No / This paper summarises recent experimental research on structural steel I-section beam/column connections for fire safety, based on a programme of research on robustness of different types of steel beam/column connections, carried out in collaboration between the Universities of Sheffield and Manchester. In this research project, two series of connection tests were conducted, one on isolated connections under different combinations of axial load, shear and moment at different elevated temperatures, and one on steel beam-to-column assemblies in fire, in which the resulting connection forces were varied during the fire exposure. This paper summarises the results and the main findings of these tests, focusing on connection failure modes, tying resistance, the rotation capacity of different types of connection and their potential influences on fire resistance of the connected members. The principal objective of this paper is to discuss the implications of this research project on integrating fire resistance into the design of steel-framed structures, firstly to highlight connection characteristics which contribute most to overall robustness, and to suggest how connection detailing might change to enable connections to possess such desirable characteristics.

Orientador: João Alberto Venegas Requena / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-25T16:56:00Z (GMT). No. of bitstreams: 1 Fidalgo_AugustoMadrigali_M.pdf: 8655271 bytes, checksum: 8636b5b90c043f307e3e2dde1a8696ff (MD5) Previous issue date: 2014 / Resumo: Este trabalho consiste no estudo teórico e numérico de uma ligação flange, solicitada inicialmente por força axial de tração e, em um segundo momento, por uma força excêntrica de tração. Essa ligação é usada em estruturas metálicas tubulares para emenda de barras e, especificamente nesse projeto, em perfis tubulares circulares. É uma ligação parafusada e soldada, com flanges circulares nas duas extremidades das barras, soldados de forma continua e sem furo no meio da placa, também chamada de "Blank Flange", conectando as barras. A grande parte das bibliografias e normas atuais preveem para esse tipo de ligação o dimensionamento apenas para solicitação de força axial de tração, dentre as estudadas, apenas uma prevê o dimensionamento com solicitação excêntrica. Assim, nesse trabalho foi feita uma modelagem numérica, usando o software Ansys, para estudar o comportamento dessa ligação frente à solicitação axial de tração, verificando o mecanismo do efeito "Prying", ou efeito alavanca, e sua influência na resistência da peça. Usando esse modelo, foi verificada a validade das formulações para a tração, o mecanismo de funcionamento da ligação e a possibilidade de otimização do cálculo, que hoje é feito com fórmulas empíricas, das quais não se conhece os dados de ensaios. Por fim, uma vez calibrado o modelo numérico para tração e verificado o cálculo proposto, ele foi ajustado para simular o flange submetido à flexo-tração, e com isso seu comportamento foi estudado e proposta uma formulação para esse dimensionamento / Abstract: The research is about a theoretical and numerical analysis of flange connection, initially subject to axial tensile load, and then to an eccentric tensile load. This kind of joint is used in hollow steel structures, and specifically in this work, using circular hollow section. Flange is a bolted and welded connection, which both tubes are welded on continuous circular plates, without holes, called Blank Flange, and this plates are bolted together. Most bibliography and codes, used in this research, have only the axial tensile design for flange, just one of them have the flexure tensile one. Because of that, this research proposed a numerical model in Ansys, to study how this joint behave subject to axial tensile load, checking prying effect, or cantilever effect, and its influence in joint resistance. Using this model, the axial tensile design was validated numerically, joints behavior was analyzed and the possibility to optimized the actual design, which is based on empirical equations. Therefore, once the numerical model for axial tensile load and it¿s design was calibrated, this was changed to simulate eccentric tensile load, to study its behavior and propose a design / Mestrado / Estruturas / Mestre em Engenharia Civil

No / This paper describes the experimental results of ten fire tests on medium-scale restrained steel sub-frames to investigate the relative behaviour and robustness of different types of steel joint in steel framed structures in fire. The ten fire tests were designed to investigate the effects of two column sizes (simulating two different levels of axial restraint to the connected beam) and five different types of joint, including fin plate, web cleat, flush endplate, flexible endplate and extended endplate connections. Each test frame, in the form of “rugby goalpost” consisting of one beam and two columns, was connected through two identical beam to column joints. All the steelwork was unprotected except for the top flange of the beam which was protected to simulate the effect of a concrete slab in reducing the beam top flange temperature. The column ends were restrained to examine the effects of axial restraint on the beam and the joints. This paper presents the observations of structural fire behaviour, including joint failure modes and beam limiting temperatures, the development of deflections at beam middle span and axial forces in the joints at elevated temperatures. The main conclusions are: (1) failure (fracture) was observed only in joints when the beam was in catenary action and a variety of joint failure modes were observed which provides valuable data in understanding joint behaviour; (2) the medium-scale steel beams were able to undergo very large deflections View the MathML source without failure; (3) the specimens with stronger connections such as extended endplate reached higher than their limiting temperatures, defined as the beam bottom flange temperature at middle span at which the axial load in the beam returned to zero. But the difference in beam limiting temperatures using different types of joint is small, less than 50 °C; also the column size had little effect (less than 30 °C) on the beam limiting temperature; (4) the beams connected to the larger column experienced less deflections, but higher axial force due to the higher axial restraint to the beam, which led to fracture of the joint components in these tests; in contrast, the lighter columns visibly deformed and formed plastic hinges at the joints, but there was little evidence of connection fracture in the test frames using the light columns; (5) the web cleat connection appears to have the best performance.

