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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

Ligações em estruturas de aço / Steel structure connections

Vitor Cesar Valenciani 29 October 1997 (has links)
Este trabalho consiste numa revisão bibliográfica sobre ligações em estruturas de aço. Inicialmente são abordados os dispositivos de ligação, enfatizando os tipos e as características estruturais dos conectores, os processos de soldagem mais empregados nas estruturas de aço e suas implicações. A seguir são apresentados os aspectos mais importantes sobre o comportamento estrutural de parafusos e soldas e a avaliação da resistência com base na norma brasileira NBR 8800 e nas principais normas estrangeiras aplicáveis. Finalmente, são apresentados e discutidos os modelos teóricos clássicos usualmente empregados para a avaliação de solicitações em ligações parafusadas e soldadas. / This work gives a reference review on steel structure connections. First, connection designs are discussed, emphasizing the types of fasteners, their characteristics, the most common employed welding processes for steel structures and the technical implications. It is also presented the most important aspects regarding the structural behaviour of bolts, welds and the strength evaluation based on the Brazilian code NBR 8800, as well as on the main known foreign codes. Finally the classical theoretical analysis often adopted for the evaluation of welded and bolted connections are presented and discussed.
102

Interstitial diffusion from the weld metal into the high temperature heat affected zone in 11-12% chromium steel welded joints

Meyer, Arnold Matthys 29 September 2008 (has links)
Please read the abstract in the section, 00front, of this document / Dissertation (MEng)--University of Pretoria, 2008. / Materials Science and Metallurgical Engineering / unrestricted
103

Análise numérica de segunda ordem de pórticos planos de estruturas de aço / Numerical second order analysis for steel plane frames

Leitão, Giles Bortolon, 1981- 24 August 2018 (has links)
Orientador: João Alberto Venegas Requena / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-24T08:57:31Z (GMT). No. of bitstreams: 1 Leitao_GilesBortolon_M.pdf: 2415614 bytes, checksum: c72f6dbca268737bcbe1fb87e8b8a236 (MD5) Previous issue date: 2014 / Resumo: Este trabalho trata da análise numérica de segunda ordem de pórticos planos de estruturas de aço. A norma brasileira ABNT NBR8800:2008 recomenda o uso de análise de segunda ordem para qualquer estrutura sempre que os deslocamentos afetarem de forma significativa os seus esforços internos, e apresenta um processo analítico simplificado para obter a análise de segunda ordem de pórticos planos de estruturas de aço. Como se trata de um processo analítico e aproximado, além de trabalhoso, propõe-se neste trabalho um processo numérico de análise de segunda ordem, utilizando o processo das funções de rigidez com a hipótese dos pequenos deslocamentos, com a finalidade de determinar os esforços para verificação de perfis de pórticos planos, de forma rápida, precisa e automática. Utilizaram-se as simplificações da norma brasileira para a consideração das imperfeições iniciais geométricas e de material. Desenvolveu-se também, dentro do programa, a verificação de perfis laminados de aço para análise de primeira e segunda ordem. Exemplos de pórticos são apresentados para validação dos resultados dos esforços obtidos numericamente pelo programa de computador desenvolvido e para compará-los com os obtidos pelo método de cálculo analítico simplificado indicado pela referida norma / Abstract: This work approaches numerical second order analysis for steel plane frames. The Brazilian standard ABNT NBR8800:2008 specifies use of second order analysis for any structure where the displacements significantly affect their internal forces and presents a simplified analytical process to obtain second order analysis for steel plane frames. As it is a laborious approximated analytical process, it is proposed in this work a numerical second order analysis method, using rigidity functions process, with hypothesis of small displacements, in order to determine the forces to design plane frames profiles, by a quickly, accurately and automatically way. It was used simplifications of the Brazilian standard for consideration of initial geometric and material imperfections. Also, it was developed inside the software, verification of hot rolled steel profiles for first and second order analysis. Frame examples are presented to validate the results of efforts obtained numerically by the developed software and to compare them with those obtained by the simplified analytical method presented in the standard. / Mestrado / Estruturas / Mestre em Engenharia Civil
104

Ocelová konstrukce výrobní haly / The Steel Structure of a Factory Building

Ivánek, Robert January 2013 (has links)
Item of Master´s thesis is to design, review and compare two variants of steel structures production hall with overhead crane with load capacity 25t. One variant is frame construction and second one is construction with trusses. Layout dimensions is 45m x 60m and the height of the ridge is 10m. Stability is provided by wall and roof bracings. Building is sheathed. Structures is situated in Frýdek - Místek.
105

Metodika posuzování konstrukcí pozemních staveb vyrobených z patinující oceli pro soudní znalce / Methodology for Judicial Experts on Assessment of Structures produced of Weathering steel

Pošvářová, Miloslava January 2008 (has links)
Content of Doctoral thesis is a methodology for juridical experts on the assessment of structures manufactured of weathering steel, with special attention to evaluation of the protective corrosion layer.
106

