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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.
11

Most přes místní potok / Bridge over a local brook

Růžička, Antonín January 2016 (has links)
Diploma thesis deals with design pre-stressed road bridge over the local brook and field road. There are designed 3 studies, from which variation trapezial point-supported pre-stressed concrete slabroad bridge with 3 spans is chosen. In the structural analysis of the bridge structure is assessed at the ultimate limit state and serviceability by European standards – Eurocodes. It is developed drawings and visualization of the bridge.
12

Most na dálnici D1 přes silnici a potok / Bridge on the D1 highway over a road and brook

Surovcová, Monika January 2016 (has links)
The aim of the diploma thesis is the proposal of a bridge structure in the direction of Přerov – Lipník in the cadastral territory of the Osek nad Bečvou. A bridge is used to overcome the road III/43612 in km 93,550, the stream Lubeň and a field trip. From tree alternatives is selected a post-tensioned two-beam concrete struction and assessed according to the limit states including an impact of phased construction according to the European standards. Also it is prepared a drawing documentation, an accompanying report and a visualization of the beam.
13

Most 203 na dálnici D1 v Považské Bystrici / Bridge No. 203 on the highway D1, Považská Bystrica

Mudrík, Marián January 2022 (has links)
The diploma thesis deals with alternative design of bridge on highway D1 near Považská Bystrica. Bridge is designed as composite steel-concrete bridge with 6 spans in length 35,7m + 42m + 42m + 42m + 42m + 35,7m. Overall length of superstructure of the bridge is 241m. Construction material used in design is steel S355, concrete C35/45 and reinforcing steel bars are grade B500B. Calculation of superstructure of two variants was performed in preliminary design. First variant is twin-girder structure system and box-girder structure system is second variant. Selected twin-girder bridge was developed in more complex structural design report. Direct erection in place with temporary piers was selected as assembly method of steel structure. Slab concreting will be done by mobile formwork. The design and calculation of the bridge structure was carried out according to valid European design codes. The diploma thesis includes engineering report, structural design report of variants, structural design report of final variant, bill of quantities of assembly parts and drawing documentation.
14

MOST NA D1 (LIETAVSKÁ LÚČKA - VIŠŇOVÉ) NAD ÚDOLÍM v km 4.313 / BRIDGE ON D1 (LIETAVSKÁ LÚČKA - VIŠŇOVÉ) OVER VALLEY AT km 4.313

Hudyma, Nazar Unknown Date (has links)
The subject of this Master's thesis is the design of a road bridge on the D1 in the section Lietavská Lúčka - Višňové in the Žilina Region, Žilina District, Slovak Republic. The bridge is used to cross the valley in KM 4,313 and the road in KM 4,410. Three variants of bridging were proposed, but further in the work an assessment is made on one of the variants. The total length of the superstructure is 354.00 m, the theoretical total span of the structure is 352.00 m. The bridge has 4 spans and is constructed by free cantilever method .The locations of the supports were limited by unsuitable geological conditions at the construction site (active shear area in Quaternary sediments), especially in span No. 3 (span lenght 104.00 m) and span No. 4 (span lenght 75.00 m). The monolithic part of the bridge structure will be concreted by free cantilever method with the largest length of the cantilever 52.00 m. The outermost parts of fields No. 1 and No. 4 will be cast-in-place using fixed scaffolding.
15

Návrh silničního mostu v Brně / Design of the road bridge in Brno

Kutálek, Jiří Unknown Date (has links)
The subject of the diploma thesis is a design of a highway bridge across the Svratka river in Brno. Among three options, the arch bridge with a trapezoidal bridge deck from prestressed concrete was chosen. The load effect is calculated with the assistance of Scia Engineer software. The design and the assessment of the structure are made for the ultimate limit state and serviceability limit state. Static assessment is done by hand calculation according to CSN EN 1992-2. The thesis includes drawings and visualizations of the bridge structure.
16

Comparative performance of ductile and damage protected bridge piers subjected to bi-directional earthquake attack

Mashiko, Naoto January 2006 (has links)
Incremental Dynamic Analysis (IDA) procedures are advanced and then applied to a quantitative risk assessment for bridge structures. This is achieved by combining IDA with site-dependent hazard-recurrence relations and damage outcomes. The IDA procedure is also developed as a way to select a critical earthquake motion record for a one-off destructive experiment. Three prototype bridge substructures are designed according to the loading and detailing requirements of New Zealand, Japan and Caltrans codes. From these designs 30 percent reduced scale specimens are constructed as part of an experimental investigation. The Pseudodynamic test is then to control on three specimens using the identified critical earthquake records. The results are presented in a probabilistic riskbased format. The differences in the seismic performance of the three different countries' design codes are examined. Each of these current seismic design codes strive for ductile behaviour of bridge substructures. Seismic response is expected to be resulting damage on structures, which may threaten post-earthquake serviceability. To overcome this major performance shortcoming, the seismic behaviour under bi-directional lateral loading is investigated for a bridge pier designed and constructed in accordance with Damage Avoidance principles. Due to the presence of steel armoured rocking interface at the base, it is demonstrated that damage can be avoided, but due to the lack of hysteresis it is necessary to add some supplemental damping. Experimental results of the armoured rocking pier under bi-directional loading are compared with a companion ductile design specimen.
17