Timber moment resisting connections have gained considerable interest in structural design due to the numerous advantages offered by timber as a lightweight, renewable, sustainable, and aesthetically pleasing material. This research focuses on investigating the feasibility and potential benefits of hybrid timber-steel moment connections in enhancing the seismic performance and ductility of timber structures. The objective is to evaluate the response modification factors of the hybrid timbersteel moment-resisting frames to see if this type of moment connection has the ability to perform like steel moment-resisting frames in lateral loadings. The process by which the studied frames were designed was focused on preventing damage to timber elements by inducing inelastic deformations exclusively in the steel beams, while the remaining parts of the frame retain their elasticity. Nonlinear static analysis is employed to evaluate the force modification factors and nonlinear behavior of the selected structures. In this study, a total of 18 frames with different span lengths, numbers of stories, and seismicity levels were analyzed to comprehensively investigate their seismic performance. The frames were designed to represent a range of practical configurations commonly found in timber structures. The span lengths of 4, 6, and 8 meters were considered. The number of stories were 2, 4, and 6, and the frames were located in Montreal, QC, and Vancouver, BC, which are known for having varying seismic conditions. By considering a diverse set of frames, this study tried to provide a comprehensive understanding of the behavior and performance of different timber frame structures under seismic loading, taking into account the effects of span length, number of stories, and regional seismic conditions. The results of the analysis offer a preliminary understanding of the seismic performance and potential advantages of steel-timber moment connection frames. However, it should be noted that further research is needed to conduct full-scale experimental tests to validate the proposed connections and gather more accurate data. The findings from this study have the potential to contribute to the development of new seismic provisions for moment connection timber frame systems, advancing the field of timber structural design and offering potential design schemes that increase ductility and performance in timber moment resisting connections.

Syfte: Syftet med arbetet är att förbättra dimensioneringsprocessen för knutpunkter i stålstrukturer. Förslag har getts på en förbättrad dimensionsprocess baserad på de BIMrelaterade datorprogrammen SBI Steel Connections och FEM-design. Syftet har brutits ner till följande frågeställningar:  Hur går konsultföretag till väga idag för att beräkna knutpunkter vid stålkonstruktioner?  Hur kan den vanligaste dimensioneringsprocessen för knutpunkter förbättras?  Vilka fördelar blir det vid en sammankoppling av de BIM-relaterade datorprogrammen SBI Steel Connections och FEM-design? Metod: Arbetet grundar sig i en fallstudie och ett flertal metoder användes för att samla in data. Dessa är semistrukturerade intervjuer, litteratursökning, dokumentanalys och beräkningar. Resultat: Genom arbetet framgår det hur dimensioneringsprocessen ser ut för knutpunkter i stål. Resultatet är att processen varierar beroende på företag. Vissa delar i processen kan utföras på olika sätt men grundprincipen är densamma för de flesta företagen som har intervjuats. Vid dimensionering av knutpunkter som kan ske både för hand och med hjälp av ett datorprogram kan det uppstå felslag vid inmatning eller felskrivningar. Denna del av processen kan förbättras med hjälp av en ökad användning av egengjorda mallar. Det sker ett utvecklingsarbete under våren 2015 där målet är att skapa en sammankoppling mellan SBI Steel Connections och FEM-design. Genom denna sammankoppling reduceras några av de fel som anses tillhöra den mänskliga faktorn. Konsekvenser: Undersökningen har medfört en förståelse med både fördelar och nackdelar för olika sätt att dimensionera knutpunkter i stål. En del företag stävar efter en större utveckling, medan andra anser sig jobba bäst på det sätt som de alltid har gjort. Det framgår att den mänskliga faktorn är något som påverkar dimensioneringsprocessen märkbart och dessa fel behöver reduceras. De rekommendationer som framgår i arbetet är att företag ska se över processen och de förnyelsemöjligheter som finns i branschen. Det rekommenderas även en större användning av de datorprogram som används vid dimensioneringsprocessen. Begränsningar: Avgränsningar gjordes utifrån de kunskaper som erhållits i utbildningen för att studien inte skulle bli alltför omfattande. Däremot har ny kunskap bidragit till ett större ämnesdjup som utbildningen inte berört. Studien orienterades kring knutpunkter av stål och en av de vanligaste knutpunkterna studerades. Stålkvalitet och dimensioner på pelare och balk valdes utifrån knutpunktsexemplet i SBI:s handbok publikation 186 (PT3). Rapporten behandlar enbart beräkningsprogrammen SBI Steel Connections och FEM-Design. Detta medförde endast avgränsningar på material, val av knutpunkt, pelar- och balkprofiler samt laster.