Assessment of Feasibility of Proposed Bolted Connections for Tubular Structures

Tausch, John Henry 15 November 1977 (has links)
The search for new and additional sources of energy -- from sun, wind, waves, and ocean currents -- is necessitating the development of structures in the open environment of the oceans as well as on land. The advantages of round or tubular members for use in such structures are shown; and to avoid the uncertainties of welded joints, two bolted connections are proposed and their feasibility explored.
107

Probabilistic Approaches to Optimization of Steel Structures Considering Uncertainty / 不確定性を考慮した鋼構造物の確率的最適化手法

DO, KIM BACH 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(工学) / 甲第24575号 / 工博第5081号 / 新制||工||1973(附属図書館) / 京都大学大学院工学研究科建築学専攻 / (主査)教授 大崎 純, 教授 池田 芳樹, 准教授 藤田 皓平 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
108

Using Incremental Dynamic Analysis to Visualize the Effects of Viscous Fluid Dampers on Steel Moment Frame Drift

Kruep, Stephanie Jean 11 September 2007 (has links)
This thesis presents the details of a study regarding both the use of linear viscous fluid dampers in controlling the interstory drift in steel moment frames, and the use of incremental dynamic analysis as a method of visualizing the behavior of these moment frames when subjected to seismic load effects. Models of three story and nine story steel moment frames were designed to meet typical strength requirements for office buildings in Seattle, Washington. These models were intentionally designed to violate seismic interstory drift restrictions to test the ability of the linear viscous fluid dampers to reduce these drifts to the point of code compliance. Dampers were included in one bay of every story in each model. These devices were used to produce total structural damping ratios of 5%, 10%, 20%, and 30% of critical. Undamped, traditional stiffness controlled models of both three stories and nine stories were also created for comparison purposes. Incremental dynamic analysis was used to subject these models to ten ground motions, each scaled to twenty incremental levels. Two new computer applications were written to facilitate this process. The results of these analyses were studied to determine if the linear viscous fluid dampers were able to cause compliance with codified drift limits. Also, incremental dynamic analysis plots were created to examine the effects of the dampers on structural behavior as damping increased from inherent to 30% of critical. It was found that including linear viscous fluid dampers in steel moment frame design can satisfactorily control interstory drift, and incremental dynamic analysis is a beneficial tool in visualizing dynamic structural behavior. / Master of Science
109

High-Resolution Modeling of Steel Structures

Surampudi, Bala Anjani Vasudha 07 November 2017 (has links)
No description available.
110

Patch loading resistance of welded I-beams : with respect to misaligned web stiffeners

Boutzas, John-Alexander, Zeka, Dafina January 2016 (has links)
When a concentrated load is introduced perpendicular to the flanges of a steel beam, this condition is referred to as Patch loading (Gozzi, 2007). This occurrence is common in many steel structures, for example at supports or during launching of bridges. Because of the usual slenderness of I-beams and other plated structures, these are sometimes reinforced with stiffeners in order to avoid buckling. Modifications, such as adding stiffeners to a beam, are done to make greater plastic deformations possible before buckling can occur; thereby increasing the resistance against failure. Transverse stiffeners are added in areas where the beam is exposed to concentrated loads (Lagerqvist, 1994). The descriptions of calculating patch loading in the Eurocode are presented for cases of double stiffeners, with the load applied in between two stiffeners with same distance to each of them, or when there is one single stiffener that is acting in line with the load. In the Eurocode there are also descriptions on how to calculate on the resistance against patch loading when there are no stiffeners added. However, the Eurocode lacks descriptions for cases when the stiffeners are misaligned. The purpose of this paper is the evaluation of the impact from transverse stiffeners to the resistance of welded I-beams, when the stiffeners are misaligned and where the length of the beam varies. Because of the complexity of such of problems it is almost impossible to find theoretical solutions (Lagerqvist & Johansson, 1996). Therefore, in this study as well as in almost all studies that aim to predict the ultimate resistances of steel beams subjected to patch loading, the results are gained empirically. The tests herein were done by FE-modeling and the results from the physical experiments done in Lagerkvist’s doctoral thesis were used for validation of the model, as conducting experiments ourselves was not economically possible. 6 The study was made in two steps. In the first step FE-models were produced under the same circumstances as the results obtained by Lagerqvist (1994). Those analyses were not part of the aim of the study; the intention for making the initial analyses was to strengthen the reliability of the results. From there, the final analyses were made with the aim in investigating the influence of stiffeners on the resistance, when these are misaligned. In this step, observations were also made with regards to the impact of the bending moment of the beam on its resistance. The initial analyses, which were made for validation of the modeling, had a satisfying correspondence to the physical experiments; hence the final analyses are assumed valid of acceptance. From observations of the results in the final analyses it is noticed that adding stiffeners is a highly preferred way of increasing the resistance for slender beams. For full utilization it is however important to have the stiffeners optimally placed, because a small deviation from this position gives an unwanted decrease in resistance.

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