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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.
21

Zimní stadion v Olomouci / Winter Stadium in Olomouc

Tomčíková, Lucie January 2020 (has links)
The content of the bachelor thesis is static verification and the desing of two options of a roofing of the winter stadium in Olomouc. The object has a rectangular plan of dimension 68 x 100 m, the minimum clearance is given by requirements of the operation of winter sports. Steel construction is made of steel strength class S355. The calculations are made according to valid norms ČSN EN.
22

Rozhledna Vršek nad Zlínem / Lookout tower Vršek nad Zlínem

Hanáčík, Jan January 2015 (has links)
This thesis deals with the design and assessment of the load-bearing structure of the lookout tower. The tower is 37.45 m high with the layout in the shape of a regular octagon. The object is located within the city of Zlín. The project is provisionally drawn in two variants. Hand-static calculation, drawings and engineering report is processed only for one variant. The variants differ in the structure of staircase. The thesis is drawn up pursuant to the standards of ČSN EN.
23

Wind-induced dynamic response of a 22-storey timber building : Options for structural design of the Hallonbergen project

Tjernberg, Frida January 2015 (has links)
Folkhem is a Swedish company exclusively building timber residential buildings in the Stockholm area. The company is currently in the planning stages of what would be the world’s tallest timber building, a 22-storey timber residential buiding in Hallonbergen, Sundbyberg. In this master thesis, this proposed building has been analyzed with regards to its wind-induced dynamic response. The work includes studies of stabilization of tall structures, case studies of existing buildings and developed systems for tall timber construction and analyzed options for structural design of the Hallonbergen project. Eleven different structural systems have been investigated with regards to their displacement at the top and their peak acceleration when subject to wind loading. The peak acceleration has been calculated using both Eurocode and ISO 4354. The values have been assessed against ISO 6897 and ISO 10137. The results indicate that it is possible to construct the Hallonbergen project without risk of unacceptable dynamic response, using any of the following options; The Martinson’s system with 259 mm CLT plates The Kauffmann system The structural system presented in “The Case for Tall Wood Buildings” The structural system presented in “The Timber Tower Research Project”
24

Wind Loads on Bridges : Analysis of a three span bridge based on theoretical methods and Eurocode 1

Mohammadi, M. Sajad, Mukherjee, Rishiraj January 2013 (has links)
The limitations lying behind the applications of EN-1991-1-4, Eurocode1, actions on structures-general actions-wind load-part 1-4, lead the structural designers to a great confusion. This may be due to the fact that EC1 only provides the guidance for bridges whose fundamental modes of vibration have a constant sign (e.g. simply supported structures) or a simple linear sign (e.g. cantilever structures) and these modes are the governing modes of vibration of the structure. EC1 analyzes only the along-wind response of the structure and does not deal with the cross wind response. The simplified methods that are recommended in this code can be used to analyze structures with simple geometrical configurations. In this report, the analytical methods which are used to describe the fluctuating wind behavior and predict the relative static and dynamic response of the structure are studied and presented. The criteria used to judge the acceptability of the wind load and the corresponding structural responses along with the serviceability considerations are also presented. Then based on the given methods the wind forces acting on a continuous bridge whose main span is larger than the 50 meters (i.e. > 50 meter requires dynamic assessment) is studied and compared with the results which could be obtained from the simplified methods recommended in the EC1.
25

[pt] EFEITO DE AMORTECEDORES NO COMPORTAMENTO DINÂMICO DE EDIFÍCIOS ALTOS SOB CARGAS DE VENTO / [en] EFFECT OF DAMPERS ON THE DYNAMIC BEHAVIOUR OF TALL BUILDINGS UNDER WIND LOADS

