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Design of Thick Concrete Beams : Using Non-Linear FEMTeklemariam, Daniel Mekonnen, Hamunzala, Bennie January 2016 (has links)
The experimental studies performed on the behaviour of very thick concrete beams subjected to static loads have revealed that the shear mechanisms play an important role in the overall response and failure behaviour. The aim of this thesis is to recommend suitable design methods for thick concrete beams subjected to off-centre static concentrated load according Eurocode 2 by using non-linear finite element analysis (NLFEA). To achieve this task, Abaqus/Explicit has been used by employing constitutive material models to capture the material non-linearity and stiffness degradation of concrete. Concrete damaged plasticity model and perfect plasticity model has been used for concrete and steel respectively. Three dilation angles (30º, 38º and 45º) and fracture energy from FIB 1990 (76 N/m) and FIB 2010 (142 N/m) has been used to investigate their influence on the finite element model. The dilation angle of 38º and FIB 2010 fracture energy was adopted as the suitable choice that reasonably matched with the experimental results. In verifying and calibrating the finite element model, the experimental results of the thick reinforced concrete beam conducted by the American Concrete Institute have been used. Three design approaches in the ultimate and serviceability limit state according to Eurocode 2 recommendations have been used namely; the beam method, strut and tie method and shell element method. Using the reinforcement detailing of the hand calculations of beam method and strut and tie method and linear finite element analysis of shell element method, non-linear finite element models have been pre-processed and analysed in Abaqus/Explicit. During the post-processing, the results have been interpreted and compared between the three design methods. The results under consideration are hand-calculated load at 0.3 mm crack width, FE-load at 0.3 mm crack width, amount of reinforcement and FE-failure load. The comparison of the results between the three design approaches (beam method, strut and tie method and shell element method) indicates that strut and tie method is better design approach, because it is relatively economic with regards to the quantity of reinforcement bars, has the higher load capacity and has a higher load at crack width of 0.3 mm crack width. / De experimentella studier som utförts på tjocka betongbalkar som utsätts för statisk last har visat att skjuvning spelar en viktig roll i brottmekanismen. Syftet med detta examensarbete är att rekommendera lämpliga dimensioneringsmetoder för tjock betongbalkar utsatt for statisk koncentrerad last enligt Eurokod 2 med hjälp av ickelinjära finita element metod. Abaqus/Explicit användes genom att utnyttja konstitutiva materialmodeller för att fånga materialens icke-linjäritet och minskad styvhet. Tre dilatationsvinklar (30°, 38° och 45°) och två brottenergi från FIB 1990 (76 N/m) och FIB 2010 (142 N/m) tillämpas för att kontrollera deras inverkan på FE-modellerna. Dilatationsvinkel med 38° och FIB 2010 med högre brottenergi valdes i de icke-linjära finita elementanalyserna. Kontroll av FE-modellerna är baserad på ”American Concret Institutes” experimentella resultat på de tjocka betongbalkarna. Handberäkningar av tjocka betongbalkar har utförts i brott- och bruksgränstillstånd med tre dimensioneringsmetoder i Eurokod 2 nämligen balk metoden, fackverksmetoden och linjära-FE skalelementmetoden. Jämförelse har gjorts för de olika dimensioneringsmetoderna, genom att använda de armeringsdetaljer av handberäkningar i de verifierade och kalibrerade icke linjära FE-modellerna i Abaqus/Explicit. Resultaten i fråga är last för 0.3 mm handberäknad sprikvidd, FE-last för 0.3 mm sprikvidd, armeringsmängd och FE-brottlast. Jämförelse av resultaten mellan de tre dimensioneringsmetoder (balkmetod, fackverksmetod och skalelementmetod) visar att fackverksmetod är bättre design metod, eftersom det är relativt ekonomiskt med avseende på armeringsmängd, har högre lastkapacitet och last på 0.3 mm sprickvidd.