Předpjatý dálniční most / Prestressed highway bridge

Blaha, Martin January 2022 (has links)
The diploma thesis deals with the design of a continuous prestressed bridge structure transferring the D56 motorway on the Frýdek-Místek bypass. The bridge bridges the local watercourse of the river Olešná, Příborská street and road II / 473. Three studies were proposed, from which a variant of a two-beam continuous prestressed monolithic slab was selected and elaborated. The static model and calculation of its internal forces took place in the program SCIA Engineer 20.0. The calculation is performed according to valid standards, limit states, which also includes the effects of construction. The work also contains detailed drawing documentation.
18

Development of a Slab-on-Girder Wood-concrete Composite Highway Bridge

Lehan, Andrew Robert 23 July 2012 (has links)
This thesis examines the development of a superstructure for a slab-on-girder wood-concrete composite highway bridge. Wood-concrete composite bridges have existed since the 1930's. Historically, they have been limited to spans of less than 10 m. Renewed research interest over the past two decades has shown great potential for longer span capabilities. Through composite action and suitable detailing, improvements in strength, stiffness, and durability can be achieved versus conventional wood bridges. The bridge makes use of a slender ultra-high performance fibre-reinforced concrete (UHPFRC) deck made partially-composite in longitudinal bending with glued-laminated wood girders. Longitudinal external unbonded post-tensioning is utilized to increase span capabilities. Prefabrication using double-T modules minimizes the need for cast-in-place concrete on-site. Durability is realized through the highly impermeable deck slab that protects the girders from moisture. Results show that the system can span up to 30 m while achieving span-to-depth ratios equivalent or better than competing slab-on-girder bridges.
19

Development of a Slab-on-Girder Wood-concrete Composite Highway Bridge

Lehan, Andrew Robert 23 July 2012 (has links)
This thesis examines the development of a superstructure for a slab-on-girder wood-concrete composite highway bridge. Wood-concrete composite bridges have existed since the 1930's. Historically, they have been limited to spans of less than 10 m. Renewed research interest over the past two decades has shown great potential for longer span capabilities. Through composite action and suitable detailing, improvements in strength, stiffness, and durability can be achieved versus conventional wood bridges. The bridge makes use of a slender ultra-high performance fibre-reinforced concrete (UHPFRC) deck made partially-composite in longitudinal bending with glued-laminated wood girders. Longitudinal external unbonded post-tensioning is utilized to increase span capabilities. Prefabrication using double-T modules minimizes the need for cast-in-place concrete on-site. Durability is realized through the highly impermeable deck slab that protects the girders from moisture. Results show that the system can span up to 30 m while achieving span-to-depth ratios equivalent or better than competing slab-on-girder bridges.
20

Simplified design method for energy dissipating devices in retrofitting of seismically isolated bridges / Méthode de conception simplifiée des amortisseurs pour la réhabilitation des ponts avec isolation sismique de la base