MARINA POLONIA RIOS 12 February 2016 (has links)
[pt] O aumento da altura dos edifícios, aliado ao surgimento de materiais mais resistentes, faz com que as estruturas sejam cada vez mais esbeltas. Com isso, a ação do vento se torna um importante fator a ser considerado nesses projetos. A sua característica dinâmica provoca efeitos de vibração nas estruturas que devem ser analisados, em especial em relação ao conforto do usuário, afetado por deslocamentos e acelerações elevadas. Este estudo aborda a utilização de amortecedores fluidos como forma de reduzir a resposta dinâmica das estruturas submetidas a cargas de vento. A carga de vento consiste em um evento aleatório, devendo ser analisada estatisticamente. Desta forma, foi adotado o Método dos Ventos Sintéticos para definir o carregamento de vento aplicado à estrutura. Os amortecedores empregados na estrutura são fluidos, altamente viscosos, portanto seu comportamento pode ser considerado linear. A avaliação do comportamento da estrutura foi realizada pelo programa computacional Robot Structural Analysis. Foi feita uma análise estática afim de realizar o pré-dimensionamento da estrutura. Em seguida, fez-se uma análise dinâmica para a estrutura submetida ao carregamento de vento, com o objetivo de se analisar a influência dos amortecedores. Foram definidos cinco modelos estruturais, com diferentes configurações de amortecedores, de forma a encontrar a sua melhor distribuição na estrutura para reduzir a resposta a níveis aceitáveis de conforto para os usuários. / [en] With the increase in building height and the development of more resistant materials, structures are becoming more flexible. This has made the consideration of wind loads an important factor to be considered in their projects. The dynamic characteristic of these loads causes important vibration effects in these structures due to their low vibration frequencies, which must be considered in design, especially regarding the users comfort, affected by high displacements and acceleration. This study analyses the use of fluid dampers in order to reduce the dynamic response of the structure under wind loading. The wind load is a random phenomenon, and must be studied statistically. In the present work the Synthetic Wind Method has been adopted in order to generate the variation of the wind load in time. The dampers applied to the structure are fluid dampers, highly viscous, so its behavior can be considered linear. The computer software Robot Structural Analysis is used to study the structural behavior. An analysis considering the wind as an equivalent static load is adopted for the preliminary design. Then, a dynamic analysis is conducted, considering the structure under a time varying wind loading, to investigate the effect of the fluid dampers on the response. Five models are investigated, with different configurations for the dampers, in order to define the best configuration and obtain acceptable levels of displacements and acceleration.
26

Beräkningsmall för vindlast enligt Eurokoder samt jämförelsestudie av  vindlastberäkningsmetoder / Calculation model for wind load according to Eurocodes and a comparative study of calculation methods for wind load

Wesslund, Lovisa January 2012 (has links)
Detta examensarbete har genomförts i samarbete med byggteknikavdelning på Ramböll Sverige AB, i Norrköping/Linköping. På företaget finns ett behov av att förenkla arbetet med vindlastberäkningar för hallbyggnader enligt Eurokoden. Idag använder företaget en förenklad metod som överdimensionerar. För att kunna göra en mer exakt beräkning helt enligt Eurokoden och effektivisera arbetet har det i detta examensarbete skapats en beräkningsmall för detta ändamål. Beräkningsmallen har tagits fram i programmet Microsoft Excel. För att också kunna se konsekvenserna av att jobba med en förenklad metod, har det utförts en jämförelsestudie mellan två befintliga projekt på företaget. Resultatet av jämförelsestudien visar på vad som är anledningen till skillnaden mellan det förenklade sättet, metod 1 och det mer exakta, metod 2. Rapporten innehåller en studie kring de faktorer som används vid beräkning av vindlast. Detta har gjorts för att kunna se vilken av faktorerna som bidrar till störst skillnad i resultat mellan de båda metoderna. Som grund till allt detta, innehåller rapporten också en teoretiskt bakgrund till hur vindlast ska dimensioneras enligt Eurokoden. Detta utgör första delen av rapporten. / This study has been performed in a collaboration with the company Ramböll Sweden AB in Norrköping/Linköping. At the company there is a need to simplify calculations concerning the wind load on industrial buildings according to the Eurocode. Today the company uses a simplify method which result in an over-dimension. To make a more exact method in accordance to the Eurocode and increase the efficiency at the work, it has in this study created a calculation model for this purpose. The calculation model has been created in the program Microsoft Excel. To be able to see the consequences to work with a simplified method, it has been done a comparison study between two current project at the company. The results of the comparison study show the reason to the difference between the simplified method, method 1 and the more exact method, method 2. The report containing  a study of the factors that uses in the calculations. This has been done to see which of the factors that contributes to the largest difference in result between the both methods. As the basis for all this, the report also contains a theoretical background about how the wind load should be dimensioned according to the Eurocode. This is the first part of this report.
27