No description available.

En pelarfot är en stål-till-betongknutpunkt som består av en fotplåt med insvetsad stålpelare och grundskruvar som gjuts ner i betonggrundkonstruktionen. Pelarfoten används till att överföra lasten från bärande pelare ner till grunden och grundskruvarna hjälper till att ta upp skjuvkrafter samt dragkrafter som uppstår av böjmoment. Vid dimensionering av pelarfötter finns principer och råd för beräkning att hämta från Eurokoderna. Dock kan det ta tid att hitta alla anvisningar som finns spridda mellan olika Eurokoder. I praktiken är det effektivt att använda något av de designprogram som är specialiserade förknutpunktermed automatisk beräkningsfunktion. I denna rapport studeras beräkningsprinciper enligt Eurokoderna som underlag förförståelse av dimensionering av en pelarfot. Sedan används designprogram för att dimensionera pelarfoten. Målet är att ta reda på vilket eller vilka program som är lämpligast för dimensionering av pelarfötter. Programmen som används är Peikko Designer, IDEA StatiCa och FEM-Design Steel Joint där alla har sina egna beräkningsrutiner för att uppfylla Eurokoderna. Utvärderingen gjordes endast för pelarfotstypen PF3 med samma lastkombinationer i tre fallstudier. För grundskruvar användes standardskruvar från Peikkos sortiment vid förankringen. Resultatet visade sig att programmen är lämpligast för sitt användningssyfte. Peikko Designer är lämpligast för beräkning av sina egna grundskruvar. IDEA StatiCa är lämpligast för dimensionering av pelarfötter i allmänhet med större noggrannhet med hjälp av FEM. FEM-Design Steel Joint är däremot inte längre lämpligt vid användning på grund av en gammal standard. / A column base is a steel-to-concrete connection that consists of a base plate welded to a steel column and anchor bolts casted into the concrete foundation. The column base is used to transfer loads from the load-bearing column to the foundation and the anchor bolts help to absorb shear forces as well as tensile forces that arise from bending moments. When designing a column base, there are calculation principles and advice to be taken fromtheEurocodes. However, it can take time to find all the instructions indifferent to Eurocodes. In practice, it is efficient to use design programs that specialize in steel connections with automatic calculation functions. In this report, calculation principles according to the Eurocodes are studied as a basis for understanding the design of a column base. Then design programs are used to verify the column base. The goal is to find out which program or programs are most suitable for practical use.  The programs used are Peikko Designer, IDEA StatiCa and FEM-Design Steel Joint, where all of which have their own calculation routines for complying with the Eurocodes. The evaluation was made only considering the column base type PF3with the same load combinations in three case studies. For anchor bolts, Peikko’s standard anchor bolts are used for anchoring. The result showed that the programs are most suitable for their intended use. Peikko Designer is most suitable for calculating its own anchor bolts. IDEA StatiCa is most suitable for design of column bases in general with greater accuracy using FEM. However, the FEM-Design Steel Joint is no longer suitable for use due to implementation of an old standard.

No description available.