Golzan, Seyyed Behnam January 2016 (has links)
Abstract: Highway bridges have great values in a country because in case of any natural disaster they may serve as lines to save people’s lives. Being vulnerable under significant seismic loads, different methods can be considered to design resistant highway bridges and rehabilitate the existing ones. In this study, base isolation has been considered as one efficient method in this regards which in some cases reduces significantly the seismic load effects on the structure. By reducing the ductility demand on the structure without a notable increase of strength, the structure is designed to remain elastic under seismic loads. The problem associated with the isolated bridges, especially with elastomeric bearings, can be their excessive displacements under service and seismic loads. This can defy the purpose of using elastomeric bearings for small to medium span typical bridges where expansion joints and clearances may result in significant increase of initial and maintenance cost. Thus, supplementing the structure with dampers with some stiffness can serve as a solution which in turn, however, may increase the structure base shear. The main objective of this thesis is to provide a simplified method for the evaluation of optimal parameters for dampers in isolated bridges. Firstly, performing a parametric study, some directions are given for the use of simple isolation devices such as elastomeric bearings to rehabilitate existing bridges with high importance. Parameters like geometry of the bridge, code provisions and the type of soil on which the structure is constructed have been introduced to a typical two span bridge. It is concluded that the stiffness of the substructure, soil type and special provisions in the code can determine the employment of base isolation for retrofitting of bridges. Secondly, based on the elastic response coefficient of isolated bridges, a simplified design method of dampers for seismically isolated regular highway bridges has been presented in this study. By setting objectives for reduction of displacement and base shear variation, the required stiffness and damping of a hysteretic damper can be determined. By modelling a typical two span bridge, numerical analyses have followed to verify the effectiveness of the method. The method has been used to identify equivalent linear parameters and subsequently, nonlinear parameters of hysteretic damper for various designated scenarios of displacement and base shear requirements. Comparison of the results of the nonlinear numerical model without damper and with damper has shown that the method is sufficiently accurate. Finally, an innovative and simple hysteretic steel damper was designed. Five specimens were fabricated from two steel grades and were tested accompanying a real scale elastomeric isolator in the structural laboratory of the Université de Sherbrooke. The test procedure was to characterize the specimens by cyclic displacement controlled tests and subsequently to test them by real-time dynamic substructuring (RTDS) method. The test results were then used to establish a numerical model of the system which went through nonlinear time history analyses under several earthquakes. The outcome of the experimental and numerical showed an acceptable conformity with the simplified method. / Résumé: Les ponts routiers ont une grande valeur dans un pays parce qu’en cas de catastrophe naturelle, ils peuvent servir comme des lignes pour sauver des vies. Étant vulnérable sous des charges sismiques importantes, on peut considérer différentes méthodes pour concevoir des ponts routiers résistants et également pour réhabiliter des ponts existants. Dans cette étude, l'isolation de la base a été considérée comme une méthode efficace qui peut réduire significativement les effets des charges sismiques sur la structure. En réduisant la demande en ductilité sur la structure sans une augmentation notable de force, la structure est conçue pour rester élastique sous des charges sismiques. Le problème associé aux ponts isolés, particulièrement avec des appuis en élastomère, peut être leurs déplacements excessifs sous les charges de service et de séisme. Ceci peut défier l’objectif d'utiliser des appuis en élastomère pour les ponts typiques de petite portée où les joints de dilatation et les dégagements peuvent aboutir à une augmentation significative des frais d'exploitation et de maintenance. Ainsi, supplémenter la structure avec des amortisseurs d’une certaine rigidité peut servir de solution, ce qui peut cependant augmenter l’effort tranchant transmis à la sous-structure. Cette étude a pour but de fournir une méthode simplifiée afin d’évaluer les paramètres optimaux des amortisseurs dans les ponts isolés. Dans cette thèse, premièrement, basé sur une étude paramétrique, quelques directions sont données pour l'utilisation de dispositifs d'isolation simples, dont les appuis en élastomère, afin de réhabiliter des ponts existant avec une haute importance. Les paramètres comme la géométrie du pont, les clauses des normes et le type de sol sur lequel la structure est construite ont été appliqués sur un pont typique de deux portées. Il est conclu que les paramètres mentionnés peuvent déterminer l'emploi d'isolement de la base des ponts routiers. À la deuxième phase, basé sur le coefficient de réponse élastique des ponts isolés, une méthode de conception simplifiée d’amortisseur pour des ponts routiers réguliers isolés à la base a été présentée dans cette étude. En sélectionnant des objectifs pour la réduction du déplacement et la variation de l’effort tranchant, la rigidité et l'amortissement exigés d'un amortisseur hystérétique peuvent être déterminés. L’étude s’est poursuivie par une modélisation numérique d’un pont à deux portées pour vérifier l'efficacité de la méthode. Pour un modèle numérique d'un pont isolé typique, la méthode a été utilisée pour identifier des paramètres linéaires équivalents pour un certain déplacement et effort tranchant désigné. Par la suite, assumant un amortisseur de type hystérétique, les paramètres non linéaires de l’amortisseur ont été calculés et utilisés. La comparaison des résultats du modèle numérique sans amortisseur et avec l'amortisseur a démontré que la méthode proposée est suffisamment précise. Par la suite, un nouvel amortisseur hystérétique simple en acier a été conçu. Cinq spécimens ont été fabriqués de deux différents grades d’acier et ont été testés en combinaison avec un isolateur à l’échelle réelle dans le laboratoire de structures de l'Université de Sherbrooke. La procédure comprenait la caractérisation des spécimens par des tests cycliques en contrôle de déplacement et par la suite la réalisation d’essais par la méthode de sous-structuration dynamique en temps réel. Les résultats des essais ont été utilisés pour établir un modèle numérique du système qui a subi des analyses temporelles non linéaires sous plusieurs séismes. Le résultat des essais expérimentaux et numériques montrent une conformité acceptable avec la méthode simplifiée.

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