Strength Analysis of Deployable Hangar

Rudani, Manan Sureshbhai, Ring, Hampus January 2021 (has links)
It is of interest to investigate extended usability of Saab’s Deployable Aircraft Maintenance facility(DAM) with respect to Eurocode standards. One of the features of the deployable hangar is that it shouldcomply with the structural strength standards for permanent buildings which requires compliance withEurocodes.Eurocodes are European standards which deals with the development of building and structural design.Compliance with Eurocodes works as a proof of requirement for mechanical strength, stability andsafety of structures. The Eurocodes were created by the European Committee for Standardization withthe intent to simplify technical obstacles and enable trade within Europe and elsewhere.The thesis has resulted in the creation of a Finite Element Model (FE-Model) of the deployable hangar,for which different loading combinations have been applied. From the FE-results, trade-off curves havebeen generated that show the effect that the different loading conditions have on the differentcomponents of the hangar. This is done for the current configuration of the hangar and for differentproduct variants. The analysis includes the effects of increased load levels.From the trade-off curves it is possible to see to what extent the hangar can withstand increased load.This is being measured with a Eurocode ratio. It has been found that the Eurocode ratio is directlydependent on increase of loads i.e. increased loads give a linear increase in Eurocode ratio for most ofthe components studied. The product variants consists of different lengths of the hangar. From the studyit has been found that adding or removing sections does not have a substantial effect on the strength ofthe hangar and the Eurocode ratio mostly remains constant. In addition the most critical componentshave been found and design suggestions have been proposed to improve the strength of the hangarwithin compliance with Eurocodes.
28

Konstruktion och lastnedräkning av ställverk.

Bernhardsson, Emil January 2023 (has links)
Vid konstruktion av utomhusställverk behöver laster beräknas för dimensionering av fundament, stativ och grundbultar. Dessa beräkningar är tidskrävande och kräver god kunskap i standarder för ställverk. Utvecklandet av ett Exceldokument som beräknar krafterna som verkar på fundament, stativet och grundbultar, samt en ställverksmall med tillhörande stålritningar underlättar och försnabbar arbetet.  Beroende på vilken nätspänning ställverket är konstruerat för, förändras säkerhetsavståndet mellan apparater och till marken. Därför behövs det olika mallar för olika spänningar. Apparaterna som används blir tyngre och större vid högre spänningar därför måste stålet dimensioneras därefter. Dessa mallar är gjorda i Solidworks och består av sammanställning med alla stativ och apparater, samt en fundamentplan som alla delar är parade med för att enkelt kunna ändra utformningen av ställverket.  Standarder för mekanisk dimensionering av ställverkskonstruktion har följts för att göra ett exceldokument som beräknar dimensionerande laster på ställverkets stativ och fundament.  Genom att ange mått från ställverksritningen och teknisk information från beställaren i Exceldokumentet så beräknas böjspänning och vridskjuvspänning i stativen, normal- och skjuvspänning i bultar och hålkantstryck på fotplåten.  Exceldokumentet förväntas spara ca 12 timmar vid beräkning av spänningar i stativ och fundament. För ställverksmallen är förhoppningen att spara ca 80 timmar.  På grund av tidsbrist slutfördes endast en utav de nio påtänkta mallarna. Exceldokumentet skulle kunna vidareutvecklas till att beräkna vindlast på stativen och kortslutningskrafter men med minimal tidsbesparing. / During the construction of outdoor substation, loads need to be calculated to design the foundations, frames, and anchor bolts. These calculations are time-consuming and require a good understanding of standards for substations. The development of an Excel document that calculates the forces acting on the foundations, frames, and anchor bolts, along with a substation template and associated steel drawings, facilitates and speeds up the work. Depending on the voltage for which the substation is designed, the safety clearance between the equipment and the ground changes. Therefore, different templates are needed for different voltages. The equipment used becomes heavier and larger at higher voltages, so the steel must be dimensioned accordingly. These templates are created in Solidworks and consist of an assembly of all frames and equipment, as well as a foundation plan where all parts are paired to easily modify the design of the substation. Standards for the mechanical design of substation structures have been followed to create an Excel document that calculates the design loads on the substation frames and foundations. By entering some measurements from the substation drawings and some technical information from the client into the Excel document, the bending stress and shear stress in the frames, normal and shear stress in the bolts, and edge pressure on the base plate are calculated. The Excel document is expected to save approximately 12 hours when calculating stresses in the frames and foundations. For the substation template, the hope is to save around 80 hours. Due to time constraints, only one out of the planned nine templates was completed. The Excel document could be further developed to calculate wind loads on the frames and short-circuit forces, but with minimal time savings. / <p>Betygsdatum 2023-06-07</p>
29

