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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Příprava realizace železničního viaduktu v Ostrově nad Oslavou / Preparation and realization of the railway viaduct in Ostrov nad Oslavou

Šťastný, Jiří January 2016 (has links)
This Diploma thesis deals with the preparation of the realization of the railway viaduct in Ostrov nad Oslavou. Realization of major technological stages is addressed in building technological study. Technological processes of each sub-job phases are supplemented by technical regulations, the design of the main building machines and mechanisms, inspection and test plan, schedule of occupational health and safety, time and financial plan construction, construction budget, a plan for securing material resources. I also worked out the technical report of the building sites facilities including drawings needed. I also worked out design rehabilitation of the substructure of the railway viaduct, which is consist of technical regulations for remediation work and drawings.
102

Ocelová konstrukce mostu na pozemní komunikaci / Steel structure of the bridge on the road

Vlček, Radek January 2016 (has links)
The content of the thesis is a proposal of steel load-bearing structure (carrying structure of a steel) bridge of the span of 31+74+31m with the bottom bridge deck taking over the second-class road in the territory of Olomouc city. The bridge deck is created by composite steel-concrete slab with crossbars. The solution was focused on using arched construction in the middle of the bridge with different tilt of arches to the horizontal central axis of the bridge. Under the term of the solution four alternatives have been calculated. The most optimal solution was selected and processed in detail. The calculations were made in compliance with the Czech technical norms ČSN EN.
103

Stanovení hydrodynamického zatížení přelévané mostovky s využitím 2D numerických simulací / Quantification of hydrodynamic load on overflowed bridge deck using 2D numerical simulation

Pavlíček, Michal January 2016 (has links)
The diploma thesis is focused on a quantification of hydrodynamic load of overflowed bridge deck. Solution was pursued by using two–dimensional numerical simulation of open channel flow in vertical plane created in ANSYS 15.0 software (modules: Workbench, Design Modeler, Meshing, Fluent). Values of drag force, lift force, moment, drag coefficient, lift coefficient and moment coefficient is result of computation. Various types of bridge decks were tested in relation to the degree of inundation (inundation ratio) and flow velocity.The thesis provides comparison of numerical simulation with physical experimental testing and result published in accessible resources.
104

Lávka pro pěší v Blansku / Footbridge in Blansko

Urbánek, Jan January 2017 (has links)
The subject of the thesis is design and check of steel load-bearing structure of a footbridge. The footbridge spans the river Svitava in the town Blansko. The span length is 24 metres. The structural design is spatial bar structure with two main trusses. The upper and lower chords are curved in the shape of circular arch and they are connected by diagonal bars. In the level of the upper and lower chords the beams are connected by floor beam. Horizontal rigidity of the upper and lower construction area is secured by bracings. The bridge deck is laid on the lower floor beam. The solution is the result of the comparison and evaluation of two variants.
105

Lávka pro pěší a cyklisty ve městě Zvolen / The footbridge for pedestrians and cyclists in Zvolen

Hric, Fedor January 2017 (has links)
Diploma´s thesis is about timber structure of footbridge for pedestrians and cyclists over the Slatina river in the city of Zvolen as cast of alternatives. In the first alternative is footbridge designed as a simple arched beam, made of glued laminated timber. Footbridge is also designed with semi through bridge deck, made of structural timber. The second alternative is designed as a tied arch structure. At this alternative is the bridge deck left unchanged(material, sizes of members). Both alternatives are attested by currents standarts.
106

Jämförelse av beräkningsmetoder för lastspridning i tvärled vid brobaneplattor av betong / Comparison of calculation methods for lateral load distribution in concrete bridge decks