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Static and fatigue design of load carrying welded joints in high strength steels : -In collaboration with Cargotec Sweden ABMumtaz, Noman Ali, Khurshid, Mansoor January 2011 (has links)
This thesis work is carried out in Cargotec Sweden AB, Bromma Conquip to study the behavior of load carrying welded joints in different weld metal strength mismatch conditions and various penetration ratios. Static and fatigue strength calculations have been made using FEA and experimentation. The joint in the Telescopic beam of the spreader STS45 has been analyzed. Telescopic beam is one of the critical and main parts in the spreader, which is directly subjected to the load of containers at various ports. Previous studies show that this joint limits the strength of the spreader, it has thus been analyzed. To check the effect of different strength mismatch conditions in the weld metal, static strength calculations have been carried out. The effect of different penetration ratios on static and fatigue strength has also been studied. A cruciform test specimen is designed according to the joint configuration and the capacity of testing machine. Criteria for the selection of consumables has also been developed and following standards: Eurocode 3, AWS D1.1 and BSK07, have been compared for static joint design. Sub modelling, effective notch stress and beam theory techniques have been used to study the effect of weld metal penetration and size of weld throat on the fatigue strength of the welded joint in the Telescopic beam. The study show that matching or slight under matching in the filler material along with full penetration increases the ultimate strength capacity as well as the ductility in the joint. Results of Eurocode 3, AWS D1.1 and BSK 07 are close to each other. Apart from strength mismatch and penetration ratios, it is observed that the weld geometry and joint preparation has also effect on the strength of the joint. Fatigue analysis of the weld in the Telescopic beam using 3D Finite element analysis show that effective notch concept is not applicable to this part of the spreader.
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Železobetonová rozhledna / RC Lookout TowerČírtková, Jana Unknown Date (has links)
The diploma thesis is focused on structural design and assessment of lookout tower, which is made of reinforced concrete and steel bracing elements. Structural design was performer in accordance with valid eurocodes and standards. The work is accompanied by construction drawings, drawings of shapes, reinforcement and steel elements, and documents from manufacturers.
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Městský most v Povážské Bystrici / Urban viaduct in Povazska BystricaKaut, Tomáš January 2022 (has links)
The content of the diploma thesis is design urban bridge in Považská Bystrica. From three possible options was selected one, which represents cable stayed bridge-extradosed with four spans. This selected option was elaborated in detail in this diploma thesis. Design procedures and assessments were performed to comply with ultimate limit state and serviceability limit state according to valid europeans standarts. The calculation model was performed in program Midas Civil in logitudinal axis and in SCIA Engineer in transversal axis. Structural assessment were done manually. The part of the diploma thesis are detailed drawings and visualizations.
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Železniční obloukový most / Railway arch concrete bridgeŠkrabal, Jan January 2022 (has links)
The subject of this diploma thesis is the structural design of a railway bridge over river Dyje based on materials given by my supervisor. The tied arch bridge with prestressed concrete girder is chosen for the structural check. The structural assesment is focused on prestressed concrete girder and basic calculations are made to check steel arch and hangers as well. Eigenvalue analysis provides dynamic properties of this structure. Appendices contain Structural design report, drawings including Construction stages scheme and visualization. For structural analysis Midas Civil software was used. Other used softwares for visualization, and outputs etc are: Lumion12, IdeaStatica, Microsoft excel and Autocad
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Železobetonová rozhledna / Reinforced concrete lookout towerKalinová, Kristýna January 2022 (has links)
The diploma thesis is focused on structural design and assessment of lookout tower. The elements of the lookout tower are made of cast-in-place reinforced concrete except for the stair flight, which is made of prefabricated reinforced concrete. The output of the diploma thesis is a structural design report and drawings of the shape and reinforcement. The calculations were performed using Dlubal RFEM 5.26.02. The drawings was processed by AutoCAD 2020 with the RECOC extension.