Optimalt antal stagade spann som krävs för att stomstabilisera en stålkonstruktion : Jämförelse av olika modeller för att hitta den optimala lösningen

Al matar, Leen, Taleb, Mohamad, Abdalnour, Geolle January 2023 (has links)
Purpose: The horizontal stabilization of a building is of great importance in the design of its structural system. Insufficient counteraction of horizontal loads can lead to problems where columns and beams deflect more than the allowable margins. One common horizontal load arises from wind hitting an exterior wall. In this study, four bracing types were analyzed using software to evaluate and compare them, taking various factors into account. The building upon which the study is based is an industrial four-story structure located in Västerås. The building is designed with hinged column bases, which require a stabilization system to maintain its stability. This study aimed to determine the optimal solution for the stabilization system by comparing multiple proposals (X, V, inverted V, and diagonal) considering all factors that significantly influence stabilization. The different proposals were compared in terms of material usage, horizontal displacement, and the number of spans required for steel bracing. Method: Hand calculations were used in this report to design various structural components such as columns, beams, and bracing, which were compared with FEM (Finite Element Method) designs. Additionally, different perspectives were considered within the relevant subject framework, including steel properties, general loads, characteristics, and descriptions of the examined models. Results: After conducting the calculations, it was found that the optimal number of spans required for bracing the industrial steel structure was 32 diagonal braces, placed in the outermost bays on all sides of the building at each floor. This proposal resulted in reduced material usage with a secure horizontal displacement, ensuring stability and durability of the building. Conclusions: In conclusion, this report provides a deep understanding of the importance of stability in buildings, especially when it comes to the safety of occupants and the structural integrity of the building. Proposal 1 has likely met the requirements based on all the calculations and analyzed models that have been conducted, and therefore, diagonal bracing has been chosen as the optimized solution.
30

Avaliação em túnel de vento do comportamento da camada limite atmosférica em terrenos complexos

