmonic balance method. This method, applied for steady state vibrations, is based on the response approximation with a truncated Fourier series. Depending on the more or less pronounced non linear response behavior, the number of harmonics to retain to correctly approach the response may be important and may strongly vary over all the frequency band. One of the main objectives of this research work has been to propose a calculation strategy which allows adapting the number of harmonics for each frequency. In order to globally approach the structure vibration, the proposed methodology basics is to observe the strain energy evolution functions of frequency contents. The developed formulation is easy to calculate and may be employed with internal reduction steps of the harmonic balance method. Moreover, an extension of this technique for quasi-periodic vibrations is possible by redefining harmonic choice strategies. In conjunction with this main objective, internal variables in non linear interface models (friction models for example) have been considered in a specific adaptive harmonic balance method formulation. Then, these specific methods have been applied on numerical aeronautical structure models. An equipment isolator integrating a non linear viscoelastic material has been simulated. Secondly, adaptive harmonic balance method has been employed for the study of non linear dynamic effects of bolted structures. Finally, quasi periodic vibration calculation has been carried out on a launcher stage integrating dry friction dampers.

The final thesis deals with the design of the steel loadbearing structure of the shopping center situated in Brno. The built-up floor area is 1973 m2 (L-shaped ground plan with dimensions 48 m x 50 m). The construction consists of three parts. Building A has four above-ground floors and reaches a height of 25.5 m. The steel structure of mono-pitched roof is designed in two options. Both options consist of full-length purlins and truss girders. Building B is a single-storey building with a mono-pitched roof top reaching 8.1 m high. Building C is three-storey with a flat roof. The first floor has a construction height of 4.5 m and the remaining two floors reach height of 3.6 m, which coincide with building A. The steel structure is made of steel-concrete composite ceilings and pin-supported columns. In the case of bracings, pressure was eliminated by means of non-linearities.The work includes proposal, assessment of the supporting structure and calculation of the directional details. Internal forces were determined based on a static analysis in the SCIA Engineer calculation program.

Master's thesis is follow up with the disign of the load bearing structure of a office building. The building is designed for the area of Svitavy. The plan's dimension are 54,0 x 54,0 m. The objects has 10 floors. Load-bearing structure is disigned in two variants. In the variant A is centre to centre spacing 6m, in variant the B it si 9m. The coulomns and floor structure are composite steel-concrete. Thesis includes drawings.

The aim of this diploma thesis is the design of the roofing of an ice hockey stadium situated in Žďár nad Sázavou. Plan view dimensions are 55 m x 77 m. The structural height of the roof varies from 10 to 17 m. The roof itself consists of pipe truss girders with a span of 55 m, which are supported by columns on each side. The girders are suspended by a load-carrying arch with a span of 96 m and a camber of 29 m through a system of pre-stressed cables. To determine the internal forces, structural analysis software Scia Engineer was used. Individual elements were then manually designed.

The goal of the submitted thesis is a design and assessment of a steel load-bearing structure of a multipurpose sports hall situated in Prostějov. The floor plan measurements of the object are 38x54 m with the maximum ceiling height of 9,5 m. Final design variant was chosen on the basis of two preliminary drafts, both processed according to standard ČSN EN. The structure is designed with respect to ultimate and serviceability limit states. The construction consists of 10 cross-links spaced by 6,0 m. The spatial rigidity of the structure’s main load-bearing system is provided by spatial elliptic trussed girders, longitudinal and sway bracings. Roof cladding is carried by purlins placed on trusses. Steel columns are designed as a part of gable walls. The project was carried out in Scia Engineer 2014 software. Some particular elements were subsequently assessed by means of manual calculation. The thesis also includes assessment of joints, construction details and drawing documentation.

In the master’s thesis an educational task concerning an experimental apparatus for quantity measurement in preloaded bolted joint is realised. In terms of its preparation an innovation of the apparatus leading to an easier and faster pretension realisation was implemented. The educational task for students and also teaching material were produced. The educational task itself consists in experimental confirmation of the relation between the tightening torque and the caused pretension. An FEM model simulating an apparatus flange deformation by given pretension was designed to verify the experiment. The thesis also contains information about the preloaded bolts, pretension elicitation methods and pretension control methods.

V současnosti jedna z metod spojování zejména tlustých a vysoce zatížených kompozitních komponent je šroubový spoj, který je možné rozebrat pro případ opravy na rozdíl od lepeného spoje. Kompozitní konstrukce se tradičně dimenzují tak, aby během provozu nedošlo k porušení první vrstvy laminátu, nicméně důležité je taky poznat chování laminátu po porušení první vrstvy. Pro strukturální analýzu nejenom spojů, ale také dalších komponent se používá metoda konečných prvků a protože moderní nelineání řešiče jsou schopné modelovat chování laminátu po porušení první vrstvy, tato schopnost jednoho z nich byla využita v této práci při zkoumaní chování sklolaminátu spojeného s hliníkovou částí šrouby. Konečno-prvkové modely dvou spojů kovové a kompozitní části konstrukce schopné popsat progresivní porušování laminátu byly postaveny s využitím tří různých poruchových kritérií – kritéria maximálního napětí, kritéria Hill a kritéria Tsai-Wu. Problém byl řešen s využitím řešiče Nastran. Křivky síla-posuv, tuhost-posuv a hodnoty zatížení při hraničním posuvu byly porov-nány s výsledky experimentů. Jelikož faktor zbytkové tuhosti ovlivňuje výsledky ana-lýzy progresivního porušování, byly provedeny citlivostní studie zkoumajíci vliv faktoru na přesnost a stabilitu výpočtu. Shoda výpočtu s experimentem v případe prvního šroubového spoje je méně uspokojivá, nicméně shoda v případě druhého spoje, který má zesilující tenkou ocelovou destičku na spodní straně, je podstatně lepší. Vý-borná shoda je zejména při použití interaktivních kritérií Hill a Tsai-Wu.

In my diploma thesis I designed 2 options for an arch roofing of place for dancing next to the restaurant in Dolní Jablonná. The first solution was designed as a timber structure with internal supporting arch from glue laminated timber. The second solution was designed as a two pin-supported steel beam. These variants were predesigned and as the final solution was chosen the timber structure. I designed a rafter, a glue laminated arch, a purlin, an anchorage and field joints. The thesis is including drawings of the layout design, details and anchorage plans.

Master's thesis „Study of joints of frame steel structures“ examine certain analysis types of frame steal joints, which are analysed both by component method and by specialized software IDEA RS. Obtained results are compared by both methods, in terms of load-bearing capacity and in terms of stiffness. Theoretical joints stiffness calculation according to standard ČSN EN 1993-1-8 is included in the introductory part of the thesis. In the second part, joints are designed to bear inner forces and moments, which were created by load combination effects and then analysed.