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21	Caractérisation robuste de liaisons amortissantes avec dispositifs piezo-électriques pour la réduction de vibrations de structures / Robust characterization of damping joints with piezoelectric devices for the vibrational reduction of structures Karim, Yassine 02 December 2013 (has links) L'étude présentée dans ce document a pour objet l'étude de différents modes de réduction de vibrations dans les structures avec liaisons. Le premier mode étudié se base sur la dissipation d'énergie apportée par la déformation d' éléments piézoélectriques connectés à un circuit électrique adapté. Le second mode proposé se base sur la propriété de la liaison boulonnée à changer les fréquences propres d'une structure en fonction du serrage appliqué. Cette propriété est utilisée avec plusieurs lois de contrôle du serrage afin d'éviter les plages de fréquences critiques. Ensuite une étude probabiliste est effectuée pour déterminer la robustesse de la réduction de vibrations par rapport à la variation de certains paramètres du modèle. Cette étude de robustesse est effectuée à travers des méthodes stochastiques non-intrusives, parmi lesquelles une méthode originale proposée. Elle permet une réduction de la taille du modèle stochastique à résoudre, ce qui réduit très considérablement le temps de calcul sans perte de qualité significative. / The study presented in this thesis aims to explore other ways of vibration reduction in structures with bolted connections. The first way studied is based on the energy dissipation provided by the deformation of piezoelectric elements connected to an adapted electric circuit. The proposed second way is based on the property of the bolted joint of changing the natural frequencies of a structure according to the applied tightening force. This property is used via several control laws to avoid vibration on critical frequency ranges.Thereafter a probabilistic study is made to determine the robustness of the vibration reduction in relation to a variation of some model parameters. The robustness study is done through non-intrusive stochastic methods, among them a dedicated method that we propose. A stochastic model reduction is allowed which reduces dramatically the computation time without losing quality of stochastic results. Réduction de vibrations Piézoélectrité Shunt Joint boulonné Frottement sec Contrôle passif et actif Robustesse Méthode stochastique non intrusive Vibration reduction Piezoelectric Shunt Bolted joint Dry friction Passive and active control Robustness Stochastic non-intrusive method 620.3
22	Efeito do comprimento do parafuso e da rigidez da união no limite de fadiga de uniões parafusadas / The Effect of bolt length and of joint stiffness in the fatigue limit of bolted joints Silva, Marcio Erick Gomes da 16 August 2013 (has links) 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. Materiais Resistência de materiais Deformações e tensões Parafusos Fadiga Pré-carga Comprimento do parafuso Rigidez da união parafusada Materials Materials Strains and stresses Fatigue Preload Bolt's length Bolted joint stiffness
23	Obchodní a nákupní centrum v Brně / Trade House in Brno Serbousková, Kateřina January 2018 (has links) 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.
24	Realizace edukační úlohy na experimentální stanici pro modelování předepjatých šroubových spojů / Realization of educational problem based on preloaded bolted joint apparatus Žaba, Tomáš January 2011 (has links) 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.
25	Přístřešek restaurace s tanečním parketem / Restaurant dance floor shelter Horský, Vojtěch January 2017 (has links) 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.
26	Studie styčníků rámových ocelových konstrukcí / Study of joints of frame steel structures Cikánek, Ondřej January 2017 (has links) 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.