Mattuella, Jussara Maria Leite January 2012 (has links)
A estrutura do vento varia de acordo com as características do terreno e com a rugosidade da superfície terrestre, desacelerando proporcionalmente sua intensidade de acordo com a proximidade do solo, o que determina a constituição da camada limite atmosférica (C.L.A.). As características do escoamento sobre e no entorno de características topográficas obtusas tais como morros são de grande interesse em muitas aplicações, especialmente aquelas ligadas à engenharia de vento. Esta pesquisa foca a investigação da C.L.A. sobre terrenos complexos, analisando a estrutura do escoamento turbulento, a separação e a recomposição do mesmo. Para tanto, dois métodos são empregados e comparados na presente investigação para identificar a influência da orografia complexa sobre o escoamento do vento: padrões ou códigos de carga de vento e análises experimentais em túnel de vento. Nove modelos experimentais de morros isolados, sendo quatro simétricos bidimensionais, quatro simétricos tridimensionais e um assimétrico, todos com a consideração de dois tipos de terreno, categoria I – plano e categorias III-IV – medianamente rugosas são analisados. A partir de uma simulação experimental da camada limite em túnel de vento, é possível parametrizar os efeitos do vento sobre terrenos complexos (MILLER, 1995). A definição de variáveis, tais como: o perfil de velocidade do vento, a intensidade de turbulência, os efeitos topográficos na velocidade do vento constituem-se em elementos fundamentais para cálculos estruturais de edificações situadas no entorno. Foram desenvolvidas simulações experimentais no túnel de vento de camada limite Prof. Joaquim Blessmann, da Universidade Federal do Rio Grande do Sul. Na superfície do modelo assimétrico, na radial principal do mesmo, foram localizados nove perfis de medição, contendo cada um, vinte alturas de investigação. Os demais modelos tiveram como foco de análise o cume dos mesmos, também com perfis definidos nas mesmas alturas. As medições da velocidade do vento e da intensidade da turbulência foram procedidas por um sistema de anemometria de fio quente. Os dados obtidos em túnel de vento foram confrontados com expressões empíricas calculadas para os mesmos pontos segundo cinco códigos ou padrões de carga de vento, pontuando também as correlações entre os mesmos e entre estes com a norma brasileira NBR 6123 (1988). Os modelos, códigos ou padrões analisados foram: Jackson e Hunt (1975) e Davenport, Surry e Lemelin (1988), models e as normas a seguir nominadas:Norma Brasileira: cargas de vento em Edificações - NBR 6123 (1988); European Standard:Eurocode1: Basis of Design and Actions on Structures, CEN TC 250: 2002; Australian/New Zealand Standard: Minimum Design Loads on Structures, AS/NZS 1170.2: 2002; Architectural Institute of Japan AIJ: 2004; American Society of Civil Engineering Standard, ASCE 7-95 (ASCE 7-95), Minimum Design Loads for Buildings and Other Structures;National Building Code of Canada, 2005, (NRCC 2005). Além do estudo comparativo acerca da resposta estimada pelos códigos nominados, esta pesquisa constitui-se em um banco de dados de medições em pontos localizados nos morros nominados, em túnel de vento. O comparativo entre os padrões mostra a inexistência de uma harmonização entre os mesmos para a consideração dos parâmetros a serem empregues para o cálculo de cargas de vento. Estas diferenças na definição dos parâmetros básicos para o carregamento de vento em estruturas determinam grandes dificuldades na unificação de formatos recomendados na previsão das cargas de vento. Comparativamente aos dados experimentais, os padrões, em geral, mostram-se conservadores para os dois tipos de morros analisados, simétrico e assimétrico, para os dois tipos de terreno, tanto considerando-se análises em 2D ou 3D. / The structure of the wind varies with the characteristics of the terrain and roughness land surface, slowing its intensity proportionally according to the surrounding terrain, which determines the onset of boundary layer (ABL). The characteristics of the flow over and around topographic features such as hills are of great interest in many applications, especially those related to wind engineering. From an experimental simulation of the boundary layer wind tunnel, it is possible to parameterize the effects of wind over complex terrain (MILLER, 1995). The definition of variables, such as the profile of wind speed, the turbulence intensity, the topographic effects on wind speed are key elements in structural calculations for buildings situated around the area. This research focuses on the investigation of the ABL complex terrain conditions, analyzing the structure of turbulent flow and characterization of separation and reattachment of the flow. Experimental simulations were developed in the wind tunnel of the atmospheric boundary layer Prof. Joaquim Blessmann, Federal University of Rio Grande do Sul in nine models of hills, four symmetrical two-dimensional, four- symmetrical threedimensional and one asymmetrical, all considering two types of terrain, category I - plan and Category III-IV- moderately rough. The surface of the asymmetric model was measured in nine profiles ploted on the main radial of the hill, with twenty heights each, and the other models were examined at top of the hill. The measurements were performed with a system of hot wire anemometry to measure the wind velocity and intensity of turbulence. The identification of the data obtained in the wind tunnel were confronted with empirical expressions for the same points, in order to establish the correlations between patterns and among these with NBR 6123 (1988). Two models and five codes of wind loads are analyzed: Jackson and Hunt (1975) and e Davenport, Surry e Lemelin (1988) Models and Brazilian Association of Technical Standards: Wind Load on Buildings, NBR 6123 (1988); European Standard: Eurocode1: Basis of Design and Actions on Structures, CEN TC 250: 2002; Australian/New Zealand Standard: Minimum Design Loads on Structures, AS/NZS 1170.2: 2002; Architectural Institute of Japan AIJ: 2004; American Society of Civil Engineering Standard, ASCE 7-95 (ASCE 7-95), Minimum Design Loads for Buildings and Other Structures; National Building Code of Canada, 2005, (NRCC 2005) codes. This study focuses not only the comparison of the response estimated by international codes nominees, but also a data bank of wind tunnel data to validate this tool based on empirical expressions. The comparison of the patterns shows a lack of consideration for international harmonization of the parameters to be employed for the calculations of wind loads. These differences in defining the basic parameters for the wind loading on structures determines difficulties to unify the formats recommended in the prediction of wind loads. Compared to the experimental data, the patterns will generally show up conservative for both types of mounts analyzed, symmetrical and asymmetrical, for both types of terrain, both considering 2D or 3D.

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