Emilia, Wallin January 2015 (has links)
Denna studie har till syfte att undersöka hur lastfördelningen och följaktligen dimen­sionerande tvärkrafter och moment i brobaneplattor av betong skiljer sig åt beroende på val av beräkningsmetod. Jämförelsen sker primärt för tre utvalda hand­beräknings­metoder som jämförts med beräkningar gjorda i ett beräknings­program baserat på finita element­metoder (FEM). I jämförelsen undersöks hur laster sprids i brobaneplattan enligt de olika beräknings­metoderna och vilka resulterande maximala snittkrafter som erhålls. Hur lastfördelningen sker är en komplex fråga och det är därför intressant att se vilka skillnader det blir i resultat utifrån olika beräknings­metoder. Studien skedde på ett utvalt studieobjekt, en åtta meter bred samverkansbro i Njurunda strax söder om Sundsvall. De trafiklaster som beaktats är lastmodell 1 och lastmodell 2 enligt Eurokod (CEN, 2003). De beräknings­metoder som jämförts i den här studien är dels en metod för beräkning av tvärgående konsol­moment där kantbalken bidrar mycket till den lastspridande effekten. En annan metod är för beräkning av tvärkraftsfördelning vilken generellt anses mycket gynnsam, alltså ger små tvärkrafter att dimensionera bron utifrån. Den tredje och sista handberäkningsmetoden som studerats är beräkningar av tvärgående moment i fältmitt, med hjälp av influensytediagram. Influensytediagrammen som dessa studier baseras på är fram­tagna av Adolf Pucher (Pucher, 1977) och kallas ibland för Pucherdiagram. Finita element­modeller (FE-modeller) skapades för jämförelse av resultat från hand­beräkningar. Flera olika FE-modeller skapades med varierande detaljnivå, för att kunna se hur modelleringstekniken påverkar resultatet. I alla FE-modeller har bro­bane­plattan modellerats som skalelement eftersom detta är det vanligaste sättet att modellera en bro med FEM. Skillnaderna mellan de olika FE-modellerna är framför allt hur huvudbalkarna modellerats. Även ytterligare en handberäkningsmetod tillämpades för respektive snittkraft för att ge ytterligare en referens. Referensmetoderna valdes för att vara enklare metoder som baseras på andra randvillkor än de primära handberäkningsmetoderna i den här studien. Resultatet från studien visar att de förenklingar som finns i handberäkningar kan ha signifikant inverkan på resultatet. Ett konstant förhållande mellan handberäkning och FEM, där den ena beräkningsmetoden alltid resulterade i större snittkrafter, kunde inte konstateras rakt igenom studien. För tvärgående konsolmoment gav hand­beräkningen ett större maxmoment samt att en del skillnader kunde avläsas FE-modellerna emellan. Vid beräkning av tvärkraft gav FE-beräkningen ett resultat som var nära på det dubbla av det resultat handberäkningen gav. För Pucherdiagrammen blev resultaten varierade och det fanns ingen tydlig indikation för om handberäkningar ger större eller mindre tvärgående moment än en FE-modell. Studien resulterade bland annat i ökad kunskap om att förenklingar, vid dimen­sionering av en bro med hjälp av handberäkningar, kan ha stor betydelse för resultatet. Då förenklingar vid handberäkning inte går att välja av användaren finns en fördel med FEM. Fördelen med FEM är då att förenklingar styrs av användaren och det går även att studera vilken effekt en viss förenkling ger. En annan slutsats var att betong är ett material som har ett komplext beteende och i metoder som bygger på empiriska studier kan lättare få med olika effekter som finns i en verklig brobaneplatta av betong. / The aim of this thesis is to study different design methods for determing load distribution, and design values for shear force and bending moment in concrete bridge decks. The study was performed based on three design methods for hand calculations, which have been compared to the results from finite element modelling (FEM). The load distribution has a major impact on the design of a bridge and how the results from different design methods will correlate is of a great interest. The evaluation has been performed on one case study, wich is an eight-meter wide composite girder bridge in Njurunda, situated south of Sundsvall in Sweden. The traffic loads applied for this study was load model 1 and load model 2 prescribed in Eurocode (CEN, 2003). One of the design methods investigated is a method used to determine for bending moment for a cantilever slab. A significant impact from the edge beam utilizes by the method to calculate the bending moment. The second method is a design method for shear forces recommended by The Swedish Transport Administration. The third and last design methods for hand calculation is to use influence charts by Pucher (Pucher, 1977). By using the influence chart to calculate the maximum bending moment in mid-span. Results from different models, created with FEM, were compared to the results from hand ­calculations. The bridge slab was modelled with shell elements, and the girders of the bridge were modelled in four different ways to study the impact of the level of detail in the numerical models. The results in this report show that hand calculation methods are based on significant simplifications of the structure and these may have a major impact on the results. The relation between results from hand calculation methods and results obtained with FEM was not consistent in all cases analysed. While studying the bending moment for a cantilever slab, the main conclusion was that the simplifications in the hand calculation methods resulted in significantly higher moments compared to the FE-calculations. Regarding design for shear forces, the FE analyses resulted in nearly twice as high shear forces compared to the hand calculation methods. While using the influence charts by Pucher the relation between results from hand calculations and results from FEM was not consistent. Conclusions from the study included that the simplifications in hand calcu­lations is hard to change. These simplifications can have a major influence to the results. Some simplifications will make the results more on the safe side. With FEM the user is more free to choose which simplifications that will be made, but it can sometimes be hard to see the effect simplifications have on the results. Concrete is a complex material and design methods based on empirical studies does most likely give a result that reflects the reality better than methods based on mathe­matic theories.
107