Thesis (MEng)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: The South African National Standard for the structural use of cold-formed steel (SANS 10162-2) provides capacity prediction models for screwed connections. Screwed connections are designed against shear failure of the screw(s), section tear-out, net section failure and tilt-andbearing failure. Previous studies (Rogers & Hancock, 1997) showed that the capacity is typically determined by the tilt-and-bearing type failure mode. The aim of this document is to report on the reliability of single screwed connections in cold-formed steel against this critical failure mode. Predicted nominal capacities depend on the ultimate tensile strength of the steel, the thickness of the connected plates and the diameter of the screw. Design capacities are obtained by multiplying the nominal capacities by a capacity reduction factor of 0.5, according to SANS 10162-2. Reliability is assessed by means of FORM analyses, taking uncertainty in the prediction model and variability of input parameters into account. Laboratory testing of 222 single screwed connections allowed to statistically describe the model factor, i.e. the ratio of actual tested- over unbiased predicted capacity. For each connection, the steel strength, plate thickness and screw diameter were measured, with the measured values used to predict capacity. This implies that the model factor accounts for uncertainty in the prediction model and experimental setup, while the variability of input parameters is separately accounted for through appropriate statistical modelling. Variability in the input parameters was described using appropriate statistical distributions from expert literature (Holicky, 2009:199; JCSS, 2000). For steel strength, the mean value and standard deviation were obtained from tensile tests, while mean values and standard deviations of the plate thickness and screw diameter were obtained from the above mentioned measurements. The experimental work and numerical analysis resulted in a model factor with a mean just exceeding unity and a small standard deviation. This suggests that the design code under consideration is able to accurately predict the nominal capacity of screwed connections. The FORM analysis resulted in computed reliability indexes significantly higher than the corresponding target values which suggest conservative and reliable design formulations. Die eksperimentele werk en numeriese analise het gelei tot 'n model faktor met 'n gemiddeld hoër as een en 'n klein standaardafwyking. Dit dui daarop aan dat die ontwerp-kode onder oorweging in staat is om die nominale kapasitiet van skroef verbindings akkuraat te voorspel. Die betroubaarheid analise het gelei tot betroubaarheidsindekse aansienlik hoër as die ooreenstemmende teiken waardes wat daarop dui dat die ontwerp formulerings betroubaar en hoogs konserwatief is. / AFRIKAANSE OPSOMMING: Die Suid-Afrikaanse Nasionale Standaard vir die strukturele gebruik van koud gevormde staal (SANS 10162-2) bied voorspellingsmodelle vir die kapasitiet van skroef verbindings. Skroef verbindings word ontwerp teen skroef faling, staal profiel faling, die uitskeer van skroewe en ook faling weens skroef kanteling. Vorige studies (Rogers & Hancock, 1997) het getoon dat die kapasiteit gewoonlik bepaal word deur die skroef-kantel falingsmodus. Die doel van hierdie navorsing is om verslag te doen oor die betroubaarheid van tipiese enkel skroef verbindings in koud gevormde staal strukture teen hierdie kritiese falingsmodus. Voorspelde nominale kapasiteite hang af van die treksterkte van die staal, die dikte van die verbonde profiele en die diameter van die skroef. Volgens die SANS 10162-2 word die ontwerp kapasiteit verkry deur die nominale kapasiteit met 'n kapasiteitsverminderingsfaktor van 0.5 te vermenigvuldig. Betroubaarheid word ontleed deur middel van ʼn eerste orde betroubaarheidsmetode analise, met die in ag neming van onsekerheid in die voorspellingsmodel en wisselvalligheid van die parameters. Laboratoriumtoetse van 222 enkel skroef verbindings het ʼn statistiese beskrywing van die model faktor toegelaat. Die model faktor is bereken as die verhouding tussen die getoetste kapasitiet en die voorspelde kapasitiet. Die staal sterkte, profiel dikte en skroef diameter is gemeet vir elke verbinding met die gemete waardes wat gebruik is om die kapasiteit te voorspel. Dit beteken dat die model faktor slegs onsekerhede in die voorspellingsmodel en van die eksperimentele opstelling in ag neem, terwyl die wisselvalligheid van die parameters afsonderlik in ag geneem word deur toepaslike statistiese modellering. Variasie in die parameters is beskryf met gepaste statistiese verdelings voorgestel deur verskeie literatuur (Holicky, 2009:199; JCSS, 2000). Aangaande die staal sterkte, is die gemiddelde waardes en standaardafwykings verkry deur standaard trek toetse terwyl die gemiddelde waardes en standaardafwykings van die plaat dikte en skroef diameter verkry is deur die bogenoemde metings.

It is vital that Turkey keep abreast of developments in the world and build up its technology to become a developed country. Steel construction is one of these areas. In this context, the main purpose of this study was to define, analyze and evaluate the general characteristics of structural steel and steel construction with the purpose of throwing new light on its advantages and disadvantages. Within this framework, a literature survey was conducted on structural steel components and structures / and on steel construction in Turkey. Additionally, a case study was carried out on a steel office building in Ankara. In this, the T&uuml / rkiye Esnaf ve Sanatkar Kredi Kefalet Kooperatifleri Merkez Birligi (TESKOMB) Building was investigated in terms of the design and production criteria for steel structures and to determine problems faced during these processes. As a result of this study, the existing condition of the construction sector and the means to improve use of structural steel in Turkey were discussed more realistically.