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Analýza spolehlivosti tlačených ocelových sloupů se stojinou obetonovanou betonem vysoké pevnosti / Reliability Analysis of Steel Columns with Encased Web in High Strength Concrete under CompressionPuklický, Libor January 2015 (has links)
The presented paper deals with a theoretical analysis of the ultimate limit state. The results of experimental research carried out at the Institute of Metal and Timber Structures headed by Assoc. Prof. Karmazinová and Professor Melcher were applied. The geometrically and materially nonlinear solution based on the Timošenko’s solution is verified by the FEM model in the computer programme system ANSYS. The random influence of initial imperfections is taken into consideration. The FEM model also includes the influence of residual stress. In the parametric study, the influence of residual stress on the cross-section plastification is researched into, its influence on the load carrying capacity limit is, together with the influence of other imperfections, the subject of the stochastic analysis, applying the Latin Hypercube Sampling (LHS). Further on, the study proves a direct effect of the concrete part of the cross-section (combination of materials steel-concrete) on the decrease of load carrying capacity limit of the beam caused by influence of the residual stress of steel. With regard to the importance of time dependent phenomena of the concrete creep for the load carrying capacity, the studies given in the Ph.D. thesis are oriented in this respect. The parametric studies of the influence of the concrete creep having applied the Standard Eurocode 2 provide both a comparison of load carrying capacity limits when using common and high-strength concrete types, and also the variability of load carrying capacities. It follows from the comparison of the statistical analysis outputs according to the design reliability conditions of the Standard EN1990 and of the approach of Eurocode 4 that the Eurocode 4 can be recommended for dimensioning of this member type. According to the studies which we carried out, the design in compliance with Eurocode 4 can be evaluated as the reliable one. A larger set of experimental data is necessary to determine the economy.
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Návrh mostu na silnici I/58 přes vodoteč a polní cestu / Design of Bridge on the road I/58Odvárka, Miroslav Unknown Date (has links)
This diploma thesis deals with the design of the bridge o the road I/58 over a watercourse and dirt road. The main content is the design and calculation of a continuous bridge structure with two bays. During designing the bridge, I based on Czech and European standards especially ČSN EN 1991 and ČSN EN 1992. A two-beam structure was selected from the developed three variants of bridging. Drawing documentation, construction procedure, visualization and static calculation were prepared for it. The result is an economical bridge structure with high durability and almost maintenance-free operation.
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Inlärningsålder och slutlig behärskning av talproduktion i andraspråket : Ett lyssnarexperiment om fonologisk vs icke-fonologisk brytning hos avancerade andraspråkstalare av svenska / Age of acquisition and ultimate attainment of speech production in the second language : A listening experiment of phonological vs non-phonological accent by advanced second language speakers of SwedishEriksson, Rasmus January 2022 (has links)
Föreliggande studie undersökte relationen mellan startålder och slutlig behärskning i fonologi och icke-fonologi (ett samlingsbegrepp för morfosyntaktisk och idiomatisk brytning). Deltagarna var 200 spansktalande andraspråkstalare av svenska, 20 modersmålstalare av svenska (kontrollgrupp) och 28 lyssnare med svenska som modersmål. Slutlig förmåga i fonologi och icke-fonologi mättes genom två brytningsbedömningar av lyssnargruppen, en där talarnas faktiska röster användes för att mäta fonologisk förmåga och en där en syntetisk röst användes för att mäta icke-fonologisk förmåga. Studiens resultat visade att det fanns en stark negativ korrelation mellan startålder och slutlig behärskning för både fonologisk och icke-fonologisk förmåga. Korrelationen var starkare för fonologi än för icke-fonologi. Starålder visades även vara den starkaste prediktorn för inföddlik slutlig behärskning, även efter kontroller av andra prediktorer som ålder, vistelsetid i Sverige och grad av andraspråksanvändning (% i förhållande till L1). Sannolikheten att tillägna sig en inföddlik slutlig behärskning var högre ju tidigare startålder talarna hade och endast talare med startålder mellan 1 och 16 uppvisade inföddlikhet i både fonologi och icke-fonologi. Fler talare uppvisade inföddlikhet i icke-fonologi än i fonologi, vilket kan bero på den unika motoriska begränsning tillägnande av fonologi har.
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Cultivating Identity and the Music of Ultimate FightingDavis, Luke R. 10 July 2012 (has links)
No description available.
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