Obloukový silniční most / Highway arch bridge

Vavřička, Lukáš January 2022 (has links)
The aim of the master thesis was a design of arch highway bridge made of prestressed reinforced concrete. In the beginning two versions of construction were designed, with box-girder and double-girder cross section of bridge deck, from which the variant of double-girder cross section in combination with box-girder arch were chosen for further detail postprocessing. The basics of the solution laid in right choice of dimensions of elements creating load-bearing system and construction geometry. Subsequently global beam model was created, which was used to prestress design and structural assessment of ultimate and serviceability limit states of pillars, arches and bridge deck during the building phases, service lifetime and in the end of lifetime of construction. For detail assessment, linear and nonlinear analysis was created using Midas Civil. To check the cross-sectional direction of bridge deck, slab model was made using Scia Engineer software
108

Příprava realizace předpínaného mostu v obci Hnojník / Preparation for the implementation of a prestressed bridge in the village of Hnojník

Stupka, Matouš January 2022 (has links)
The subject of this diploma thesis is the preparation for the implementation of a prestressed bridge in the village of Hnojník. This thesis contains a technical report, coordination situation of the construction with broader relations to transport routes, phases time shedule, a feasibility study of the main technological phases, project of construction site equipment, a suggested list of the main construction vehicles and building mechanisation, time shedule of main construction, shedule of transport of fresh concrete mixture, technological regulation of concreting bridge deck, technological regulation of additional prestressing bridge deck, control and test plan, health and safety at work on bridge construction, The annexes contain drawings of concept of load-bearing falsework, drawing of the construction site equipment, drawing of coordination situation of the construction with broader relations to transport routes , itemized budget, graph of workers and machines needs, phases time shedule and delivery shedule of fresh concrete mixture.
109

Železniční most přes Váh mezi obcemi Nemšová a Trenčianska Teplá / Rail bridge over river Váh between Nemšová and Trenčianska Teplá

Lezová, Lívia January 2022 (has links)
The diploma thesis is focused on the design of a new steel structure of a single-track railway bridge with bottom bridge deck. The solved bridge construction is located on line No. 123 between Nemšová and Trenčianska Teplá at the point, where the line crosses over the river Váh. The existing bridge on the line has a span of 50 + 50 + 50 + 50 m. The assignment was processed in five variants of a steel bridge structure with a bottom orthotropic deck. Each variant has a different static system, a different number of fields and a different type of superstructure. The comparison of variants was performed using multicriterial evaluation based on selected criteria. The most suitable variant was elaborated in more detail. The calculations were performed according to valid ČSN EN standards.
110

Půdorysně zakřivená oblouková lávka pro pěší / Plan curved arch footbridge

Trenz, Jan January 2012 (has links)
The scope of thesis is to design a curved arch footbridge. The main structure consists of composite deck supported by steel arch. The focus is on finding optimal shape of arch and proper cross-sections of elements. Bridge is analysed according to limit states.

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