27	Fügbarkeit von CFK-Mischverbindungen mittels umformtechnischer Prozesse Wilhelm, Maximilian 19 May 2016 (has links) (PDF) Kohlenstofffaserverstärkte Kunststoffe sollen in kommenden Fahrzeugprojekten in verstärkter Weise zur Reduzierung des Karosseriegewichtes beitragen. Neue Werkstoffe und Einsatzbedingungen erfordern jedoch in gleichem Maße angepasste Konstruktionen und innovative Fügetechnologien. Um die Realisierung der Gewichtseinsparpotenziale in wirtschaftlich attraktiver Weise zu ermöglichen, muss daher die Fügbarkeit von CFK-Stahl-Verbindungen mittels umformtechnischer Prozesse gewährleistet werden. Insbesondere der bisher unbekannte Einfluss von Fügeimperfektionen stellt in diesem Zusammenhang eine entscheidende Hemmschwelle für den industriellen Einsatz von CFK im Karosseriebau dar. Um sowohl die Einflüsse von Seiten des umformtechnischen Fügens als auch des werkstofflichen Einsatzgebietes CFK zu berücksichtigen, werden im Rahmen dieser Arbeit alle Teilgebiete der Fügbarkeit inklusive der Wechselbeziehungen zwischen Werkstoff, Konstruktion und Fertigung analysiert. Aus dem Verständnis der Fügbarkeit als ganzheitliche, globale Querschnittsfunktion und der damit notwendigen Einbeziehung der Produktentstehungs- und Produktnutzungsprozesse wird zudem eine Ergänzung der Fügbarkeit um den Prozesskettengedanken vorgenommen. Durch analytische und experimentelle Betrachtungen wurde eine auf Regressionsanalysen basierende Methodik, bestehend aus der Einbringung, Quantifizierung und Einflussbewertung von Imperfektionen, entwickelt und validiert. Über diese Methodik kann der Einfluss von Fügeimperfektionen gezielt untersucht und beschrieben werden. Die getätigten Untersuchungen wurden zudem zur Weiterentwicklung geeigneter Fügeverfahren für den Einsatz bei CFK-Mischverbindungen genutzt und die gesammelten Erkenntnisse anschließend in Konstruktionshinweise überführt. Nach der Bewertung aller Herausforderungen, die für das Fügen in der automobilen Prozesskette wesentlich sind, kann die Fügbarkeit von CFK-Mischverbindungen mittels umformtechnischer Prozesse als gegeben betrachtet werden. Somit ergibt sich für CFK als Leichtbauwerkstoff, neben der Luftfahrtindustrie, in der Automobilbranche ein weiteres Einsatzfeld im Transportwesen. Die in dieser Arbeit präsentierten Ergebnisse dienten so auch als Grundlage für den weltweit ersten industriellen Einsatz des Halbhohlstanznietens bei CFK-Stahl-Verbindungen im neuen BMW 7er. Fügeimperfektionen Bauteilimperfektionen Scherbruch Lochleibungsversagen Flankenzugbruch Fügbarkeit Mischbau Halbhohlstanznieten Fließformschrauben Blindnieten CFRP imperfection delamination shear-out failure bearing failure tension failure non-destructive testing bolted joint ddc:620 rvk:ZM 8415 rvk:ZM 8405 rvk:ZM 7023 CFK Faserverstärkter Kunststoff Fügen Verbindungstechnik Stanznieten Kleben Karosseriebau Faserverbundwerkstoff Delamination Zwischenfaserbruch Zerstörungsfreie Werkstoffprüfung
28	Ocelová konstrukce výstavního pavilonu / Steel construction of an exhibition pavilion Wawreczka, Karel January 2018 (has links) The aim of diploma thesis is to design steel roof structure of minimum dimensions 45 m x 50 m and minimum height 12 m. The plan of the building design has dimensions of 52,14 m x 70, 00 m and height is 18,68 m. The roofing was design as 3D truss girders with two lower chords and one upper chord. The shape of 3D truss girder consists of three circular arcs of radius 69,88m, 12,43 m and 33,45 m. Between main girders is 3D bracing. The structure is pin-supported.
29	Ocelová konstrukce vojenského muzea / Steel structure of a military museum Šašinka, Jakub January 2015 (has links) The diploma thesis describes the design and assessment of steel structure of the roofing of the military museum in Králíky. The supporting structure of hall is 40.00 meters span. The total layout are 55.93 x 72.04 m, building height 11.43 m, 16.11 m pylon height. Main construction material is steel, grade S355, secondary constructions are made from steel grade S235, rods are made from steel grade S460. I did optimization of steel structure and chose the best option. For this option I made detailed structural analysis. It is prepared by static analysis of the main load-bearing parts of the structure, including joints and details. The supporting structure of hall consists in the transverse direction from the curved spatial lattice structure made of steel circular tubes which hang on rods on a sloped pylon. Part of the report is open-air roofing.
30	Trojlodní objekt pro průmyslovou výrobu. / Three-Aisled Steel Building Lečbych, Antonín January 2015 (has links) The thesis contains the design and assessment of three-aisled steel building for small metal production. Supporting span of construction hall is 9, 18 and 9 m. In the middle wing is situated bridge crane with capacity of 2 tons. The estimated location of the object is Luhačovice. The initial design concept was specified by supervisor (as the idea of the investor/architect), for which was did static and structural solution and assembly details. For selected option was made a calculation of supporting structures and selected assembly details. The hall has a rectangular floor plan of 36x36m and ridge height is 9 m. The central wing is made of steel and side extensions are made of glued laminated timber.

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